Knot

Transcription

Knot
Knot
Guide
A program based on the RESET
General Rescue curriculum
Terms
• Knot: A fastening made by tying together
lengths of rope or webbing in a prescribed way
• Bend: A type of knot that is used to join two
ends of rope, accessory cord, or webbing
• Hitch: A type of knot that can only be tied
around an object. If the object is removed, the
knot will collapse
Purpose of Knots
• The different purposes for knots are:
– Attach a rope to an object
– Create an end of the line loop
– Create a mid-line loop on a rope
– Join two ropes, accessory cords, or webbing
ends
– Grip another rope
– Create a safety mechanism
– Create a friction device
Knot’s Effect of Rope
• Knots reduce the
strength of rope by
approximately 30%
Strands are stretched and
carry the attached load
– This is important when
determining safety
factors
– The overall strength of a
system will depend on
the weakest component
of the system
Strands are
compressed
and are not
under load
When are you done typing a knot?
When it is DRESSED and SET
– All knots tied on rope and webbing
will have 4-6 inches of tail after the
knot (including safeties if the knot
requires them)
• Tails are needed – as the knot loads it
cinches up and shortens the tails
– All knots tied in accessory cord will
have a tail equal to 2-4 times the
diameter of the rope
• Example: 8mm cord = ½” to 1½” of tail
1-2 hand
widths of tail
(1 preferred)
Accessory
cord is 8mm
and smaller
List of Knots
•
•
•
•
•
•
Overhand
Square Knot w/Safety
Figure 8 Stopper
Figure 8 on a Bight
Double Loop Figure 8
Figure 8 Follow
Though
• Figure 8 Bend
• Bowline w/Safety
•
•
•
•
•
•
Butterfly
Münter Hitch
Clove Hitch w/Safety
Water Knot
Double Fisherman’s Bend
Triple Wrapped Prusik
Hitch
• Trucker’s Hitch
(for patient packaging)
Overhand Knot
Type: Knot
Purpose: Create a
safety mechanism
Usage: Securing the tail
end of a knot to
prevent knot slippage
Square Knot
with Safeties
Type: Knot
Purpose: Join two ends
of rope (of equal
diameter)
Uses: Secure ends of
rope on the Sked
device
Figure 8 Stopper
Type: Knot
Purpose: Create a
safety mechanism
Uses: To prevent the
end of a rope from
passing through a
system
Figure 8 on a Bight
Type: Knot
Purpose: End of a line
loop
Uses: Create an
attachment point at
the end of a rope
Loop size depends on
application
Double Loop Figure 8
on a Bight
Type: Knot
Purpose: End of line loop
Uses:
• Create an attachment
point at the end of a line
• Differentiate between two
ropes of the same color
• Create a multi-point
anchor
• Construct a hasty
harness
Figure 8 Follow Through
Type: Knot
Purpose: Attach a rope
to an object
Uses: Build an anchor
or litter attachment
Figure 8 Bend
Type: Bend
Purpose: Join two ends
of rope
Uses: Connect two
ropes of similar size
(for life safety – ropes
should be same size)
Bowline w/Safeties
Type: Knot
Purpose: Attach a rope to
an object
Uses: Build an anchor or
litter attachment
The bowline was said to reduce
rope strength by 50%, but this
was with natural fiber rope.
Synthetic rope with a bowline
strength loss is similar to other
knots.
Butterfly Knot
Type: Knot
Purpose: Create a midline loop
Uses: Creates an
attachment point in
rope that can be
pulled in any direction
Münter Hitch
Type: Hitch
Purpose: Create a
friction device
Uses: Used to
control a lowering
system or function
as a capture or top
belay
Clove Hitch w/Safety
Type: Hitch
Purpose: Attach a rope
to an object
Uses: Litter attachment
or patient packaging
Water Knot
Type: Bend
Purpose: Connect
two ends of
webbing
Uses: Create a loop
in webbing to build
an anchor
Double Fisherman’s Bend
Type: Bend
Purpose: Join two
ends of
accessory cord
Uses: Building a
Prusik Loop
Triple Wrap Prusik Hitch
Type: Hitch
Knot should be
positioned to the
side of the loop
Purpose: Grip a rope
Uses:
• Create a rope grab
• Litter attachment
• Progress capture
• Top belay
• Quick attachment point
for SRT
This animation only shows two wraps
Trucker’s Hitch
Type: Hitch
Purpose: Attach a rope
to an object
Uses: Secure lashing
during patient
packaging or create a
multi-point anchor.
Also used to tension a
line