Closed Car Loading Guide - Transportation Technology Center

Transcription

Closed Car Loading Guide - Transportation Technology Center
Closed Car Loading Guide
Part 1
(formerly Pamphlet No. 14)
Minimum Loading Standards for
Freight in General Purpose
Boxcars
Approved 1/6/14 by the
Damage Prevention and
Freight Claim Committee
Copyright © 2014 by the Association of American Railroads (AAR)
425 Third Street SW
Washington, DC 20024
All rights reserved, including the right to reproduce this book in any form. It is the AAR’s intention that this
publication be used to promote the objectives of the AAR and its members for the safe, efficient, and uniform
interchange of rail equipment in North America. To this end, only excerpts of a rule or specification may be
reproduced by the purchaser for their own use in promoting this objective. No portion of this publication may be
displayed or otherwise made available to multiple users through any electronic distribution media including but not
limited to a local area network or the Internet. No portion may be sold or used for advertisement or gain by any entity
other than the AAR and its authorized distributor(s) without written permission from the AAR.
Minimum Loading Standards for
FREIGHT
IN GENERAL PURPOSE BOXCARS
(Supersedes Pamphlet No. 14, Published December 1984;
Cancels G.I.S. Nos. 583, 701, 709, and 715
Issued: January 2014
Published by
Transportation Technology Center, Inc.
55500 DOT Road
Pueblo, CO 81001
(Printed in U.S.A.)
© 2014
(This Page Left Blank Intentionally)
TABLE OF CONTENTS
1.0
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1
1.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1–1
1.2 Reference Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1–1
1.3 Rail Transportation Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1–2
2.0
Selection and Preparation of Car. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–1
2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2–1
2.2 Bulkhead Doors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2–2
3.0
General Loading Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–1
3.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3–1
3.2 Concentrated Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3–1
3.3 Clearance at Side Bearing—Loaded Cars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3–2
3.4 Maximum Load Weight. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3–2
3.5 Distribution of Weight Lengthwise in Cars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3–2
3.6 Distribution of Weight Crosswise in Cars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3–3
3.7 Center of Gravity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3–4
4.0
Load Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–1
5.0
Unitizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1
5.1 On Wooden Pallets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–1
5.2 Slip-Sheeted Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–3
5.3 Clamped Units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–3
5.4 Stretch Wrap and Shrink Net Characteristics and Application. . . . . . . . . . . . . . . . . . . . . . .5–3
6.0
Blocking and Bracing Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1
6.1 Steel Strapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6–1
6.2 Nonmetallic Strapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6–4
6.3 Web Strap Assemblies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6–9
6.4 Cargo Nets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6–10
6.5 Lumber. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6–11
6.6 Nails and Nailing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6–13
6.7 Pneumatic Dunnage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6–14
6.8 Friction Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6–16
7.0
Gates, Fillers, Separators, and Dividers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–1
7.1 Gates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7–1
7.2 Fillers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7–2
7.3 Separators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7–8
7.4 Dividers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7–9
7.5 Risers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7–10
8.0
Load Securement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–1
8.1 Floor Blocking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8–1
8.2 Anchored Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8–2
8.3 Incomplete Layer Bracing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8–3
9.0
Doorway Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–1
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
TOC–i
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TOC–ii
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
LIST OF FIGURES
Figure 2.1
Figure 3.1
Figure 3.2
Figure 4.1
Figure 4.2
Figure 4.3
Figure 4.4
Figure 4.5
Figure 5.1
Figure 5.2
Figure 5.3
Figure 5.4
Figure 6.1
Figure 6.2
Figure 6.3
Figure 6.4
Figure 6.5
Figure 6.6
Figure 6.7
Figure 6.8
Figure 6.9
Figure 6.10
Figure 6.11
Figure 6.12
Figure 6.13
Figure 6.14
Figure 6.15
Figure 6.16
Figure 7.1
Figure 7.2
Figure 7.3
Figure 7.4
Figure 7.5
Figure 7.6
Figure 7.7
Figure 7.8
Figure 7.9
Figure 7.10
Figure 7.11
Figure 7.12
Figure 7.13
Figure 7.14
Figure 7.15
Figure 7.16
Figure 7.17
Figure 7.18
Figure 7.19
Bulkhead doors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–2
Concentrated floor loading card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–2
Distribution of weight full length of car . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–2
Placing lifts in cars with staggered doors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–1
Placing lifts in cars with staggered doors using pneumatic dunnage . . . . . . . . . . . . 4–2
Key sack method of loading bags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–2
Brick wall method of loading bags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–3
Use of lengthwise fillers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–3
Using lengthwise filler to fill pallet underhang . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1
Examples of maintaining vertical alignment of unitized containers . . . . . . . . . . . . 5–2
Method of preparing a two-way pallet for placement crosswise in the doorway . . 5–2
Taping slip sheet lips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–3
Crimp-type joint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1
Notch-type joint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1
Triple die-cut sealless joint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–3
Sealless joint with reverse die-cut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–3
Threading a wire buckle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–6
Threading a cordstrap CB buckle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–7
Threading a ladder-type buckle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–7
Threading a Tapex FCT-12 buckle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–8
Attaching Type 1A, Grade 3, 4, or 5 strap to side-wall anchors . . . . . . . . . . . . . . . 6–8
Web strap assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–9
Sample web defects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–9
Attaching cargo nets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–10
Cargo net attachment —top view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–11
Selecting wood blocking and bracing material . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–11
Pneumatic dunnage installed vertically . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–15
Pneumatic dunnage installed horizontally . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–15
Divisional gate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–1
Center gate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–1
Methods of using fillers to square bowed end walls . . . . . . . . . . . . . . . . . . . . . . . . 7–2
Lengthwise fillers in resilient lading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–2
Lengthwise fillers in rigid lading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–3
Reinforced lengthwise filler panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–4
Lengthwise void fillers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–4
Contour buffer pads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–5
Use of crosswise fillers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–6
Examples of fillers used to fill crosswise space . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–7
Lateral void fillers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–7
Unitized double layer bag or bale loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–8
Contour polyethylene foam pads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–8
Plywood divider sheets between different lading types . . . . . . . . . . . . . . . . . . . . . . 7–9
Fiberboard divider sheets between similar lading types . . . . . . . . . . . . . . . . . . . . . 7–9
Unitized double-layer pallet loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–9
Riser strips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–10
Riser pad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–10
Risers used to break strata line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–12
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars Figures–iii
Figure 8.1
Figure 8.2
Figure 8.3
Figure 8.4
Figure 8.5
Figure 8.6
Figure 9.1
Figure 9.2
Figure 9.3
Figure 9.4
Figure 9.5
Figure 9.6
Guide rails used for lateral bracing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Draping a car for an anchored load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Anchored load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Anchored load using web strap assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Incomplete layer bracing—rigid loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Incomplete layer bracing—paper roll . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wood doorway protection for a single-layer load . . . . . . . . . . . . . . . . . . . . . . . . . .
Steel strap doorway protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conventional and belt-type strap applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conventional key band doorway protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure-8 key band doorway protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Doorway protection for sliding or plug-door cars loaded with plywood . . . . . . . . .
8–1
8–2
8–2
8–3
8–3
8–4
9–1
9–1
9–2
9–3
9–3
9–4
Figures–iv Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
LIST OF TABLES
Table 3.1
Table 3.2
Table 3.3
Table 3.4
Table 6.1
Table 6.2
Table 6.3
Table 6.4
Table 6.5
Table 6.6
Table 6.7
Table 6.8
Table 6.9
Table 6.10
Table 6.11
Table 6.12
Table 6.13
Table 6.14
Table 6.15
Table 7.1
Table 9.1
Boxcar end wall strength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–1
Length of load versus percentage of stenciled load limit . . . . . . . . . . . . . . . . . . . . . 3–3
Load weight as percentage of load limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–3
Load weight versus spring deflection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–4
Steel securement straps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1
AAR approved steel band manufacturers and suppliers and assigned AAR ID. . . . 6–2
AAR approved high-strength Type I regular-duty package bands . . . . . . . . . . . . . . 6–2
Approved steel strapping sealless tool manufacturers (triple die-cut sealless joint) 6–3
Approved sealless tool for 1 14 in. steel strapping bands
(sealless joint with reverse die-cut). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–3
Approved Type IV polyester strapping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–4
Approved Type 1A bonded polyester strapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–5
Approved Type 1A polyester strapping Grades 6 and 7. . . . . . . . . . . . . . . . . . . . . . 6–6
Standard thicknesses for yard lumber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–12
Species of wood most commonly used for bracing . . . . . . . . . . . . . . . . . . . . . . . . 6–12
Substitution guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–12
Common nails, power driven nails, and power driven staples . . . . . . . . . . . . . . . . 6–13
Lateral resistance of nails when driven through 2-in.-thick floor blocking
and into boxcar floor (lb) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–13
Substitution of power-driven nails or staples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–13
Performance level application guide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–14
Minimum riser strip and pad sizes for rolls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–10
Substitution rate for nonmetallic strap as doorway protection . . . . . . . . . . . . . . . . . 9–2
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
Tables–v
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Tables–vi Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
INTRODUCTION
1.0 INTRODUCTION
1.1 Overview
1.1.1 The purpose of this guide is to relate basic good car loading procedures that have been
developed through laboratory and field testing, engineering studies, and accumulated experience
in rail transportation. Many commodities or packaging types, such as paper, prepared food,
plywood, and intermediate bulk containers, are governed in greater detail in individual closed car
loading guides. Commodity-specific guides will normally take precedence over these general
guidelines. See the back cover for a complete listing of the Association of American Railroads’
(AAR) closed car loading guides.
1.1.2 Compliance with the “Minimum Loading Standards” contained herein will ensure
conformance with Circular No. 42-K rules and provide adequate protection for lading from sources
of damage in the normal railroad environment.
1.1.3 The general rules contained in Circular No. 42-K or supplements thereto issued by the AAR
are formulated for the purpose of providing safe methods of loading boxcars and must be observed.
1.1.4 The loading rules and/or practices apply to shipments transported in the USA, Canada, and
Mexico.
1.1.5 The loading methods in individual closed car loading publications issued by AAR’s Damage
Prevention and Loading Services are minimum standards that have been evaluated and approved
by the AAR Damage Prevention and Freight Claim Committee. The minimum standards offer
practical guidelines on the subjects covered. Because these are minimum standards, it may be
necessary to supplement the methods in some instances.
1.1.6 Securement standards in AAR closed car loading publications are intended for safe transit
of the railcar from origin to destination and for the prevention of lading and equipment damage.
The standards do not address unloading practices.
1.1.7 Loading and bracing methods not currently approved may receive consideration for
approval and publication under the Damage Prevention and Loading Services General
Information Bulletin, No. 2, “Procedures Governing Evaluation and Acceptance of New Closed Car
Loading and Bracing Methods and Materials.” Submit requests to Director, Damage Prevention
and Loading Services, Association of American Railroads, Transportation Technology Center, Inc.,
55500 DOT Road, Pueblo, CO 81001.
1.1.8 CAUTION: Car rocking motion caused by lift equipment entering and/or exiting the railcar
may cause unsupported packages or articles with a high center of gravity to fall to the floor.
Minimize access to the car. Exercise caution when inside a partially loaded car. Lift operators
should stay on lift equipment, whenever possible, while inside a partially loaded car.
1.2 Reference Documents
1.2.1 Circular No. 42-K (or supplements thereto)
“General Rules Covering Loading of Carload Shipments of Commodities in Closed Cars”—These
requirements must be observed in all closed car loading activities to ensure safe transit of the
railcar from origin to destination, thereby eliminating hazard to railroad operation.
1.2.2 Circular No. 43-E (or supplements thereto)
“Rules Governing the Loading, Blocking, and Bracing of Freight in Closed Trailers and Containers
for TOFC/COFC Service”—This publication contains the requirements covering loads in trailers or
containers.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
1–1
INTRODUCTION
1.3 Rail Transportation Environment
1.3.1 There are inherent characteristics of the rail environment that must be understood to
recognize the need for many of the requirements identified in this publication.
1.3.2 Forces encountered within the rail vehicle are induced by shock and/or vibration. In most
instances, the force is a complex result of both shock and vibration. Force input due to shock is
mainly a result of impacts during switching and train slack action (run-in and run-out during
train movement). Force input due to vibration is a result of the movement of the railcar’s wheels on
the rails. This vibration force can act either in a vertical or lateral plane. These forces are due to
the movement of the car wheels on the rails, the truck geometry, rail joints, rail elasticity,
nonuniformities of the rail and wheels, and overall track condition. When all these factors are
acting on a rail vehicle, the resultant force is very complex.
1.3.3 The lading in a rail vehicle can also generate forces; for instance, in canned commodities,
the metal cans can act as springs. For multilayer loads in the rail vehicle, any vertical force input
in the bottom layers can be greatly amplified as it travels to the top layers. This is the
transmissibility factor due to the harmonics of a particular stack or column of containers.
1.3.4 Uncontrolled movement and/or displacement of the lading in a rail vehicle can cause safety
problems, equipment failure, damage, and unloading problems. The following minimum loading
standards in conjunction with proper packaging will provide safe arrivals.
1–2
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
SELECTION AND PREPARATION OF CAR
2.0 SELECTION AND PREPARATION OF CAR
2.1 Overview
2.1.1 Be careful around railroad equipment. If you are unfamiliar with the proper way to operate
equipment, check with your supervisor and obtain the proper training needed to safely do your job.
2.1.2 Railroads are responsible for supplying cars that are clean and have sound roofs, sides, and
square end walls; smooth floors; and snug-fitting doors. Any exception is cause for rejection.
Shippers are responsible for inspecting interiors of cars to see that they are suitable to carry
lading safely and damage-free.
2.1.3 Before attempting to open the doors of any railcar, check to make sure that all hardware is
intact so that the doors open safely. Check the door tracks to make sure they are equipped with
stops on the ends so that the doors do not fall off when opened.
• It is critical to check locking bars and related hardware to make sure you can safely open
plug doors.
• Make sure the doors are operating correctly before fully opening them. There is always the
possibility that material or lading may be leaning against the inside doors or is applying
pressure.
• Use extreme care when opening any type of railcar door to protect against injury.
2.1.4 Always check the car to see if water entry is possible. Make sure that the car is watertight.
Look for light leaks or evidence of new or large amounts of rust, which may indicate recent water
entry into the car. Check the car floors for any holes or rough surfaces that may result in leakage
or damage to the product.
(Note to customers: Notify appropriate carriers immediately if railcars are received with water
damage to ensure that the car is shopped and repaired before the car is used again.)
2.1.5 Inspect the cars for any protrusions or rough, broken, or bent surfaces that could result in
damage to the product. It is important that cars are clean and free from nails, brads, staples,
fragments of steel, and dunnage remnants. To prevent damage, cover projections of lining or
anchor devices with protective materials taped in place or otherwise adequately secured.
2.1.6 Check the end walls to make sure they are not bowed. If the end wall is severely bowed,
reject the car. If the end walls are bowed and you need to use the car, use materials of appropriate
size and strength to bring the end walls back to square. This will help to ensure that the load
remains tight during its journey. See Figure 7.3.
2.1.7 If the car supplied is not suitable for loading and the shipper elects to load the car rather
than reject it, it is the shipper’s responsibility to properly prepare the car.
2.1.8 Cover rough surfaces with fiberboard sheets or other suitable materials. Do not use kraft
paper.
2.1.9 In refrigerator cars, cover floor racks with at least a single thickness of corrugated
fiberboard, placing the corrugations lengthwise of the car to prevent rolling or bunching. Abut
sheets on the floor and do not overlap. Make the interior end wall adjacent to the motor
compartment flush with the end walls by adding several thicknesses of corrugated fiberboard.
2.1.10 When plug doors do not provide a flush surface with the car’s side walls, use protective
material such as corrugated fiberboard.
2.1.11 The loading methods illustrated in this guide have a proven track record of success in
specific car types. Please note the type of car for which each method is used. Failure to use the
proper loading method in the proper type of equipment will result in damage to the product and a
dissatisfied customer (i.e., if a loading method is shown for use in a cushion equipped car, use that
loading method only in cushion equipped cars).
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
2–1
SELECTION AND PREPARATION OF CAR
2.2 Bulkhead Doors
2.2.1 When cars are equipped with bulkhead doors, inspect the doors to determine if they can be
moved safely, then move the doors to approximately where they will be located under load. Engage
the locking mechanisms to make certain they are operational. Inspect for full extension all locking
pins at the top and bottom of the bulkhead doors. Locking pins must penetrate the tracks a
minimum of 12 in. Tapered locking pins must penetrate the tracks a minimum of 12 in. beyond the
taper (see Figure 2.1).
LOCKING PINS MUST PENETRATE THE FLOOR AND CEILING
LOCKING TRACKS A MINIMUM OF 1/2 IN.
MINIMUM
1/2 IN.
Figure 2.1 Bulkhead doors
2.2.2 Weight of cargo restrained by each bulkhead must not exceed one-half of the load limit
stenciled on the car sides.
2.2.3 Examine all bulkhead doors before loading. This cannot be emphasized too strongly. Before
moving a bulkhead door, inspect the overhead assembly to determine if it is in good condition so
the door can be moved safely.
2.2.4 Inspect locking handles to determine if they function properly. Inspect locking pins to make
sure they penetrate into the holes of the overhead and floor locking tracks. If locking pins do not
penetrate, DO NOT LOAD.
2.2.5 After cargo is loaded, place the door squarely (straight up and down) and snugly against the
load, and lock into place. If the face of the load is not flush, use filler material to make it flush. If
the door’s surface is not smooth, protect the product with fiberboard.
2.2.6 Inspect the locking pins to make sure they have penetrated the overhead and floor locking
tracks a minimum of 12 in.
2–2
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
GENERAL LOADING INFORMATION
3.0 GENERAL LOADING INFORMATION
3.1 Overview
3.1.1 This section reprints mandatory rules contained in AAR Circular 42-K. For the most up-todate rules, see Circular 42-K or supplements thereto.
3.1.2 Load, block, or brace commodities tightly lengthwise and crosswise to eliminate all void
spaces that are primary reasons for damage. Take up any void spaces remaining in a car. Use
blocking, fillers, and other suitable materials, and secure them in accordance with the methods
outlined in this guide and other guides listed on the back cover of this book.
3.1.3 Load and secure lading to permit unloading from either side of the railcar, except when
dimensions of individual units of freight prohibit unloading from either side of the car.
3.1.4 When loading, segregate and protect commodities that may cross contaminate.
3.1.5 The ends of boxcars are designed to withstand a horizontal force induced by the lading
without exceeding the yield strength of the material (see Table 3.1).
Table 3.1 Boxcar end wall strength
Percentage of Total Force
Uniformly Distributed
Nominal Capacity of
Car (ton)
Total Force on End
Wall (lb)
Top Half
Bottom Half
50
100,000
35–45
65–55
70
220,000
35–45
65–55
100 (263,000 lb)
260,000
35–45
65–55
100 (286,000 lb)
284,000
35–45
65–55
3.2 Concentrated Loads
3.2.1 Boxcars used for loading and transporting heavy concentrated weight (e.g., metal) must be
inspected by the originating carrier (either before they are placed for loading or at loading point)
for suitability to safely carry such loads to their destination.
3.2.2 When ordering boxcars for loading concentrated weights of heavy commodities, shippers are
responsible for notifying serving carriers of the heavy-weight conditions and if the cars were not
inspected by the originating carrier for these conditions.
3.2.3 Observe the concentrated load restrictions stenciled on the side of the car adjacent to the
doors; e.g., 50K or 75K, which indicate the maximum front axle load for lift trucks entering the
railcar.
3.2.4 Boxcars furnished for loading and transporting heavy concentrated weight (e.g., tin plate,
copper anodes, lead ingots, cathodes, zinc slabs, spelters, and all other high-density commodities)
must meet the following requirements:
3.2.4.1 Cars must be stenciled 25K, 50K, 70K, or 80K adjacent to door opening, indicating floor
loading capacity.
3.2.4.2 Wood floors must be 2¼ in. thick in sound condition supported by at least three metal
floor stringers on each side of the center sill the full length of the car.
3.2.4.3 If equipped with sliding sill underframe, wood floors must be 2¼ in. thick in sound
condition supported by at least two metal floor stringers on each side of the center sill the full
length of the car.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
3–1
GENERAL LOADING INFORMATION
3.2.4.4 If equipped with steel floors or special-type wooden flooring the full length of the car, the
overall strength of the floor must be not less than that of a floor with three stringers as specified
above.
3.2.4.5 Boxcar must be checked by the shipper to see that the floors and supporting structure are
in good condition. If the shipper has any doubts concerning the condition of the car, the serving
railroad should be contacted.
3.2.4.6 Shippers have the responsibility of attaching a concentrated floor loading card, shown in
Figure 3.1, to the routing or placard board on each side of the boxcar loaded with metals with
densities exceeding 400 lb/ft3 and/or 800 lb/ft2 floor-bearing area.
Figure 3.1 Concentrated floor loading card
3.2.4.7 Loads occupying less than the total floor space that could cause unbalanced distribution
within the car must be secured to prevent movement.
3.3 Clearance at Side Bearing—Loaded Cars
For cars not equipped with constant-contact-type side bearings (zero clearance normal), clearance
must be maintained at side bearings to permit free curvature of trucks.
3.4 Maximum Load Weight
3.4.1 Load weight in the car must not exceed the load limit stenciled on the car.
3.4.2 Load weight on one truck must not exceed one-half of the load limit stenciled on the car.
3.5 Distribution of Weight Lengthwise in Cars
3.5.1 For all boxcars, except for those with staggered double-doors built before 1966, the
percentages of stenciled load limits shown in Figure 3.2 must not be exceeded for loads located
between truck centers, measured to full length of the car, unless car owners have otherwise noted
in the Official Railway Equipment Register.
Figure 3.2 Distribution of weight full length of car
3–2
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
GENERAL LOADING INFORMATION
3.5.2 For staggered double-door boxcars built before 1966, the percentages listed in Figure 3.2
are as follows:
Table 3.2 Length of load versus percentage of stenciled load limit
Inside Length of Car
Length of Load
40 ft
50 ft
10 ft to 20 ft
40%
35%
20 ft 1 in. to 24 ft
45%
40%
24 ft 1 in. to truck centers
75%
75%
Truck centers to full length of car
100%
100%
If the maximum load is 40% of stenciled load limit, the provisions in paragraphs 3.4.1 and 3.4.2
would not apply.
3.5.3 Weight of material loaded in either end between truck centers and end of car must not
exceed 15% of stenciled load limit for boxcars built before January 1, 1966, and 25% for cars built
after January 1, 1966.
3.5.4 When crosswise bearing pieces are used, the distance between the outside bearing pieces
(center-to-center) must exceed the minimum distances specified in paragraphs 3.5.1 and 3.5.2 for
that percentage of the stenciled load limit being loaded and be in sufficient number to ensure
uniform distribution of lading on the car floor.
3.5.5 Bearing pieces lengthwise of the car, extending beyond the lading, may be used to spread
weight distribution over a greater area. In such cases, “Length of Bearing Pieces” is substituted for
“Length of Load” in paragraphs 3.5.1 and 3.5.2. Bearing pieces must be of suitable strength in
relation to percentages stated and must be continuous and in sufficient number to ensure uniform
distribution of lading on the car floor.
3.5.6 When the length of load is less than the distance between truck centers, and the load is not
located in the center of the car, the center of load weight must not be nearer to either truck center
than that shown in Table 3.3:
Table 3.3 Load weight as percentage of load limit
50% of load limit or less Any place between truck centers
60%
One-sixth distance between truck centers
66.6%
One-fourth distance between truck centers
75%
One-third distance between truck centers
87%
Three-sevenths distance between truck centers
90%
Nine-twentieths distance between truck centers
3.6 Distribution of Weight Crosswise in Cars
3.6.1 The load must be located so that the weight along both sides of the car is approximately
equal for the entire length of the load.
3.6.2 When the load is such that it cannot be placed to obtain equal distribution of weight
crosswise of the car, use properly secured and suitable ballast to equalize the weight.
3.6.3 In boxcars, lading must be secured to prevent tipping or moving toward the sides of the car
where the vacant space across the car exceeds the following:
• An aggregate of 18 in. crosswise of car
• Vacant crosswise space of less than 18 in. as may be specified in guides covering methods
for loading, bracing, and blocking carload shipments of individual commodities
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
3–3
GENERAL LOADING INFORMATION
3.7 Center of Gravity
3.7.1 Combined center of gravity of railcars and contents must not exceed 98 in. above top of rail.
In closed cars, there is no practical possibility of exceeding this center of gravity limitation, except
in cars that exceed Plate C dimensions. Railcar plate dimensions can be found in the Official
Railway Equipment Register.
3.7.2 Cars exceeding Plate C dimensions may extend to 17 ft above top of rail. Certain lading,
such as rolled paper loaded two layers high, may result in excessive combined center of gravity
dimensions. Shippers must calculate the combined center of gravity of the railcar and contents
whenever any part of the load will exceed 11 ft 8 in. (140 in.) in height above the car floor.
Shipper’s tender of billing information for such cars to the origin carrier will signify compliance
with this rule. Any questions on loading limitations in cars exceeding Plate C dimensions should
be handled with the Mechanical Department of the origin carrier.
3.7.3 Use the following formula to calculate the combined center of gravity:
A =Height of car floor above top of rail in inches
B =Empty center of gravity of railcar above top of rail in inches, obtainable
from car owner (empty center of gravity may be stenciled on the railcar)
C =Center of gravity of load above car floor in inches
D=Height of center of gravity of load above top of rail, equal to A + C
E =Lightweight of railcar in pounds
F =Weight of load in pounds
 B  E  +  D  F -
3.7.4 Combined center of gravity (CG) = ------------------------------------------E + F
3.7.5 The following table may be used as a guideline when determining A in the above formula:
Table 3.4 Load weight versus spring deflection
Weight of Load (lb) Spring Deflection (in.)
3–4
122,000–137,000
1.00
138,000–164,000
1.25
165,000–191,000
1.50
192,000–207,000
1.75
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
GENERAL LOADING INFORMATION
3.7.6 EXAMPLE: Roll Paper
Load:(a) 9 rolls (stacks) @ 13,000 lb each 151 in. wide (high)
(b) 9 rolls (stacks) @ 7,600 lb each 76 in. wide (high)
NOTE: When loads consist of multiple sections or units having different unit heights and weights,
such as (a) and (b) above, each section or unit must be taken separately when calculating the CG of the
load.
A = 44 in.
B = 58 in.
C = (a) 151 in./2 = 75.5 in.
(b) 76 in./2 = 38 in.
D = (a) 75.5 in. + 44 in. = 119.5 in.
(b) 38 in. + 44 in. = 82 in.
E = 72,800 lb
F = (a) 9 × 13,000 lb = 117,000 lb
(b) 9 × 7,600 lb = 68,400 lb
B  E  +  D  a   F  a   +  D  b   F  b  -
Combined CG = ------------------------------------------------------------------------------------------------------E + Fa + Fb
 58  72 800  +  119.5  117 000  +  82  68 400 
= ------------------------------------------------------------------------------------------------------------------------------- 72 800 + 117 000 + 68 400 
= 92.23 in. above top of rail (ATR)
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
3–5
GENERAL LOADING INFORMATION
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3–6
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
LOAD PLANNING
4.0 LOAD PLANNING
4.1 Inspect lading before loading car. Do not load damaged lading.
4.2 Stow shipping containers in the position to best utilize the constructed strength of each
shipping container.
4.3 Handle and stow all lading according to the shipper’s printed directions; e.g., “This Side Up,”
“Do Not Drop,” and “Clamp Here.”
4.4 Separate irregular lading from regular lading by blocking and bracing.
4.5 Load longest dimension of narrow-base items lengthwise of the car.
4.6 Evenly distribute the weight of loads from side-to-side and end-to-end in the car and to a
uniform height of lading insofar as lading permits. Place lighter shipping containers on top of
heavier containers. Use separating material as needed between layers. Stow like-sized shipping
containers in stacks, and use divider material between stacks of different-sized shipping
containers and shipping containers of different densities.
4.7 Plan load so that crosswise space is minimized without exceeding an aggregate of 18 in.,
unless additional appropriate bracing is used. Maintain vertical alignment to prevent crosswise
movement.
4.8 Plan loads so that a combination of end wall fillers, separators, and center bracing will
facilitate unloading lengthwise lifts from both sides of cars equipped with staggered doors.
4.9 Center bracing, as shown in Figures 4.1 and 4.2, may be either wood bracing or disposable
inflatable dunnage. When dunnage is composed of wood blocking, use both vertical and horizontal
members of sufficient strength to ensure dunnage does not collapse or become dislodged when
experiencing dynamic conditions en route.
CENTER BRACING
Figure 4.1 Placing lifts in cars with staggered doors
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
4–1
LOAD PLANNING
PNEUMATIC
DUNNAGE AND
FILLER PANELS
Figure 4.2 Placing lifts in cars with staggered doors using pneumatic dunnage
4.10 In hand-stowed shipments, use key sack or brick wall loading patterns for bag loads (see
Figures 4.3 and 4.4). In the key sack arrangement, the key bags are loaded in the lengthwise
direction of the car. Bags located on top of the key bags are in the crosswise position.
LINE CAR WALLS
WHERE NECESSARY
KEY SACKS
Figure 4.3 Key sack method of loading bags
4–2
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
LOAD PLANNING
ALTERNATE LAYER PATTERN
FOR EACH SUCCESSIVE LAYER
Figure 4.4 Brick wall method of loading bags
4.11 Stow lading in a manner to prevent contact with doorposts.
4.12 Fill all lengthwise space with lading and with lading and filler material, or appropriately
block and brace, unless a floating load method is used. See Figure 4.5.
SPACE FILLED NOT TO
EXCEED 8 IN. IN ANY
ONE LOCATION
Figure 4.5 Use of lengthwise fillers
4.13 When there is a possibility of lading falling or rolling out of the doorway or coming in contact
with sliding or plug-type side doors, openings must be protected with wood doorway protection,
steel straps, or other material of sufficient strength and number, and be adequately secured. Cars
equipped with plug-type doors loaded with cylindrical items, such as rolls of paper or drums,
require doorway protection unless specifically exempted by applicable commodity guides. See
paragraph 9.0, Doorway Protection.
4.14 Observe all restraining capacities for specially equipped cars.
4.15 Apply temporary bracing in partly loaded or unloaded cars that will be switched during the
process of loading or unloading.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
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LOAD PLANNING
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4–4
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
UNITIZING
5.0 UNITIZING
Unitizing shipping containers is an efficient means of handling, storing, loading, transporting, and
unloading, which contributes to efficient utilization of carrier equipment. The following guidelines
suggest ways to obtain the best stack stability in unit loads.
5.1 On Wooden Pallets
5.1.1 Stack individual pallet loads of shipping containers by bonded block or other interlocking
methods.
5.1.2 Ensure that pallets are of sufficient strength for the type of product handled and are in good
condition with no broken boards or protruding objects.
5.1.3 When loading, provide palletized units with unit-to-unit contact with minimum overhang of
shipping containers on pallets.
5.1.4 No pallet under-hang, lengthwise of the railcar, is permitted except when filled with
approved filler material. Figure 5.1 shows a method of filling under-hang on pallets by using
expanded corrugated honeycomb fiberboard with glued facings of single-wall corrugated
fiberboard.
SPACE FILLED NOT TO
EXCEED 8 IN.
Figure 5.1 Using lengthwise filler to fill pallet underhang
5.1.5 Filler construction: lengthwise void fillers must be of uniform strength over the face of the
void filler and capable of withstanding a load of 1,500 lb/ft2 (test full-dimension filler sheet).
5.1.6 Make the height and width dimensions of the faces of the filler material as near as possible
to the dimensions of the faces of the units they will be separating.
5.1.7 Do not reuse filler material if it has been damaged and is no longer capable of filling the
intended void, or if there is any evidence of creasing or damage to the core, which might reduce the
compression strength of the filler.
5.1.8 Do not use lengthwise void filler material as a bulkhead or in lieu of a bulkhead.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
5–1
UNITIZING
5.1.9 Maintain vertical alignment of shipping containers on wooden pallets by using fillers,
corrugated sleeves, corner protectors and strapping, stretch wrapping, shrink wrapping, spot
gluing, taping, or other methods proven by shipment. See Figure 5.2.
CORNER POSTS AND STRAPPING
(CORNER POSTS MAY BE LAMINATED
PAPER, MULTIWALL CORRUGATED, OR
OTHER SUITABLE MATERIAL)
CORRUGATED FIBERBOARD
SLEEVES
SPOT GLUING OF CONTAINERS
(DOUBLE-DASHED LINES
REPRESENT GLUE LINES)
STRETCH, SHRINK, OR NET
WRAPPING
Figure 5.2 Examples of maintaining vertical alignment of unitized containers
5.1.10 Use load-restraining devices or filler material to take up all lengthwise voids between
pallets.
5.1.11 Load as many units across the car as practical, as long as units are loaded in a straight
line lengthwise in the car. Use filler material (see Figures 7.10 and 7.11) to maintain vertical
alignment and prevent crosswise movement of lading.
5.1.12 In double-layer pallet loads, have units equal in height to ensure pallet contact both
longitudinally and laterally. If this is not the case, separate stacks of units with suitable divider
sheets (see Figures 7.14 and 7.15).
5.1.13 Load and brace lading to permit unloading from either side of railcar. Use four-way entry
pallets in doorway, if possible.
5.1.14 Use four-way entry pallets in doorway area to facilitate unloading. See Figure 5.3 for a
method of preparing two-way entry pallets for placement in doorway area of car.
NORMAL 48 IN. × 40 IN. TWO-WAY
PALLET WITH THREE RUNNERS
ADDITIONAL 2 IN. × 4 IN. PIECES
NAILED TO BOTTOM OF PALLET
Figure 5.3 Method of preparing a two-way pallet for placement crosswise in the doorway
5–2
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
UNITIZING
5.2 Slip-Sheeted Units
5.2.1 Match slip-sheet strength to the weight of the load. For lightweight cases, use corrugated
slip sheets (with corrugations running lengthwise to load), lightweight solid fiber, or plastic slip
sheets. For heavyweight cases and bagged or baled products, use heavyweight solid-fiber slip
sheets to avoid tearing the lips.
5.2.2 Use the same size stacking surface of the slip sheet as the unit load.
5.2.3 Tape or secure slip-sheet lips to prevent damaging adjacent units and to facilitate
unloading. See Figure 5.4.
Figure 5.4 Taping slip sheet lips
5.2.4 Have units provide unit-to-unit contact lengthwise in car.
5.2.5 To facilitate unloading, double sheet the doorway units so that a lip under each unit faces
each car door.
5.3 Clamped Units
5.3.1 When cars are clamp-loaded and side voids exist, apply fillers along both side walls in the
car and in the center void.
5.3.2 In the doorway area, use fiberboard divider sheets adjacent to each side of the doorway
units to facilitate unloading.
5.4 Stretch Wrap and Shrink Net Characteristics and Application
5.4.1 Stretch Wrap
• Minimum of 1 mil, low-density (0.92 g/cc) polyethylene with a stretch range of 150% to
200% or equivalent.
• Three successive layers of film applied to cube weights of 1,000 lb or less, and four
successive layers of film applied to cube weights of over 1,000 lb. Tension should not crease
products but should be sufficient to stretch film 150% to 200%.
• Stretch film must encompass all layers of each unit, including the full pallet.
5.4.2 Shrink Net
• Use woven polypropylene with a density of 1.29 oz/yd2, with four strands per inch in the
machine direction and three strands per inch in the cross direction, with a shrink range of
12% to 15%.
• Use netting to encase all layers of the product, including the full pallet.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
5–3
UNITIZING
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5–4
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
BLOCKING AND BRACING MATERIALS
6.0 BLOCKING AND BRACING MATERIALS
6.1 Steel Strapping
See Tables 6.1 through 6.3. For the latest updates to these tables, go to TTCI’s Web site at
http://www.aar.com/standards/open_top_loading_approvals.php
6.1.1 Unless otherwise specified in commodity guides, make the combined joint strength of the
number of steel straps for rigid braced loads in each longitudinal impact direction greater than or
equal to the weight of the lading being secured.
6.1.2 Use the proper combination of steel straps, seals, sealing tools, crimps, or notches to provide
the minimum joint strength for sizes listed in Table 6.1. Figures 6.1 and 6.3 show crimp- and
notch-type joints.
Table 6.1 Steel securement straps
Width and
Thickness
(in.)
Width and
Thickness
(mm)
Minimum
Breaking
Strength
(lb)
Minimum
Joint
Strength 75%
of MBS
(lb)
Minimum No. Pairs
of Notches on Joint
Surface Finish
All Types
Securement Bands
Minimum No. Pairs of
Crimps on Joint
Surface Finish
Not Waxed
Waxed
Std.
Grit
Grit
1 1/4 × .029
31.75 × .75
4,750
3,565
2
3
3
4
1 1/4 × .031
31.75 × .79
4,750
3,565
2
3
3
4
1 1/4 × .035
31.75 × .89
4,750
3,565
2
3
3
4
1 1/4 × .044
31.75 × 1.12
6,750
5,065
4
4
4
4
1 1/4 × .050
31.75 × 1.27
6,750
5,065
4
4
4
4
1 1/4 × .065
31.75 × 1.65
8,900
6,675
N/A
4
4
6
2 × .044
50.80 × 1.12
10,600
7,950
4
4
4
Std.
Grit
6
4
2 × .050
50.80 × 1.27
10,600
7,950
4
4
4
6
4
2 × .065
50.80 × 1.65
13,800
10,350
4
4
4
6
4
Note: Apply a sufficient number of seals to accommodate the proper number of pairs of notches or crimps.
Figure 6.1 Crimp-type joint
Figure 6.2 Notch-type joint
6.1.3 The number of notches or crimps shown in Table 6.1 is based on current general
recommendations of high tension strapping manufacturers on the basis that tensioning and
sealing tools are in proper operating condition. A lesser number of notches or crimps may be used
provided the shipper can demonstrate that the joint has the minimum strength shown in Table 6.1
under the column labeled “Minimum Joint Strength 75% of MBS (lb).”
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
6–1
BLOCKING AND BRACING MATERIALS
6.1.4 AAR Approved Steel Bands, Manufacturers, and Suppliers
Table 6.2 AAR approved steel band manufacturers and suppliers and assigned AAR ID
Company
11
E
ITW/Acme Packaging
6/15
11
E
ITW/Signode (Mexico)
6/15
11
E
22, 33, 47
D, I
52
I
2
Package Bands
Band Width (in.)
1 1/4
1 1/4
X
ITW/Signode
6/15
X
Samuel Strapping Systems
6/16
X X
Gerrard-Ovalstrapping
6/16
X
X X X
X
X X
X
X X X
X
d/
57
I
Maillis Strapping Systems—
USA Inc.
12/15
58
I
DuBose Strapping Inc.
6/15
56
D
LS Strapping, Inc.
8/14
48
D
Independent Metal Strap Co.
4/15
X
X
X
X X
X
2/15
X X
X
X
Hankum Co., Ltd.
X
X X
1/16
I
X X X X X X
X X
1/14
26
X X
X X X X
D, I, P Garibaldi (Chile)e/
5/16
X
X X X X X
d/
20
Hankum Co., Ltd.
1/2
X X X X X X X X X X X X X X X X X X X X X X X
D, I, P Garibaldi (Chile)e/
I
5/8
X
20
26
3/4
.065
.050
.044
.065
.050
.044
.040
.035
.031
.029
.040
.025
.020
.050
.044
.035
.031
.029
.028
.025
.023
.022
.020
.023
.020
.023
.020
Approved
Throughc/
AAR
IDa/
Marking
Methodb/
Securement Bands
Band Width (in.)
X X X
X
X
X
X
X
X
X
X X X
X
X X X X X X X X
d/
X X
X X
X
X X X X X
X
X
a/ All AAR identification numbers or marks are to be preceded with the letters “AAR.”
b/ Legend of marking methods: D = steel die imprint; E = steel embossed; I = ink print; P = paint embossed
c/ Month and year, 3-year approval per the Open Top Loading Rules Manual, Section 1, Rule 3, expires at the end of the date shown
unless approval is renewed.
d/ Meets ASTM D3953 and OTLR requirements of 1 1/4 in. × 0.044 steel banding crimp seal only.
e/ Garibaldi (Chile)—1 14 in. and 34 in. steel die imprint and ink print marking, 58 in. paint embossed only.
Note: This table corresponds with AAR the Open Top Loading Rules Manual, Section 1, Table 17.8. Current as of July 10, 2013.
Table 6.3 AAR approved high-strength Type I regular-duty package bands
Company
Strap Name
Size (in.)
Samuel Strapping Systems
Ultra Ten
1/2
× .020
Samuel Strapping Systems
Ultra Ten
1/2
× .023
Samuel Strapping Systems
Ultra Ten
5/8
× .020
Samuel Strapping Systems
Ultra Ten
5/8
× .023
Signode Packaging Systems
Apex Plus
1/2
× .020
Signode Packaging Systems
Apex Plus
5/8
× .020
Signode Packaging Systems
Apex Plus
3/4
× .020
Signode Packaging Systems
Apex Plus
3/4
× .023
Note: This table corresponds with the AAR Open Top Loading Rules Manual, Section 1, Table 17.9. Current as of July 10, 2013.
6.1.5 Use metal protectors, such as corner guards or plates, sufficient to provide a suitable radius
to protect straps at all points on lading having sharp edges and/or sharp corners.
6.1.6 Use tensioning and sealing equipment properly. Check the tools periodically to ensure their
efficiency.
6–2
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
BLOCKING AND BRACING MATERIALS
6.1.7 Sealless band joints are those joints that do not require the use of separate metal seals.
Figure 6.3 shows a sealless package band joint made with approved sealing equipment for 12, 58, 34,
and 1 14 in. band sizes. Table 6.4 contains a list of approved sealing equipment of this type.
Figure 6.3 Triple die-cut sealless joint
Table 6.4 Approved steel strapping sealless tool manufacturers
(triple die-cut sealless joint)
Approved Band Sizes (in.)
1/2
5/8
3/4.
Acme Packaging Corp. Model G9G
X
X
X
Fromm
X
X
X
X
X
X
Manufacturer
Fromm A-26
11/4
X
Josef Kihlberg Model 1219
Orgapack (Borbe Wanner)
X
X
X
X
Samuel G9G Series
X
X
X
X
Titan/Samuel
X
X
X
Signode Packaging Sys.
X
X
X
Titan/A.J. Gerrard
X
Note: This table corresponds with the AAR Open Top Loading Rules
Manual, Section 1, Table 17.5. Current as of May 25, 2010.
6.1.8 Figure 6.4 shows a sealless joint with a fourth die-cut in reverse for 1 14-in. package bands
when made with approved sealing equipment. Refer to Table 6.5 for a list of approved sealing
equipment of this type.
Figure 6.4 Sealless joint with reverse die-cut
Table 6.5 Approved sealless tool for 1 14 in. steel strapping bands
(sealless joint with reverse die-cut)
Orgapack (Borbe Wanner)
Signode Packaging Sys. Model SPC-114
ZR Tool Combination Tool Model ZL90-1
Sund Birsta AB—Model # SBH5
Note: This table corresponds with the AAR Open Top Loading Rules
Manual, Section 1, Table 17.6. Current as of February 27, 2012.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
6–3
BLOCKING AND BRACING MATERIALS
6.2 Nonmetallic Strapping
See Tables 6.6 through 6.8. For the latest updates to these tables, go to TTCI’s Web site at
http://www.aar.com/standards/open_top_loading_approvals.php
6.2.1 Tables 6.6 and 6.7 list bonded or woven polyester cord strapping approved for use in closed
cars for approved loading and securement methods in which the use of polyester cord strapping is
specified.
Table 6.6 Approved Type IV polyester strapping (page 1 of 2)
Approved Size in. (mm)
Manufacturer/
Distributor
AAR ID
Approved
Through
(Mo/Yr)
.035
5/8 (15.9)
.038
3/4 (19.1)
1 (25.4)
.040
.040
.050
.040
.050
X
Xb/
Xb/
1 1/4 (32.0)
.032
.040
.050
Approved
Joint Type
30
Acmea/
2/10
X
X
X
11
Acmea/
12/15
Xc/
Xc/
Xc/
H, F
11
Acmea/
5/15
X
F
82
Allstrap Strapping Systems LLC
2/14
X
F
58
DuBose Strapping Inc.
6/15
X
X
X
58
DuBose Strapping Inc.
6/15
Xc/
Xc/
Xc/
Xb/
X
Xb/
Xb/
H, F
Xb/
H, F
Xb/c/
H, F
59
Cyklop—Brazil
1/15
X
X
X
F. S
59
Cyklop—Germany
1/15
X
X
X
F. S
53
Polychem Corp.
9/13
X
X
H, F
53
Polychem Corp.
2/16
Xc/
Xc/
F
53
Polychem Corp.
2/15
X
X
F
22
Samuel Strapping Sys.d/
9/15
X
X
X
X
H, F
22
Samuel Strapping Sys.d/
3/16
Xc/
Xc/
Xc/
11
Signodea/
5/15
11
Signodea/
6/16
X
11
Signodea/
12/15
Xc/
11
Strapexa/
6/16
X
11
Strapexa/
12/15
Xc/
11
Strapexa/
5/15
14
Itistrap S.r.1.
12/14
57
Mallis Strapping Systems—USA
12/15
X
X
57
Mallis Strapping Systems—USA
7/14
Xe/
Xe/
51
Gerrard-Ovalstrappingd/
9/15
X
X
X
51
Gerrard-Ovalstrappingd/
3/16
Xc/
Xc/
Xc/
60
Teufelberger GesmbH—Austria
6/16
X
X
X
63
Hangzhou Fuyang Hua Chen Plastic Co. Ltd.
—China
12/15
X
X
64
Interpet S.A.
3/16
Xb/
X
X
64
Interpet S.A.
3/16
Xc/
Xc/
Xc/
Xb/
Xb/
H, F
X
Xb/
Xb/
X
X
Xc/
Xc/
X
X
Xc/
Xc/
X
Xb/
Xb/
X
H, F
H, F
Xb/
H, F
H, F
X
F
X b/
X b/
H, F
X
H, F
Xb/
Xb/
Xb/
U.S. Strapping Company
3/16
X
X
Strapack Embalagens Ltda/
1/14
X
X
X
67
NHXXL Synthetic Fibre Inc.
7/13
X
X
67
NHXXL Synthetic Fibre Inc.
2/15
H, F
Xb/
Xb/
Xb/
Xb/
Xe/
Xe/
H, F
Xc/
Xc/
Xc/
H
Xb/
H,F
F
F
X
Fromm Plastics GmbH Germany
2/15
68
Fromm Plastics Asia Co., LTD.
2/15
Xb/
27
Green Span Packaging System—Indonesia
06/16
X
12
Haining Tricot Plastic
12/13
X
40
Yongheng Polyester Strap Co.—China
9/14
X
H, F
F
66
68
F
F
X
65
Xb/
F
Xb/
X
X
Xb/
6–4
Xb/
Xb/
X
Xb/
X
X
F
X
Xb/
Xb/
Xb/
Xb/
H, F
X
Xb/
Xb/
Xb/
Xb/
H, F
F
X
F
F
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
BLOCKING AND BRACING MATERIALS
Table 6.6 Approved Type IV polyester strapping (page 2 of 2)
Approved Size in. (mm)
Manufacturer/
Distributor
AAR ID
Approved
Through
(Mo/Yr)
.035
5/8 (15.9)
.038
3/4 (19.1)
.040
.040
.050
X
X
41
Dae Yang Straps Co LTD.
06/16
X
X
42
JSC Polivektris
06/16
X
X
1 (25.4)
.040
.050
1 1/4 (32.0)
.032
.040
Approved
Joint Type
.050
F
F
Strapping in the table above may be used only where specified in an approved figure or as an allowable substitution for steel banding under the applicable figures in
Section 5.
Strapping in the table is for smooth-sided polyester plastic-type strap only unless otherwise denoted.
a/
b/
c/
d/
Associated with Illinois Tool Works (ITW) as a manufacturer employing common production procedures and specifications.
Friction-weld only approved joint type.
Embossed-type strap
Associated with Samuel Manutech Strapping Companies as a manufacturer employing common production procedures and
specifications.
e/ Heat-sealed-only approved joint type
Note: This table corresponds with the AAR Open Top Loading Rules Manual, Section 1, Table 19.1. Current as of July 10, 2013.
Table 6.7 Approved Type 1A bonded polyester strapping
AAR ID (Part No.)
Grade 3 a/
Grade 4 b/
Grade 5 a/,b/
Manufacturer/
Distributor
Approved
through
(Mo/Yr)
MBS (lb)
1,585
Caristrap Weatherguard
04/15
CW-60 WGHD
Caristrap Weatherguard
05/15
Carolina Strapping
GatorSTRAP
03/16
Carolina Strapping
MakoSTRAP
06/15
ITW/Signode Avistrap
05/14
Pacific Strapping
06/13
AAR-79 (P104)
Southern Strapping
07/15
AAR-78 (AW-105)
Southern Strapping
07/15
AAR-78
(TY-105)
TAPEX American Corp.
07/14
TAPEX American Corp.
07/14
TAPEX American Corp.
07/14
Cordstrap USA Inc.
02/16
R.C. Packaging
Systems Inc.
01/15
R.C. Packaging
Systems Inc.
12/15
AAR-38 (RC105)
Buckle
Redback Industries
03/16
AAR-39
(RBC105)
(CW105RB
Buckle
MBS (lb)
2,100
MBS (lb)
3,285
MBS (lb)
4,400
MBS (lb)
4,200
CW-105 WOJ
MBS (lb)
5,400
Approved
Joint Type
CW-125 WOJ
Buckle
AAR-80
CS-2025
Buckle
CSB 9093
(CS2055)
CW-105 WGSD
AAR-80
CS-2025
Buckle
AAR-80
CS-2040
AAR-80
CS-5080
AAR-11
Buckle
AAR-11
AAR-11
Buckle
Buckle
Buckle
AAR-78 (AW125)
Buckle
AAR-1
(65WLMD)
Buckle (170)
B6-OT
AAR-1 (105WXH)
AAR-77 (CC105)
AAR-38
AAR-38
Ladder Buckle
FCT-10 (FLB)
AAR-77 Cordlash 95
AAR-1
(125WXH)
Ladder Buckle
FCT-12 (FLB)
AAR-77
Cordlash 105
Buckles
CB10 (CC105)
HDB10N (Cordlash 95 and105)
AAR-38
Buckle
Type IA strapping consists of longitudinal polyester cords bonded with a plastic binder to form a nonwoven material or longitudinal polyester cords woven with a weft
thread and treated with a plastic binder to form a woven material.
a/ Strapping is acceptable for use as a substitution for steel package bands up to and including 34 in. × .028 in. only where substitution
is specifically permitted in lumber figures in the Open Top Loading Rules Manual, Section 5.
b/ Strapping is acceptable for use as a substitution for steel bands up to and including 114 in. × .031 in. under applicable lumber figures
where substitution is specifically permitted in the Open Top Loading Rules Manual, Section 5, unless otherwise specified.
Note: This table corresponds with the AAR Open Top Loading Rules Manual, Section 1, Table 19.2. Current as of March 20, 2012
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
6–5
BLOCKING AND BRACING MATERIALS
Table 6.8 Approved Type 1A polyester strapping Grades 6 and 7
Grade 6
Grade 7
Approved
AAR ID (Part
MBS lb (N)
Joint-Type
No.)
11,000 (48,930) Hook/Buckle
Approved
through
(Mo/Yr)
AAR ID
(Part No.)
MBS lb (N)
7,700 (34,265)
Cordstrap USA Inc.
3/14
AAR-77
X
AAR-77
X
CDBH12 or
CDBH12Extended
HDB12N, DLB12N, or
DLB12N200
Carolina Strapping
GatorLASH
3/16
AAR-80
CS 8040
X
AAR-80
CS 8050
X
CSB9075
CSB9090
CSB9091
ITW / Signode Avistrap
10/13
AAR-11
X
N/A
N/A
FCH-13 (HKB)
FCT-15
Southern Strapping
5/14
AAR-78
X
AAR-78
X
-
SSLB 40
TAPEX American Corp.
7/14
AAR-1
(135WXH)
X
N/A
N/A
FCH-13 (HKB)
FCT-13 (FLB)
Caristrap Int’l
1/15
Carilash
AG40
X
N/A
N/A
—
BN1431
Caristrap Int’l
12/15
Carilash AG50
X
—
BN1431
Manufacturer/
Distributor
Approved
Joint-Type
Buckle
Note: This table corresponds with the AAR Open Top Loading Rules Manual, Section 1, Table 19.3. Current as of March 7, 2013
6.2.2 Refer to the manufacturer’s instructions regarding the proper application of joints.
Figures 6.5 through 6.8 show common methods of joining nonmetallic straps.
Figure 6.5 Threading a wire buckle
6–6
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
BLOCKING AND BRACING MATERIALS
Figure 6.6 Threading a cordstrap CB buckle
Figure 6.7 Threading a ladder-type buckle
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
6–7
BLOCKING AND BRACING MATERIALS
TAPEX FCT-12 BUCKLE
Figure 6.8 Threading a Tapex FCT-12 buckle
6.2.3 Figure 6.9 shows a nonmetallic strap attached to permanent side-wall anchors. Attach
straps a minimum of 3 ft behind the face of the load.
WRAPPING STRAP ON WALL
ANCHOR FOR CONVENTIONAL
STRAP APPLICATION. USE
THREE WRAPS OF STRAPPING
AROUND THE WALL ANCHOR.
USE STRAP RETAINER TO
SECURE STRAP TO WALL
ANCHOR.
Figure 6.9 Attaching Type 1A, Grade 3, 4, or 5 strap to side-wall anchors
6–8
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
BLOCKING AND BRACING MATERIALS
6.3 Web Strap Assemblies
6.3.1 Web strap assemblies (Figure 6.10) are anchored to the car floor using T-hooks inserted into
anchor plates or side walls with wall anchor clips. Use web strap assemblies (strap, ratchets, and
related hardware) with a minimum load rating of 18,000 lb or as specified in a specific loading
method. Tensioning ratchets are located near the side wall.
NOTES:
1. WEBBING MATERIAL: POLYESTER
COLOR: SEE COLOR SCHEDULE
2. ASSEMBLY BREAKING STRENGTH: 18,000–20,000 LB
3. ASSEMBLY WORKING LOAD LIMIT: 6,500 LB
4. EXTRA 16 IN. NECESSARY FOR TWO WRAPS AROUND DRUM
Figure 6.10 Web strap assembly
6.3.2 A synthetic webbing and/or tie-down assembly must be removed from service if any of the
following conditions are present. (Refer to Figure 6.1.1 for illustrations of some sample defect
conditions.)
BROKEN, CRUSHED,
THINNING, OR WORN STITCHING
EXCESSIVE ABRASSION
OR WEAR
KNOTS, KINKS, OR
PERMANENT CREASES
SKETCH 2
SKETCH 3
SKETCH 4
MELTING, CHARRING,
OR WELD SPATTER
OVERSTRESSED FIBERS
OR CHEMICAL DAMAGE
BROKEN OR WORN STICHING IN THE
LOAD-BEARING SEW PATTERN
WEB DAMAGE
AT FITTING
SKETCH 5
SKETCH 6
SKETCH 7
SKETCH 8
HOLES, TEARS,
CUTS, SNAGS
SKETCH 1
Figure 6.11 Sample web defects
6.3.2.1 Holes, tears, cuts, snags, or embedded particles in the webbing.
6.3.2.2 Broken, crushed, thinning, or worn stitching in the load-bearing stitch patterns.
6.3.2.3 Excessive abrasion or wear.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
6–9
BLOCKING AND BRACING MATERIALS
6.3.2.4 Degradation due to ultraviolet radiation as indicated by excessive fading in conjunction
with evidence of overall frayed yarn fibers or other detectable fabric deterioration.
6.3.2.5 Knots in any part of the webbing.
6.3.2.6 Melting, charring, or weld spatter on any part of the webbing.
6.3.2.7 Acid or alkali burns or other chemical contamination that inhibits or may inhibit the
performance of the webbing.
6.3.2.8 Any other condition that appears to degrade the strength of the webbing or other
component of the tie-down assembly (e.g., crushed areas, severe abrasions, etc.).
6.3.2.9 When a tie-down assembly contains broken or nonfunctioning fittings, tensioning devices,
or hardware.
6.3.2.10 When a winch pawl fails to operate freely and is not capable of retaining strap tension by
engaging the ratchet wheel under gravity.
6.4 Cargo Nets
6.4.1 Use only cushion-equipped boxcars specially equipped with side-wall anchors to
accommodate cargo net straps.
6.4.2 Inspect the cargo net and associated assemblies for suitability before loading. Worn,
missing, or corroded components and/or stitching may be cause for rejection.
6.4.3 Use cargo net assemblies (strap, ratchets, and related hardware) as specified in specific
loading method(s). See Figure 6.12 and 6.13.
12-IN.-WIDE STRAPS AT CORNERS
3-IN.-WIDE STRAPS
CONNECT TO SIDEWALL
3-IN.-WIDE STRAPS
CONNECT TO SIDEWALL
RATCHET ASSEMBLY SIDE VIEW
Figure 6.12 Attaching cargo nets
6–10
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
BLOCKING AND BRACING MATERIALS
Figure 6.13 Cargo net attachment —top view
6.5 Lumber
6.5.1 Use properly seasoned lumber for car bracing and blocking. Do not use green lumber
because it does not have the strength or stiffness qualities of dry lumber. Green lumber under
certain conditions will give off quantities of moisture that can have harmful effects on some
commodities loaded in the cars.
6.5.2 Properly store lumber used for blocking and bracing from the elements to prevent rotting,
decaying, or checking, which may affect its strength.
6.5.3 When selecting the size of lumber for bracing and blocking, give consideration to the
weight, size, and nature of the commodity to be secured within the car.
6.5.4 Select all blocking and bracing material from sound lumber free from cross-grain, dry rot
and knots, knotholes, and checks or splits, which will affect its strength or interfere with proper
nailing. See Figure 6.14.
CUT-OFF KNOTS THAT INTERFERE WITH
NAILING AT DOTTED LINE, AS SHOWN
LARGE KNOTS WEAKEN MEMBERS. CUT
OFF AS SHOWN AND USE SHORT PIECES
FOR CLEATS
NEVER USE LUMBER WITH
CROSS-GRAIN FOR STRUCTURAL
MEMBERS
DO NOT REJECT LUMBER WITH SMALL
AMOUNT OF BARK
Figure 6.14 Selecting wood blocking and bracing material
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
6–11
BLOCKING AND BRACING MATERIALS
6.5.5 Relative strength values of lumber, such as stiffness, bending, compression strength
qualities, and the ability to resist shocks, are important. Equally important are the factors of nailholding qualities and resistance against splitting.
6.5.6 Dimensions shown in Table 6.9 are the minimum commercial sizes for lumber to be used in
the construction of center gates, end gates, and blocking. Table 6.10 shows species of wood most
commonly used.
Table 6.9 Standard thicknesses for yard lumber
Nominal Thickness
Rough Lumber
Actual Thickness
S4Sa/
2 in. × 4 in.
1 ½ in. × 3 ½ in.
2 in. × 6 in.
1 ½ in. × 5 ½ in.
2 in. × 8 in.
1 ½ in. × 7 ¼ in.
a/ Surfaced four sides. Standard lengths are usually 6 to 24 ft in increments of 1 ft.
Table 6.10 Species of wood most commonly used for bracing
Group
Soft Woods
Specific Group II and III
Gravity Medium Woods
Specific Group IV
Gravity Hard Woods
Specific
Gravity
Cottonwood
0.37 Douglas Fir
0.51 Ash
0.64
Fir, Balsam
0.41 Hemlock
0.44 Beech
0.67
Fir, White
0.42 Maple, Hard Black
0.62 Elm
0.66
Pine, Lodge Pole
0.43 Larch
0.59 Hickory
0.80
Pine, Ponderosa
0.42 Pine (So. Yellow)
0.59 Maple (Hard) Sugar
0.68
Pin. White Eastern
0.37 Pine (Norway)
0.47 Oak, White
0.71
Pine. White Western
0.42 Cedar (Port Oxford)
0.44 Oak, Red
0.66
Spruce, White
0.45 Sweet Gum
0.53
Poplar, Yellow
0.43
For a more complete listing of hardwoods and lumber, see the AAR Open Top Loading Rules
Manual, Section 1, Appendix D, “Material Mechanical Properties.”
6.5.7 Lumber used in car bracing is in Group II and III woods. Use commercial sizes. When soft
woods (Group I) are substituted, use a larger commercial size per Table 6.11.
Table 6.11 Substitution guide
6–12
Group II and III Woods
Medium
Group I Woods
Soft
2 in. × 3 in.
2 in. × 6 in.
2 in. × 4 in.
2 in. × 8 in.
2 in. × 6 in.
3 in. × 6 in.
3 in. × 4 in.
4 in. × 6 in.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
BLOCKING AND BRACING MATERIALS
6.6 Nails and Nailing
6.6.1 Sizes of nails shown for the construction and assembly of blocking and bracing and the
securing of same within the car are based on use of common nails. Table 6.12 shows the sizes of
common nails, power-driven nails, and power-driven staples that are used in car bracing.
Table 6.12 Common nails, power driven nails, and power driven staples
Common Nails
Power-Driven Nails
Power-Driven
Staples
Size
Penny
Weight
Length
(in.)
Wire
Diameter
(in.)
Length
(in.)
Wire
Diameter
(in.)
Length
(in.)
Wire
Diameter
(in.)
10-D
3
0.148
3
0.120
3, 3 ½
0.80
12-D
3¼
0.148
3¼
0.131
—
—
16-D
3½
0.162
3½
0.131
3½
0.80
20-D
4
0.192
4
0.145
3½
0.80
30-D
4½
0.207
4¾
0.165
—
—
6.6.2 Consider the relation of the number, size, and kind of nails to the size and kind of lumber
used in blocking and bracing. Use sufficient nails because the strength of bracing increases
directly with the number of nails. Do not use nails where they will be in direct tension, but
preferably in lateral resistance. See Table 6.14 for the lateral resistance of nails driven in boxcar
floors.
6.6.3 Drive nails into the side grain of lumber where there is 50% more holding power than when
driven into the end grain. The probability of the wood splitting is also less. Drive all nails straight.
Table 6.13 Lateral resistance of nails when driven through 2-in.-thick floor blocking
and into boxcar floor (lb)
Size of Common Nail (D)
8
10
12
16
20
344
733
916
956
1603
Load applied at 90° angle to the shank or direction of driving of nail point in
the securing wood.
6.6.4 To facilitate driving, to prevent splitting, and to increase the holding power of the nail,
predrill holes slightly smaller than the diameter of the shank of the nail.
6.6.5 Use nails long enough to penetrate, hold, and secure floors with other bracing and blocking
members.
6.6.6 Nails two pennies smaller than those used for medium or soft wood may be used for
extremely hard woods listed in Group IV of Table 6.10.
6.6.7 When using pneumatic automatic nailers, staplers, or other devices, sizes of nails may be
less than those specified if the number driven is increased by one third and the size substitution in
Table 6.14 is used.
Table 6.14 Substitution of power-driven nails or staples
Common Nail
Power-Driven Nail
Power-Driven Staple
Leg Length
10-D
8-D or 10-D
3 in. or 3¼ in.
16-D, 20-D
16-D or 20-D
3½ in.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
6–13
BLOCKING AND BRACING MATERIALS
6.7 Pneumatic Dunnage
6.7.1 Table 6.15 defines five levels of performance for pneumatic dunnage: Level 1 for pneumatic
dunnage as lateral void fillers (and load securement in certain intermodal applications) and Levels
2–5 for pneumatic dunnage as lengthwise void fillers in flat platen-type applications with varied
performance requirements. Pneumatic dunnage meeting Level 2–5 requirements fulfills all
Level 1 requirements.
Table 6.15 Performance level application guide
Level 1
For filling lateral voids, primarily in intermodal loads
Level 2
For filling lengthwise voids in loads weighing up to 75,000 lb
Level 3
For filling lengthwise voids in loads weighing up to 160,000 lb
Level 4
For filling lengthwise voids in loads weighing up to 216,000 lb and
horizontal applications in approved roll paper loading methods
weighing up to 190,000 lb
Level 5
For filling lengthwise voids in loads weighing up to 216,000 lb and
horizontal applications in approved roll paper loading methods
6.7.2 Usage guidelines: follow the manufacturer’s instructions on care and storage of bags prior
to use. Inflate bags with an approved inflator, in accordance with the manufacturer’s instructions.
6.7.3 After inflation, check to see that dunnage bags are approximately the same size as the face
of the load. Do not extend the dunnage bag beyond the face of the load. See Figure 6.7.
6.7.4 Use buffer material of sufficient strength to prevent it from conforming to dunnage bag
contour, to prevent chafing, to prevent dunnage bag from crushing load at proper inflation
pressure, and to prevent lading from damaging dunnage bags.
6.7.5 Use buffer material equal or slightly larger in size than face of lading. Have lading adjacent
to bag(s) nearly equal in height on each side of bag.
6.7.6 Inflation pressure may vary from 2 psig to 10 psig depending on the nature of lading and
the level of air bag used.
6.7.7 Void size after inflation will be from 4 in. to 12 in. See applicable commodity publications
for possible exceptions to this limitation.
6.7.8 Use inflatable dunnage to fill lengthwise voids of 4 to 18 in. after inflation for bales and
bags. For fiberboard box goods, keep the void as narrow as practical, preferably 4 to 10 in. to a
maximum of 12 in. after inflation. Inflate to 3 psi to 6 psi depending on the nature of the lading,
and use an air gauge to ensure proper inflation pressure.
6.7.9 Install bag(s) so that the bottom(s) will be a minimum of 1 in. above the floor after inflation.
Apply protective material (e.g., fiberboard) between the bag and floor.
6.7.10 Use hold-down methods when necessary to prevent bag displacement from the void area.
6.7.11 Use an air gauge to ensure prescribed air pressure at inflation. Recheck air pressure onehalf hour after inflation for leakage.
6.7.12 Use clean and dry air to fill dunnage bags.
6.7.13 Do not use bags in tandem (back-to-back). Do not use dunnage bags to fill more than one
lengthwise void in a car.
6.7.14 Use two bag systems unless otherwise specified.
6–14
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
BLOCKING AND BRACING MATERIALS
6.7.15 When loading single layer units, use one bag positioned horizontally. For units loaded two
layers high, use two bags positioned vertically or horizontally adjacent to each other. Normally a
48- by 96-in. bag is compatible with side-by-side unit loads measuring 48 in. long by 40 in. wide to
54 in. high. See Figures 6.15 and 6.16.
12 IN. MAXIMUM
AFTER INFLATION
HEIGHT EQUAL TO THE
HEIGHT OF THE LOAD
PNEUMATIC DUNNAGE AND BUFFER
SHEETS OR FILLER PANELS
1 IN. MINIMUM ABOVE CAR FLOOR
Figure 6.15 Pneumatic dunnage installed vertically
12 IN. MAXIMUM
AFTER INFLATION
HEIGHT EQUAL TO THE
HEIGHT OF THE LOAD
PNEUMATIC DUNNAGE AND BUFFER
SHEETS OR FILLER PANELS
1 IN. MINIMUM ABOVE CAR FLOOR
Figure 6.16 Pneumatic dunnage installed horizontally
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
6–15
BLOCKING AND BRACING MATERIALS
6.7.16 For bags and bales, use a minimum of two sheets of 275-lb double-wall fiberboard buffer
material between each side of dunnage and lading. When bracing fiberboard box goods, use
suitable buffer material between dunnage bags and lading to prevent deformation of the lading.
6.7.17 Reusable dunnage bags intended for use only in filling crosswise (lateral) voids must be
prominently marked by the manufacturer to indicate proper application. Never use bags marked
for this application to fill lengthwise voids.
6.7.18 Leave the door of the car open after loading is completed, and check bag 30 minutes after
installation for leakage.
6.7.19 Use of dunnage bags does not eliminate the need for doorway protection.
6.7.20 For further information, refer to AAR General Information Bulletin No. 9, “Product
Performance Profile for Pneumatic Dunnage.”
6.7.21 Go to http://www.aar.com/standards/dpls/pfds/PPPPD_Verification_List.pdf for the most
current “Product Performance Profile for Pneumatic Dunnage Product Verification List.”
6.8 Friction Mats
Friction mats are used between freight and the railcar and between layers of freight to increase
resistance to lateral and longitudinal movement. For freight loading applications, friction mats are
most commonly manufactured from either masticated or rebonded rubber, in thicknesses up to
¼ in. Use friction mats as specified in specific loading methods.
6–16
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.0 GATES, FILLERS, SEPARATORS, AND DIVIDERS
Those materials used to fill the lengthwise space in a car, not occupied by the lading or used to
segregate the lading, are designated according to types: end gates, divisional or intermediate
gates, center gates, fillers, or dividers.
7.1 Gates
7.1.1 Figure 7.1 shows how divisional gates can be secured in position with steel straps.
ANCHOR NOT LESS THAN
3 FT FROM FACE OF GATE
SIDE WALL POSTS
2 IN. × 4 IN. UPRIGHTS
1 IN. × 4 IN. HORIZONTALS
REVERSE STRAPS ARE HELD IN PLACE ON
REAR FACE OF THE GATE. AFTER THE MAIN
STRAPS HAVE BEEN PARTIALLY TENSIONED
AND THE LOAD DRAWN TIGHT, FASTEN THE
REVERSE STRAPS TO THE CAR SIDE WALL
ANCHORS AND COMPLETE TENSIONING.
Figure 7.1 Divisional gate
7.1.2 Do not secure divisional gates to car walls when used in floating loads. Space horizontal
members on a divisional gate positioned opposite the intersection between layers of containers.
Construct this type of gate with solid faces as may be required by the type of container or
commodity loaded.
7.1.3 Use center gates to take up the space in the doorway area of the car to prevent a shift in the
load and to permit the ready removal of lading. When a large space is left in the doorway area, use
blocking and bracing, as shown in Figure 7.2.
CENTER GATE CONSTRUCTION
MAY VARY DEPENDING ON LOAD
Figure 7.2 Center gate
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
7–1
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.2 Fillers
7.2.1 Use fillers to square off bowed end walls before car is loaded. See Figure 7.3.
2 IN. × 4 IN. UPRIGHTS
HEIGHT EQUAL
TO OR GREATER
THAN LOAD
1 IN. × 4 IN.
CROSS BRACE
1/2 IN. PLYWOOD OR
EQUIVALENT
2 IN. × 4 IN. END
WALL FILLERS
Figure 7.3 Methods of using fillers to square bowed end walls
7.2.2 Use fillers to fill space not occupied by lading.
7.2.3 Closed-cell honeycomb panels used for lengthwise fillers in loads consisting of multi-unit
resilient lading, such as boxes of food-stuff, tissue, soft paper products, furniture, and appliances,
must have a minimum 1,500 lb/ft2 crush strength (see Figure 7.4).
SPACE FILLED NOT TO EXCEED
8 IN. IN ANY ONE AREA
Figure 7.4 Lengthwise fillers in resilient lading
7.2.4 If the lading is rigid in nature and/or very dense, such as boxes of nuts and bolts, machinery,
metal beams, brick, lumber, and cut paper, lengthwise fillers must have a combined crush strength
as defined below.
7–2
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.2.5 In cushioned cars, lengthwise fillers must have a combined crush strength equal to the
weight of the load being restrained. In standard draft gear cars, lengthwise fillers must have a
combined crush strength equal to twice the weight of the load being restrained. Secure fillers in
position.
7.2.6 For example, if the filler is to be located at the end of a standard draft gear car loaded to
150,000 lb, the combined crush strength of the fillers must be greater than or equal to 300,000 lb.
If two 4- by 8-ft filler panels are used side by side, their combined area is 2 × 4 × 8 ft = 64 ft2. The
required minimum crush strength would equal 300,000/64, or 4,687.5 lb/ft2. See Figure 7.5,
Example 1.
7.2.7 Fillers centered in the same load would require a minimum crush strength of 2,344 lb/ft2.
See Figure 7.5, Example 3.
EXAMPLE 1
EXAMPLE 2
IRE
T
EN
LO
HT
EIG
W
AD
EXAMPLE 3
LENGTHWISE FILLERS
AT END WALL
3/4
LO
HT
EIG
W
AD
LENGTHWISE FILLERS
MIDPOINT IN END OF LOAD
1/2
L
D
OA
T
IGH
WE
LENGTHWISE FILLERS
AT MIDDLE OF LOAD
Figure 7.5 Lengthwise fillers in rigid lading
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
7–3
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.2.8 Fillers may be reinforced for special load applications such as intermediate bulk containers
(see Figures 7.6).
THIS AREA MUST BE
CONSTRUCTED OF
MAXIMUM 9 IN. CELL
LINERBOARD
LOCATIONS WHERE MINIMUM COMPRESSION
STRENGTH OF 6,000 LB/FT2 MUST BE MET
AT A MINIMUM, APPROPRIATELY SIZED BLOCKS
OF SUCH STRENGTH MUST BE LOCATED AS
ILLUSTRATED
Figure 7.6 Reinforced lengthwise filler panel
7.2.9 Figure 7.7 shows examples of two types of fillers for lengthwise space.
CORRUGATED VOID FILLER TO FILL LENGTHWISE SPACE.
ARROWS INDICATE THE DIRECTION OF CORRUGATIONS.
REUSABLE POLYETHYLENE FILLER
Figure 7.7 Lengthwise void fillers
7.2.10 Lengthwise filler material must be tall enough to cover the full height of the void from the
bottom of the void to the top. If smaller pieces of culled material are used, they must be laminated
or joined with a consistent width from the bottom to the top of the void for which they are intended
to protect.
7–4
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.2.11 Contour buffer pads are fillers designed to help prevent the displacement of pneumatic
dunnage in roll paper loads (Figure 7.8). Buffer pads are placed on each side of the voids. The
contour side of the pads face the rolls with the flat side adjacent to the dunnage. Use buffer pads
that are at least as tall as the dunnage used. Minimum crush strength of 4,500 lb/ft2 is required
for buffer pads.
BUFFER PAD CRUSH STRENGTH = 4,500 LB/FT2
Figure 7.8 Contour buffer pads
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
7–5
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.2.12 When cars are pallet or slip-sheet loaded, load the units against the side walls and apply
lateral void fillers in voids between the unit rows. Units may also be loaded tight against one side
wall and fillers applied between the units and the other side wall, and alternated in opposite ends
(see Figures 7.9, 7.10, and 7.11).
FILLERS
FILLERS
PLACEMENT OF FILLERS IN UNIT LOAD
WHEN CLAMP-TYPE LIFT TRUCK IS USED
FILLERS
PLACEMENT OF FILLERS IN PALLETIZED LOAD
(NOTE: PLACE SIDE-WALL FILLERS ALONG OPPOSITE
SIDE WALL IN OTHER END OF CAR)
FILLERS
PLACEMENT OF FILLERS WHEN PALLETS
ARE LOADED AGAINST SIDE WALLS
PLACEMENT OF FILLERS WHEN PALLETS ARE CENTERED
Figure 7.9 Use of crosswise fillers
7–6
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
GATES, FILLERS, SEPARATORS, AND DIVIDERS
COLLAPSIBLE
HANGING HONEYCOMB
INTERLOCKING FLANGED SHEETS
FLANGED TUBES INTERLOCKED WITH
FLANGED SHEET
Figure 7.10 Examples of fillers used to fill crosswise space
MOLDED PLASTIC REUSABLE FILLER
HANGING HONEYCOMB FILLER USED TO
FILL CROSWISE SPACE
Figure 7.11 Lateral void fillers
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
7–7
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.3 Separators
7.3.1 Use separator sheets to protect the top of units when stacked (see Figure 7.12).
SEPARATOR
SHEET
PROTECT BOTTOM LAYER
UNITS FROM STACKED
PALLETS WITH SEPARATORS
Figure 7.12 Unitized double layer bag or bale loads
7.3.2 Polyethylene foam pads may be used to separate lading (e.g., metal coils).
7.3.3 Pads are typically 54 in. high by 24 in. wide and 3¼ in. thick at the center of the pad. The
polyethylene pads have a density of 4 lb/ft3.
7.3.4 Type A (Figure 7.13): For use between coils. Contoured on each side with two 8-in.-long by
34-in.-diameter plastic tubing “legs” capped off with 1-in. rubber cane tips inserted at the bottom of
each side to elevate the pad above the adjacent deck boards.
7.3.5 Type B (Figure 7.14): For use between coils and the end wall or bulkhead. Contoured on one
side only. Place flat side against end wall or bulkhead.
CONTOURED ON BOTH SIDES
FOR USE BETWEEN COILS
TYPE A
TYPE B
CONTOURED ON ONE SIDE ONLY FOR
USE BETWEEN COILS AND END WALL
OR BULKHEAD
Figure 7.13 Contour polyethylene foam pads
7–8
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.4 Dividers
7.4.1 Separate different type containers lengthwise using plywood sheets or equivalent material
of sufficient height to protect the tallest stack of containers. See Figure 7.14.
7.4.2 Separate different sizes of the same type of containers by divider sheets. See Figure 7.15.
DIVIDER SHEETS
Figure 7.14 Plywood divider sheets
between different lading types
Figure 7.15 Fiberboard divider sheets
between similar lading types
7.4.3 The construction and quantity of properly installed divider sheets will vary based on many
factors (e.g., density of product and weight of load). The following are the minimum standards for
use of divider sheets in cars that do not have cushioning devices or load restraining devices.
Shippers are expected to cooperate with carriers when it can be demonstrated that additional use
of divider sheets is necessary to avoid excessive damage.
7.4.4 When shipping containers of significant height differences or when bags/bales and boxes
are loaded in cars that do not have cushioning devices or load-restraining devices, use corrugated
or solid fiberboard divider sheets where these differences occur within the load. The divider sheets
may also absorb some of the creasing that would otherwise appear on the shipping containers. Use
corrugated or solid fiberboard divider sheets approximately the same width and height as the load.
When corrugated divider sheets are used, place the divider sheets so that corrugations are vertical
(see Figure 7.16).
DIVIDER SHEET
IMPROPER
PALLETS ARE NOT IN THE SAME
HORIZONTAL PLANE LENGTHWISE IN THE CAR, CREATING
PALLET-TO-PRODUCT CONTACT
PROPER
PALLETS ARE IN THE SAME
HORIZONTAL PLANE, ENSURING
PALLET-TO-PALLET CONTACT
PROPER
SEPARATE PALLETS NOT IN THE
SAME HORIZONTAL PLANE WITH
A DIVIDER SHEET
Figure 7.16 Unitized double-layer pallet loads
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
7–9
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.4.5 For stretch-wrapped units of fiberboard boxes, use divider sheets between doorway stacks to
facilitate unloading. Divider sheets are not required for loads that are stretch-wrapped and meet
the following criteria:
• Weight limitation: Floor layer units must not exceed 35,000 lb; double-decked loads must
not exceed 70,000 lb.
• No lengthwise void is allowed in unit patterns, except for pinwheel or chimney-stacked
units or similar bonded blocks.
7.5 Risers
7.5.1 Risers are used to raise articles of freight to block freight in adjacent stacks and to break
the strata line within a load. Risers are commonly used to raise rolls within paper loads, to either
block incomplete layers or to break the strata line in multiple layer loads of rolls of the same
width.
7.5.2 Risers may be either a strip or pad design (see Figures 7.17 and 7.18). Riser strips made
from laminated corrugated fiberboard or other suitable material should be a minimum of 6 in. tall
by 5 in. wide by 30 in. long, for 40-in.-diameter rolls. Larger diameter rolls require longer risers.
Pad-type risers made from closed-cell honeycomb with reinforced corners should also be a
minimum of 6 in. tall and appropriately sized to fit under the roll without protruding on any side
See Table 7.1.
Figure 7.17 Riser strips
Figure 7.18 Riser pad
Table 7.1 Minimum riser strip and pad sizes for rolls
7–10
Roll Diameter
(in.)
Riser Strip
Length
(in.)
Riser Pad
Length and
Width (in.)
40
30
28
45
34
32
50
38
35
58
40
37
60
45
42
72
54
50
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.5.3 Risers must have a combined crush strength greater than or equal to twice the weight that
they support.
Example 1:
40-in.-diameter by 50-in.-tall rolls stacked two high;
roll weight = 4,500 lb. Rolls are loaded on strip-type risers.
If strip-type risers measuring 6 in. tall by 5 in. wide by 30 in. long are used, their bearing
surface area equals 5 × 30 = 150 in.2 or 1.04 ft2. Because two are required, the total
bearing surface area is 2.08 ft2. Two rolls at 4,500 lb each equals 9,000 lb. Risers need to
be able to support twice the weight or 18,000 lb. 18,000 lb divided by 2.08 ft2 yields
minimum compression strength of 8,654 lb/ft2.
Example 2:
40-in.-diameter by 50-in.-tall rolls stacked two high;
roll weight = 4,500 lb. Rolls are loaded on pad-type risers.
If pad-type risers measuring 6 in. tall by 28 in. square are used, their bearing surface
area equals 28 × 28 = 784 in.2 or 5.44 ft2. Two rolls at 4,500 lb each equals 9,000 lb.
Risers need to be able to support twice the weight or 18,000 lb. 18,000 lb divided by
5.44 ft2 yields a minimum compression strength of 3,309 lb/ft2.
7.5.4 Do not place risers in between roll layers anywhere within a load. Risers should be placed
only under rolls on the floor.
7.5.5 Use risers under rolls in the doorway area only when they are necessary for dock plate
clearance. Risers used in the doorway area should be no more than 2 in. high. Place risers only on
the floor—never between stacked rolls.
7.5.6 Place strip risers so that their longest dimension is lengthwise of the car.
7.5.7 Never extend risers beyond the outer edge of the roll.
7.5.8 Laminated risers are acceptable but must meet the minimum required crush strength.
7.5.9 Do not stack and tape risers together. Only pad-type risers glued together are considered
laminated risers. If glued together, the manufacturer of product should provide glue or
specifications for appropriate adhesive.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
7–11
GATES, FILLERS, SEPARATORS, AND DIVIDERS
7.5.10 In loads of multiple layers, use risers placed beneath rolls midway between the ends of the
car and the doorway to break the layer strata line (see Figure 7.19). This will help to prevent rollover ride, reduce edge damage opportunities, and increase the performance of dunnage bag
application.
RISERS
Figure 7.19 Risers used to break strata line
7–12
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
LOAD SECUREMENT
8.0 LOAD SECUREMENT
8.1 Floor Blocking
8.1.1 Floor blocking is not recommended for lengthwise load securement in boxcars with steel
floors.
8.1.2 Guide rails may be used to prevent crosswise movement of lading loaded in a single layer or
sufficiently unitized so as to prevent lateral movement (see Figure 8.1).
CROSSPIECES
GUIDE RAILS
Figure 8.1 Guide rails used for lateral bracing
8.1.3 Guide rails may be either nailed to the car floor or held in position by crosspieces nailed to
the guide rails.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
8–1
LOAD SECUREMENT
8.2 Anchored Loads
8.2.1 The anchored load provides rigid bracing of the lading by the use of straps secured to the
car side wall permanent anchors.
8.2.2 Use anchors that are at least 3 ft from face of load.
8.2.3 If the lading can contact the anchors, cover the anchor plates with fiberboard or several
thicknesses of heavy paper.
8.2.4 Drape cars with steel straps in preparation for loading, with the steel straps held
temporarily in position against the side walls with tape (see Figure 8.2).
STRAPS
SECURED TO
CAR SIDE WALLS
TAPE
TAPE
FASTEN STRAP
OUTSIDE CAR WHILE
LOADING
Figure 8.2 Draping a car for an anchored load
8.2.5 When two or more straps are used, tension and seal straps simultaneously to equalize the
tension on all straps.
8.2.6 Provide corner or edge protection to prevent damage to the lading due to pressure from
straps.
8.2.7 Use strap hangers, tape, or other means to prevent straps from slipping or dropping out of
position while in transit.
8.2.8 Figure 8.3 shows a completed anchored load and the applications of steel straps to a gate
with truss-block construction.
STRAPS SECURED TO
SIDE WALL ANCHORS
STAPLE STRAP TO GATE
TENSION AND SEAL
ANCHOR STRAPS NOT LESS
THAN 3 FT FROM FACE OF GATE
TRUSS BLOCKS APPLIED TO
GATE FOR HEAVY LOADS
Figure 8.3 Anchored load
8–2
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
LOAD SECUREMENT
8.2.9 Web strap assemblies that attach to the side-wall anchors may be used to secure lading in
the ends of the car. The combined minimum breaking strength of the number of straps used must
be equal to or greater than the weight of the lading restrained. When lading height-to-base ratio is
greater than 2, apply half of the straps on the upper one third of the lading, as shown in
Figure 8.4.
RATCHETS FOR
TENSIONING STRAPS
Figure 8.4 Anchored load using web strap assemblies
8.3 Incomplete Layer Bracing
8.3.1 Avoid incomplete layers in shipments whenever possible. However, when incomplete layers
have to be loaded, protect the lading from lengthwise movement, as shown in Figure 8.5. When
using this method, secure bottom layers rigidly in position.
Figure 8.5 Incomplete layer bracing—rigid loads
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
8–3
LOAD SECUREMENT
8.3.2 To prevent possible contact and damage between lower layer lading and the incomplete
layer, elevate the lading immediately in front of the incomplete layer on risers and secure with
straps anchored to the car side walls, as shown in Figure 8.6.
STRAPS SECURED
TO CAR SIDE WALLS
RISERS 6 IN. MINIMUM
HEIGHT
Figure 8.6 Incomplete layer bracing—paper roll
8–4
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
DOORWAY PROTECTION
9.0 DOORWAY PROTECTION
9.1 Rule 7, AAR Circular No. 42-K states the following:
“When there is a possibility of lading falling or rolling out of doorway or coming in contact with
sliding or plug-type side doors, openings must be protected with wood doorway protection, steel
straps, or other material of sufficient strength and number and adequately secured. Cars equipped
with plug-type doors loaded with cylindrical items such as rolls of paper or drums require doorway
protection unless specifically exempted by applicable commodity guides.”
9.2 Wood doorway protection may be applied for single-layer loads, as shown in Figure 9.1.
MINIMUM 4 × 4 IN. LUMBER OR TWO LAMINATED 2
× 4 IN. PIECES. CUT LENGTH SLIGHTLY LONGER
THAN DOOR WIDTH AND WEDGE IN PLACE.
Figure 9.1 Wood doorway protection for a single-layer load
9.3 Use steel straps for doorway protection. For heavy freight, use 1¼- by 0.029-in. steel straps
(or equivalent). See Figure 9.2. Place one steel strap opposite each layer, attached to permanent
side-wall anchors, and use sheets of fiberboard placed over straps and anchors as needed to protect
lading.
FIBERBOARD
SEAL
1¼ × 0.029 IN. STEEL STRAP
OR EQUIVALENT
Figure 9.2 Steel strap doorway protection
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
9–1
DOORWAY PROTECTION
9.4 The nonmetallic straps listed in Table 9.1 have been tested and found acceptable for use as a
substitute for 1¼- by 0.029-in. steel straps in doorway protection applications.
Table 9.1 Substitution rate for nonmetallic strap as doorway protection
Company/Size/Strap Designation
Application
Substitution Rate
Avistrap 1 12 in. PW 120EH
Belt Type (Looped)
3 straps for each steel strap
Caristrap 1 14 in. 105WGSD
Conventional
4 straps for each steel strap
Caristrap 1 14 in. 105WGSD
Belt Type (Looped)
3 straps for each steel strap
Carolina Strapping 1 14 in. CS-2040
Belt Type (Looped)
3 straps for each steel strap
Carolina Strapping 1 12 in. CS-2055
Belt Type (Looped)
2 straps for each steel strap
Cordstrap 1 14 in. CC 105a/
Belt Type (Looped)
3 straps for each steel strap1
Tapex 1 12 in. 125 WXXH
Belt Type (Looped)
2 straps for each steel strap
Southern Strapping 1 14 in. TY2AW 105 Belt Type (Looped)
3 straps for each steel strap
Caristrap Carilash AG50
2 straps for each steel strap
Belt Type (Looped)
a/ CC 105 strap was applied during testing with a CT 32 PN pneumatic tensioning tool supplied by Cordstrap.
NOTE: The application of nonmetallic straps as a substitute for 1 14-in. by 0.029-in. steel strap is
restricted to maximum door openings of 10 ft in width.
9.5 Install straps across the door opening between the doorposts, as shown in Figure 9.3. Use the
proper number of straps. Apply uniform tension to all straps so that all straps share the load
equally.
STRAP ENDS TENSIONED
AND SEALED
CONVENTIONAL STRAP APPLICATION
STRAP ENDS TENSIONED
AND SEALED
BELT-TYPE STRAP APPLICATION
Figure 9.3 Conventional and belt-type strap applications
9.6 Straps must be tensioned using the correct tensioning tools in accordance with the
manufacturer’s instructions. It is important that the buckle be applied properly to maintain strap
tension.
9.7 The strap must be clearly marked with the strap I.D. in accordance with the strap-marking
requirements of AAR Circular 42-K, General Rules Covering the Loading of Carload Shipments of
Commodities in Closed Cars, or revisions thereof.
9–2
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
DOORWAY PROTECTION
9.8 Key roll strapping, as shown in Figures 9.4 and 9.5, is a method for protecting doors (both
standard and plug type), as well as restricting lengthwise movement in roll paper loads.
STRAP HOLDERS
SHADED AREA
INDICATES ROLLS
TO BE KEY BANDED
A KEY BAND JOINS TWO ROLLS ON
OPPOSITE SIDES OF THE CAR,
PULLED TOGETHER BY TENSIONING
THE STRAP THAT LOCKS THE LOAD
AND TAKES UP LENGTHWISE SPACE
Figure 9.4 Conventional key band doorway protection
A KEY BAND JOINS TWO ROLLS ON
OPPOSITE SIDES OF THE CAR IN A
FIGURE-8 PATTERN
Figure 9.5 Figure-8 key band doorway protection
9.9 Refer to specific loading methods for more detailed application instructions.
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
9–3
DOORWAY PROTECTION
9.10 For plywood and similar panel products in sliding or plug-door cars, use two Type 1A, Grade
4, nonmetallic unitizing straps around the lengthwise stacks in the doorway. See Figure 9.6.
TWO TYPE 1A, GRADE 4
NONMETALLIC UNITIZING STRAPS
Figure 9.6 Doorway protection for sliding or plug-door cars loaded with plywood
9–4
Closed Car Loading Guide—Minimum Loading Standards for Freight in General Purpose Boxcars
CLOSED CAR LOADING STANDARDS
Part
Subject/Title
1 Minimum Loading Standards for
Freight in General Purpose
Boxcars
Publication
Date
1/2014
Formerly
Pamphlet No. 14, Minimum Loading
Standards for Freight in General Purpose
and Specially Equipped Boxcars (12/84)
2 Best Practices for Loading of Roll
Paper
in Railcars
Best Practices for Loading of Roll Paper in
Railcars/Pamphlet No. 39, Supplemental
Loading Standards for Roll
Paper/Pulpboard in Closed Cars (5/11)
3 Minimum Loading Standards for
Plywood and Similar Building
Products in
Closed Cars
Pamphlet No. 8, Minimum Loading
Standards for Sanded and Sheathing
Plywood in Closed Cars (11/85)
4 Minimum Loading Standards for
Lumber in Closed Cars
Pamphlet No. 20, Minimum Loading
Standards for Lumber in Closed Cars
(10/87)
5 Minimum Loading Standards for
Building Brick in Closed Cars
Pamphlet No. 6, Minimum Requirements
for Loading, Bracing and Blocking
Carload Shipments of Building Brick in
Closed Cars (8/83)
6 Minimum Loading Standards for
Prepared Food and Similarly
Packaged Products in Closed
Cars
Pamphlet No. 17, Minimum Loading
Standards for Packaged Food Products in
Closed Cars and TOFC/COFC (10/88)
7 Minimum Loading Standards for
Intermediate Bulk Containers
in Closed Cars
New
8 Minimum Loading Standards for
Bagged and Baled
Commodities in Closed Cars
Pamphlet No. 3, Minimum Loading
Standards for Bagged and Baled
Commodities in Closed Cars (10/93)
9 Minimum Loading Standards for
Coiled Metal Products in Closed
Cars
Pamphlet No. 23, Minimum Standards for
Loading Steel Products in Closed Cars,
Trailers or Containers (4/95)
10 Minimum Loading Standards for
Primary Metal Products in
Closed Cars
Pamphlet No. 37, Minimum Standards for
the Safe Loading of Ingots, Pigs, Anodes,
Rods and Similar High Density Metallic
Commodities in Closed Cars (11/84)
See also:
Intermodal Loading Guide for Products in Closed Trailers and Containers (7/2011)
Open Top Loading Rules Manual, Sections 1–7