official study guide Rigging Flashcards
CFR 1926.251 Subpart H
rigging equipment
Between the trolley hook and the load is ___.
rigging
What are some examples of rigging?
- Chains
- Wire rope
- Natural rope
- Synthetic webbing
1926.251 General
- Rigging inspected prior to shift(s)
- As necessary during use
- Removed if defective
- Remove rigging equipment when not in use
1926.251 Scope
- Covers slings and hoisting material handling equipment
- Alloy steel chain,
- Wire rope,
- Metal mesh,
- Natural or synthetic fiber rope (conventional three strand construction), and
- Synthetic web (nylon, polyester, and polypropylene).
1926.251(a)
Rigging equipment for material handling. Synthetic fiber, metal mesh, wire rope, alloyed steel.
◦ Grade 28
General Utility Chain
◦ Grade 43
High Test Chain
◦ Grade 70
Binding Chain
◦ Grade 80 Alloy Steel Chain:
The only one used for
overhead lifting!
Check for wear, gouges, stretch, ____.
shearing
Chain inspection is ___.
LINK by LINK
____ link extremely unsafe. Use with grab hooks.
Twisted
Tags: should be on every chain:
Size, Grade,
Capacity
1926.251(b)
Alloy Steel Chain
When using wire ropes, Follow manufacturers_____ recommendations,or Tables H - 3 through H - 14
safe
working load
When using wire ropes no __ in wire
rope except where
permitted in (c)(3) &
(c)(4)(ii)
knots
A typical wire rope may be
designated __ FW PRF
RLL XIP IWRC.
6X25
What does this mean? 6X25 FW PRF RLL XIP IWRC
A 6 strand (6X25) of filler wire construction (FW).The grade of wire used is
Extra Improved Plow Steel
(XIP). The strands are preformed (PRF) in helical pattern before being laid Right Lang (RLL) around an Independent Wire Rope Core (IWRC).
1926.251(c) Wire Rope
End strands covered or blunted
What are the four types of slings?
- Choker
- Basket
- Straight
- Bridle
When using a mechanical splice, what is illegal?
A pigtail!!!
1926.251(c) Wire Rope
Wire rope shall not be used if, in any length of eight diameters, the total number of visible broken wires exceeds 10 percent of the total number of wires, or if the rope shows other signs of excessive wear,corrosion, or defect.
When using a Hand Tucked Eye Splice ___ is illegal.
blunted strands
When using wire ropes U-bolt applied so that the "U" section is in contact with the \_\_\_of the rope.
dead end
When dealing with wire ropes use Table H - 20
to determine
number and ___
of clips.
spacing
When dealing with wire ropes, never ____
slings with knots or
bolts.
shorten
When using wire ropes, protect slings from
_____.
sharp edges
When using wire ropes never apply a ____ when
lifting.
shock load
When using wire rope never place __
between sling &
load when
tightening
finger
1926.251(d)
Natural & Synthetic Rope
When using natural nd synthetic ropes, what tables apply?
Tables H - 15 through H - 18 apply
When using natural and synthetic topes,___used instead of splices
knots
1926.251(e)
Synthetic Webbing
(nylon,
polyester, and
polypropylene).
Synthetic
webbing
(1)Each synthetic web
sling marked or coded to
show:
◦ (i) Name or trademark of manufacturer. ◦ (ii) Rated capacities for the type of hitch. ◦ (iii) Type of material.
1926.251(e) Synthetic Webbing should not be used ____.
Don’t use around
acids or phenolics.
1926.251 (f)
Shackles and hooks.
What table is shackles and hooks?
H-19
How should you test shackles and hooks?
Tested to twice the intended safe working
load before they are initially put into use.
Maintain a record of the dates and results
of such tests.
___ are used for lifting,
towing, pulling and
securing.
Hooks
Two general classifications for hooks:
sling hooks, Grab hooks
to which load
or force is applied to the
base (bowl saddle)
Sling Hooks:
contain a throat or slot of uniform width for securing on the link of a chain, usually to form a chain loop for securing the load
◦ Grab Hooks:
When using hooks do not exceed the working ___.
load limit
Only use alloy heat treated hooks for____.
over-head lifting
Do not or use the hook in any manner for which it was not intended.
tip load
When using hooks do not shock load or ___.
dynamic load
Never apply load to ___, latches are only to retain slack chains and slings
hook latches
Hook inspections
Wear
Deformation
Cracks
Sharp Nicks
Only___are designed for tip loading.
foundry hooks
Balanced
100%
1/4 off center
86%
Point loading
40%
1/2 off center
80%
3/4 off center
70%
When using hooks avoid:
•Side load •Back load •Tip load
What is the max twist for a hook?
10 degrees
Hoist load chains do
not stretch __.
(they wear)
Sling chains chain stretch ___.
10 - 15 %
Grades are indicated ____.
on side of link
Whenever wear at any point of any chain link exceeds that shown in Table H-2, the assembly shall be removed
from service.
1926.251(b)(5)
when dealing with chains ___ can reduce
link cross-section.
Corrosion
Link by link inspection is
facilitated by ____ the
chain.
collapsing
Wear occurs in areas of
high rubbing, what are these two areas?
- The bearing points of
interlink contact. - Outside of straight
side barrels.
The load on quadruple branch slings seldom have the load evenly distributed among the four branches. For this reason \_\_\_\_\_\_\_\_ set the load limit for quad branch slings to the equivalent rating for a triple branch sling of the same type.
sling charts for quad branch
slings
Ropes and chains shall be regularly _____.
lubricated
Wire rope wear is based on:
- Loading
- Bending (# of times)
- # of use cycles
Change in rope diameter is criteria for ___.
retirement.
The area in a wire rope to check wear is where it travels over the___ in
the section from picking a load to lifting it.
block
Wire tends to wear flat on outer
strands, especially where it travels _____.
over drums & sheaves.
Check for wear in clevis:
In the bowl of the saddle
•Check the pin for:
- Straightness
* Wear
Check for distortion in the:
•Open end of the ‘U’
- Spreader beams can be used with a ____ to handle long loads.
- Reduces load tipping
- Each leg will carry one-half the total load
double vertical hitch
•Spreader beams must be manufactured for that purpose and have a ____ indicated.
rated capacity
A load is stable when:
◦ The hook is directly above the center of
gravity of the load
Estimate the center of gravity:
- Lift the load just enough to clear the
ground - If the hook is not over the center of gravity
the hook will travel to the center of gravity
If the load tips more than ___ , the rigging should be adjusted.
3°
The longer the ____ , the more stable the load will be.
sling legs
Four grades of chains:
- Grade 28-General utility chain
- Grade 43-high test chain
- Grade 70-Binding chain
- Grade 80-Alloy Steel chain
Alloyed steel chain rules: CP Inspections made and based on.
- Frequency of sling use
- Severity of service conditions
- Nature of lifts being made
- Experience gained on the service life of slings used in similar circumstances.
Six Wire rope rules:
- U-bolt applied so that the “U” section is in contact with the dead end of rope.
- Use table H-20 to determine number and spacing of clips.
- Never shorten slings with knots or bolts
- Protect slings from sharp edges
- Never apply a shock load when lifting
- Never place finger between sling and load when tightening.
Removed natural synthetic rope from service if:
- Abnormal wear
- Powdered fiber between strands
- Broken or cut fibers
- Discolored or rotting
remove synthetic webbing from service if:
- Acid or caustic burns
- Melting or charring of any part of the sling surface
- Snags, punctures, tears or cuts;
- Broken or worn stitches
- distortion of fittings.
Rules for Rigging Safety
- Know the weight of the load
- Know the center of gravity of the load.
- Make load attachment above the center of gravity of the load.
- Select hitch that will hold and control.
- Know the rated capacity of slings and hardware.
- Select sling best suited for load.
- Inspect all rigging before the lift.
- Protect sling from sharp surfaces.
- Proper calculation of increased tension caused by sling angles (on all rigging components!).
- Calculate reductions when using choker hitch.
- Keep personnel clear from lift area.
- Lift load a few inches then check rigging.
- Know limitations of all lifting devices used.
- Lift slowly and stop slowly.
Hook/Load Angles
A. Balanced 100% B. 1/4 off center 86% C. 1/2 off center 80% D. 3/4 off center 70% E. Point loading 40%