Basic Hoist and Crane

Safety

NOTE: This training does not address OSHA requirements for mobile crane
operations that are involved in construction activities.

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 Introduction

There are many types of overhead cranes at

WHOI:
− Jib Cranes

− Overhead Hoists

− Underhung Hoists

− Some “Home made” systems

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Jib Crane

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Underhung Hoist

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Underhung Hoist

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Overhead Crane

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Underhung Hoist

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 Basic Requirements for Hoists
 All parts must be of adequate strength for rated service.
 Cranes and hoists must have an adequate design
safety factor.
 Each independent hoisting unit shall have brakes.
 The rated load of a crane shall be plainly marked on
each side.
 The rated load of each hoist shall be marked on its load
block.
 All markings must be visible from the floor.

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 Overhead and Gantry Crane Operation

 Hoist operators must inspect equipment daily before

use.
− This operational inspection does not need to be
documented.

 Never operate a crane or hoist if limit switches, steel

ropes, chains or other safety-significant components
are worn or in disrepair.

 Replace nylon or web slings immediately if excessively

worn, damaged, or potentially overloaded.

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 Overhead and Gantry Crane Operation

 Personnel in the direction of

travel should be warned to
move and remain clear of a
lifted load at all times.

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Overhead and Gantry Crane Operation

Pendant Controls
indicate direction of
travel and must be
marked

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Overhead and Gantry Crane Operation

Pendant Controls correspond

with facility markings

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 Overhead and Gantry Crane Operation

 Loads should not be

suspended over personnel
below.

 Under no circumstances
may anyone ride the hook
or load.

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 Overhead and Gantry Crane Operation

 Directional movement
should be made smoothly
and deliberately.

 Avoid rapid movements in

any direction.

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 Overhead and Gantry Crane Operation

 Ensure hook is directly

above load’s Center of
Gravity (CG) for a stable
pick

 Use tag lines to stabilize lift

and control the load

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 Overhead and Gantry Crane Operation

 Do not exceed the rated

load capacity of the crane,
hoist, chain, cable, slings,
or other component.

 When planning a lift, it is

critical to understand and
identify the weakest
component of the crane or
hoist system (this could be
the rigging or part of the
crane/hoist system)

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 Slings, Load Chains, Other Lifting
Devices
 Slings, load chains and
other lifting devices must be
fully and securely seated in
the hook before moving a
load.

 Remove slack from the

sling, chain, or cable before
lifting a load.

 Avoid shock loading

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Avoid Swinging Loads

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 Practices to Avoid Swinging Loads

Use the following practices to avoid swinging loads:

− Before lifting, locate the hook and rigging

connection directly above the Center of Gravity of
the load.

− Ensure hoisting ropes are vertical. Do not pull or

push the load.

− Maintain two full wraps of cable on the hoisting

drum.

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 Overhead and Gantry Crane Operation

 When lifting loads at or near capacity, test the hoist

brakes by returning the master switch or push button to
the “OFF” position after raising the load a few inches off
the floor.

 If the brakes do not hold, lower the load to the floor

slowly and do not operate the crane. Report the
situation immediately to the Facilities Department and
DO NOT USE until repaired.

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 Overhead and Gantry Crane Operation

 Ensure that all loads are lifted high enough to clear

obstructions before moving the bridge or trolley.

 Whenever possible, maintain a minimum clearance of

one foot above loads and to the sides. Raise the load
only to the height necessary to clear lower objects.

 Never pull a hoist by the pendant cable.

 Hard hats are required if the hook is raised above your

head.

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 Overhead and Gantry Crane Operation

 Never leave the controls unattended while a load is

suspended. If it becomes necessary to leave the
controls, lower the load to the floor or stable surface.

 Familiarize yourself with the location of the disconnect

switch.

 If loss of electrical power occurs, place controls in the

“OFF” position to prevent unexpected startup upon
restoration of power. Consider blocking or isolating.

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 Overhead and Gantry Crane Operation

 Disconnect power to a hoist that is unsafe or in need of

repair. Arrange to have the disconnect switch locked
and the control panel tagged with and “Out of Order” or
“Do Not Operate” tag.

 Never operate a hoist that has been tagged with an

“Out of Order” or “Do Not Operate” tag, or is your
opinion, UNSAFE TO OPERATE.

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 Overhead and Gantry Crane Operation

 At end of operation – place hook and pendant out of the

way so as not to be an obstruction

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 HOISTS/CRANES
Daily Inspection Checklist
 Check for any loose or missing parts.

 Check end stops. End stops prevent the trolley from

running off the beam.

 Know the location of disconnect switch that will cut the

power to the hoist or crane. Be sure it is readily
accessible and not blocked.

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 HOISTS/CRANES
Daily Inspection Checklist
 Make sure all control buttons are labeled to indicate
their function. Operate each button to make sure it
functions properly, releases immediately, and does not
stick.

 Check upper hoist limit switch by slowly raising the

block to trip the switch.
N

W E

S
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 HOISTS/CRANES
Daily Inspection Checklist
 Operate the crane or hoist several feet in each direction
that it travels. Listen for any unusual noises. Look for
any jerky movements.

 When moving an A frame hoist, take care to ensure that

the wheels on each side stay on the track.

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 HOISTS/CRANES
Daily Inspection Checklist
 Check all hooks. Hooks should not be cracked,
stretched, bent, or twisted. Each hook must have a
safety latch that automatically closes the throat of the
hook.

 If the latch is bent, spring is broken, or is otherwise

damaged the latch must be repaired before use. Hooks
should rotate freely in block assembly without any
“grinding” felt or heard.

 Report problems to Facilities Department and tag out of

service.

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 HOISTS/CRANES
Daily Inspection Checklist
 Check the block assembly for structural damage or
cracks in any components.

 Sheaves should rotate freely without any grinding.

 The sheave guard must be unbroken and intact. No

part of the sheave guard should be in contact with the
wire rope or sheave.

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 HOISTS/CRANES
Daily Inspection Checklist
 Check the wire rope by lowering the block to the lowest
level and looking for the following conditions. If any of
these conditions are observed, they should be reported
immediately and tagged out of service.

 Kinked, crushed, cut, or “bird caged” wiring, or wiring

with heat damage.

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 HOISTS/CRANES
Daily Inspection Checklist
 Check load chain for damage, wear at contact points,
cracks, or distorted (bent, twisted, or stretched) links.

 Inspect all mechanical coupling links to insure linking

pins are secure and in good condition. Report unsafe
conditions immediately and tag out of service.

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 HOISTS/CRANES
Annual Inspection and Maintenance
 Facilities is responsible for annual inspection, proof
tests and preventive maintenance

 If there is a problem with the hoist/crane, notify

Facilities

 DO NOT OPERATE DEFECTIVE OR OTHERWISE

UNSAFE CRANES OR HOISTING DEVICES
– TAG OUT OF SERVICE

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 Synthetic Slings

 Strong and dependable

 Suitable smooth surfaces

 Relatively easy to cut, little resistance to abrasion,

chemicals, UV

 ASTM B783-1990 Breaking strength 5X rated capacity

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 Synthetic Slings

 Must be labeled with:

− Manufacturer ID

− Code Number

− Rated Load Capacity for 3 common hitches

− Nylon, polyester, and other synthetic materials

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 Synthetic Slings
Initial Inspection
 New and Repaired slings

− Obtained from approved source with proper

engineering design

− Correct type and rated capacity marked on sling

− Not damaged in shipment/handling

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 Synthetic Slings
Inspections
 Sling shall be inspected each time that it is used

 Annual inspection by designated personnel experienced

in the inspection of slings

 Look for:
− Excessive abrasive wear
− Cuts, tears, punctures, crushed fabric
− Burns, charring, chemical damage
− Knots that cause doubt about safety

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“Inspect before each use and discard when red striped
core yarns appear. Do not exceed rated capacity”

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 Synthetic Slings

 Capacity ratings must be legible on the manufacturer’s

label. The capacity of the sling being used must be
adequate for the load and attachment (sling hitching)
method.

 Replace slings immediately if excessive wear occurs.

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 Synthetic Slings
Storage
 Slings should be hung up in a designated location, cool,
dry and away from exposure to UV, sunlight, and non-
compatible chemicals

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We Like This!

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 Analyzing and Rigging the Load

 The following steps must be taken before performing a

lift:

− Determine the total weight of the load and the WLL

of the crane/hoist

− Decide how the load will be connected to the lifting

hook and how the sling will grip the load

− Determine sling capacity required

• Calculate the loads for the angles and

attachments

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 Determining the Weight

“ The most important step in any

hoisting operation is to
determine the weight of the
load. Only after this
determination is made, can
proper rigging equipment be
selected.”

NOTE: Contact EH&S to obtain a copy of Bob’s Rigging and Crane Handbook

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 Determining the Weight

 Sources of weight determinations

 Documents, manuals, engineering designs

− Information on the name plate, shipping tag, painted

on the load

− Weighing the load – weight scales, crane load

indicating system

− Calculating the Weight

 See Bob’s!

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 Determining the Weight

See Bob’s

Height
Width

WEIGHT = length x width x height x unit weight

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 Determining the Weight

 Examples from Bob’s

− Cone shapes
− Pyramids
− Wedge
− Etc.

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 Center of Gravity

 On initial pick – the load tilts - mark

load
 Select two slings of different
lengths to tilt load in the opposite
direction
 After center of gravity is
determined, position hook directly
above

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 Calculating Sling Loads

1000 lbs

1000 lbs

1000 lbs
Vertical load
500 lbs

500 lbs

600 450 300

1000 LBS 1000 LBS 1000 LBS 1000 LBS

Load on sling = vertical load divided by the sin of angle

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 Calculating Sling Loads

Vertical load = 500 lbs for each sling

 60 degrees
 1/sin (60) = 1/0.866 = 1.15 x 500 = 577 lbs

 45 degrees
 1/ sin (45) = 1/0.707 = 1.414 x 500 = 707 lbs

 30 degrees
 1/ sin (30) = 1/0.500 = 2.00 x 500 = 1,000 lbs

Also can use “load angle factor” from Bob’s

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 Calculating Sling Loads

 What would the load on each sling be if the angle were

10 degrees?

 If it were 5 degrees?

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 Calculating Sling Loads

 Vertical load = 500 lbs for each sling

For 10 degrees
Sin 10 degrees = 0.174
 1/0.174 = 5.75 x 500 = 2,879 lbs

For 5 degrees
 Sin 5 degrees = 0.087
 1/0.087 = 11.47 x 500 = 5,736 lbs
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 Rules of Thumb

 Never rig below 30 degrees

− 30 degrees doubles the tension

 45 or higher is preferred

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 Rigging Hardware

 Forged Eye Bolts

− Never use regular eye
bolts for angular lifts
450
− Always use shoulder
type eye bolt for
angular lifts 900
Direction of Pull Adjusted
Working Load
Limit (WLL)
45 Degrees 30% of WLL
90 Degrees 25% of WLL
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 Example Problem

 Lift is a rectangular container full of sea water measuring

3 feet by 3 feet by 2 feet (3x3x2)

 4 sling legs

 Sling angle of 45 degrees

 Questions:
− Determine the weight of the load?

− Select the appropriate sling?

− What type and size eye bolts should be used?

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 Example Problem - Information

 Average density of sea water * – 64 lbs/ft3

 Sin (45) = 0.707

− also see Bob’s for load angle factors

 Rigging Hardware factors – see Bobs

* Verify density with knowledgeable person

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 Answers

 L x W x H x Density
− 3 x 3 x 2 x 64 = Weight = 1,152 lbs
 Vertical load for each sling (one sling is balancing)
− 1,152 divided by 3 legs = 384 lbs
 Tension in each sling leg
− 1/ sin (45) = 1/0.707 = 1.414 x 384 = 543 lbs
 Eye Bolt (from table)
− ½” is the best choice; 0.3 x 2,200 = 660 lbs
− 3/8” is too small; 0.3 x 1,200 = 360 lbs
− Always use a shoulder type eye bolt for angular lifts

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 1,152 lbs

384 lbs

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 To receive credit for this training access the following link
Hoist and Crane Safety Quiz and complete the quiz
 Passing grade is 80%
 Quiz results will automatically be forwarded to EH&S
 You can retake the quiz if you fail
 For questions contact EH&S at ext. 3347 or
gcrowley@whoi.edu

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