Line A pt 2. Flashcards
What are hydraulic jacks used for apposed to being used for lifting great heights?
They are used for lifting heavy loads mainly.
How many pistons are in hydraulic jacks?
Two:
A smaller pumping piston
A larger lifting piston.
What is the relation of the small pump piston and large lifting piston in a hydraulic jack?
The small pump piston forces oil against the larger lifting piston.
How is the mechanical advance determined in a hydraulic jack?
The mechanical advance is determined by the ratio of the small pump piston and larger lifting piston.
For some hydraulic jacks, how can the total length of the jack be adjusted?
By using an adjustable screw head.
How do some hydraulic jacks open and close the valves at the base of the body?
Using an adjustable handle made from short length steel tubing and a pair of notches at the end.
How do you lift a load with a hydraulic jack?
Close the valve on the jack, insert the handle into the pump, and move the handle up and down.
How do you lower a load supported by a hydraulic jack?
Turn the handle at the base of the jack counter clockwise.
Why should the valve be opened slowly when a hydraulic jack is supporting a load?
By opening the valve slowly the supported load is lowered slowly.
When should one rely on a hydraulic jack to hold a load for an extended amount of time.
Never. Due to an often small internal leakage of fluid, the load will eventually and gradually creep down.
When does the capacity of a mobile crane decrease?
When you extend or lower the boom.
The boom is the arm of the crane.
Can a load be pulled sideways by a crane?
No. Always position the hook of a crane directly above the load.
When should a safety check of a mobile crane be done?
Prior to operating the machine.
At what centered measurement is the capacity of a lift truck usually determined?
At 24” from the heel of the forks.
Where should the capacity of a lift truck be displayed?
On a name plate attached to the machine.
How many pulleys can be grouped together to form a block?
Two or more pulleys.
Pulleys are grouped together in housings or frames, creating what is known as what?
A block.
What is a tackle?
A tackle is the rope or cable that is threaded through the blocks.
Describe a fixed block.
This block does not move and is anchored to a secure point, such as a ceiling, a beam, or a wall.
Describe a travelling block.
This block is attached to the load. As the rope is pulled, this block moves along with the load.
Why is it important to know the lifting capacity of a load?
Because the load to be lifted could possibly be higher than the breaking strength of the rope.
How can the increased lifting capacity of a manual lifting device be calculated?
By counting the number of rope segments coming out of the travelling block.
For example, if the travelling block has 4 rope segments coming out of it and is supporting the load, the mechanical advantage (MA) is 4. This means the input force required to lift the load is reduced by a factor of 4. If you need to lift a 400-pound load, you would only need to exert a force of 100 pounds.
What kind of braking and safety system does a block and tackle have?
None.
A block and tackle cannot support a load until the lifting device is _______.
Anchored.
What forms can communication and signaling for crane operations incude?
Sound, light, hand, and arm, thumb, and finger positioning.
What regulating authority controls the use of types and hand signals?
OHS
Occupational Health and Safety
How many ways can one signal using light or sound?
Four different ways.
Stupid Rabbits Love Apples
How do you signal Stop using light or sound?
1 horn/bell or flash.
How do you signal Raise using light or sound?
2 horn/bell or flash
How do you signal Lower using light or sound?
3 horn/bell or flash
How do you signal All Clear using light or sound?
4 horn/bell or flash
What does the signal “all clear” indicate?
This sign indicates to the operator the hoist is complete and it is safe to operate again.
How do you signal up or hoist using hand signals
Point your finger up and move it in small circles.
How do you signal lower using hand signals
Same as up, but point your finger down and move in small circles.
How do you signal stop using both hands
Stretch both arms out on both sides with palms towards the ground and three fingers out. You should be posed like a T.
How do you signal stop using one hand
Position palm towards operator and wave hand side to side.
How do you signal bridge travel using hand signals
Extent both arms and face palms in direction of travel. Making a pushing motion.
How do you signal trolley travel using hand signals
Point using your thumb in a jerk motion in the direction of travel..
How do you signal raise or lower of a boom using hand signals
Pointing your thumb in direction (raise or lower)
How do you signal to lengthen or shorten the boom using hand signals
Point with both thumbs inwards (for shorten) or outwards (to extend)
How do you signal to swing the boom using hand signals
Point in the direction of required swinging with arm extended.
How do you signal to lower or raise the boom while lowering the load with a single hand
Point thumb in direction of travel (raise or lowering of the boom) and move fingers in and out in a grasping motion.
How do you signal to use the main line?
Tap fist to head, then use regular signals to further direct.
How do you signal to use whip line?
Tap hand to elbow, or point to shoulder, then use regular signals to further direct.
How do you signal slow movement using hand signals?
Placing palm on top of hand signals.
How do you signal to dog everything?
Clasp both hands in a handshake manner Infront of your body.
What are tag lines?
Tag lines are ropes or lines attached to a load or object being lifted or moved. These lines are used to control or stabilize the load’s movement, especially in situations where precision or safety is critical.
How many legs are needed to support a load prone to tipping and rolling?
Three, preferably four.
What is a sign of unbalanced weight?
When one end of the load lifts before the others.
What direction should you move a load by hand?
Away from you in a pushing motion.
What is prevented when one moves a load by hand in a pushing motion rather than a pulling?
Entrapment. This is when the sling supporting the item in broken and the worker pulling said load gets crushed by the fallen load. Pulling may also cause back strain.
Describe a bend in a rope.
A bend is a knot that joints two separate ropes together.
Describe a hitch in a rope.
A hitch attaches a rope to an object such as a rail, post, or ring.
Describe a knot in a rope.
A knot secures the two ends of the same rope, such as a shoelace.
What is the loop of the rope called?
The bight.
What is the long part of the rope called?
Standing part.
What is the end of a rope called?
The end. Trick question.
What is a disadvantage of knotting a rope?
Knotting reduces the ropes strength due to the knot creating uneven stresses.
What are welded lugs?
A welded lug refers to a small metal component that is welded onto a larger structure or object. Lugs are typically used as attachment points or connection points for other equipment, devices, or parts. They can be permanent or temporary.
How do you find the suitable dimension for a welded lug?
Be sure of the grade and thickness and refer to the welded lug chart.
Who can install a welded lug?
A qualified welder.
As the sling angle increases the strain on the lug _____
Also increases.
What are some benefits synthetic slings posses compared to chains?
They don’t damage painted or polished surfaces.
They are also non-sparking so there is much less of risk for current travelling through them and damaging lifting machinery.
What are some disadvantages synthetic slings posses compared to chains?
They are damaged easily by sharp or pointed surfaces.
What does it mean to see red in a synthetic sling?
The sling has worn and should be put out for service.
How do you dispose of a sling?
Cut the sling to prevent other from using it and take out of service.
How can you protect a synthetic sling when using it on a load with sharp edges?
Using a A sling protector is a slap or strip of material placed between the load and sling to protect the sling from being damaged.
What is a quick and convenient method of fabricating a wire rope sling on site?
Using a wire rope clip.
What is the most widely used and common type of wire rope clip?
The U-bolt type.
What is the least used and most expensive type of wire rope clip?
The double saddle type.
What saying is important to remember what end of the rope is to be saddled with a wire rope clip?
“Never saddle a dead horse” meaning to always saddle the live end of the rope rather than the dead end.
How do you determine how many clips are needed for a rope?
Based on the diameter of the rope. (And reading the OHS regulation table).
ie. 2 1/4” dia. rope = 8 clips with 14” between each one.
What are eye bolts?
Eye bolts are solid rounds combined with a threaded shank and is used as a point of attachment. They are mainly used for rigging and lifting machinery.
What are eye bolts made of?
Forged alloyed steel.
How many types of eye bolts are there?
Two. Shoulder and shoulderless.
What type of eye bolt cannot be used to hoist overhead.
Shoulderless eye bolts.
Can eye bolts be fabricated?
Yes but they must be proof tested prior to using.
What is eye bolt lifting capacity based on?
Bolt diameter
Bolt length
Thread depth
Material
Lifting angle.
Shouldered eye bolts can withstand pulls up to what degree from a vertical position.
45 degrees.
A shouldered eye bolt can withstand pulls up to 45 degrees from vertical provided the pull is what?
Provided the pull is applied along the plane of the eye.
If there is a tiny gap between the shoulder and the load, is it still okay to use for hoisting overhead?
No. Even a tiny gap will act as a shoulderless eye bolt and could break off under stress.
What does a chain hoist do?
A chain hoist is a mechanical device used for lifting and lowering heavy loads using a chain.
Does a chain hoist connect directly to the load?
No. The chain hoist will need to be attached to a sling or rigging to provide a point of attachment.
When should you test the proper direction of hook travel?
After repairs and overhauls.
What percentage can a choker hitch carry when straight pulling?
75% of its rater work load limit.
How many types of bracket hitches are there?
Three.
Single, double, and double-wrap.
They look like their names.
In a single basket hitch, when the hitch legs are in the vertical position, what percentage of the working load limit can the hitch safely lift?
200%
What types of loads do you use a single basket hitch for?
Only use on loads that will not tilt and/or slide.
What degree should the legs of a double backet hitch be at least to the horizontal the legs from sliding towards one another?
60 degree incline at least.
What is a benefit of using longer slings for a double basket hitch?
The use of longer slings allow the legs to be further apart while still maintaining a 60 degree incline.
What is the purpose of a double wrap basket hitch?
The extra wrap around compresses the load and prevents even the top pieces from sliding off and out.
What is the formula to calculate the weight of a W8 x 18 wide flange beam (imperial dimensions)?
W8 x 18 = 8” tall x 18lbs/foot
What is the formula to calculate the weight of a W200 x 27 wide flange beam (metric dimensions)?
W200 x 27 = 200mm tall x 27kg/metre
What is the formula to calculate the weight of a C8 x 11.5 standard channel (imperial dimensions)?
C8 x 11.5 = 8” wide x 11.5lbs/foot
What is the formula to calculate the weight of a C200 x 17 standard channel (metric dimensions)?
C200 x 17 = 200mm wide x 17kg/metre
What types of lanyards can be used for personal fall protection?
Only manufactured lanyards should be used.
At what height is fall protection needed?
When working over 3m (10ft) or more above a lower level.
What are the four critical parts of fall protection?
Fall restrain systems - intended to prevent worker from falling over edges
Fall arrest systems - intended to stop the worker from hitting an object if they fall
Harnesses and restrains - the PPE worn while using a system
Lifelines and Anchoring - the connection between the worker and the structure they are working on
