Servicing issues

BRAKES Maintaining the roadgoing elements of the crane is just as important as the superstructure.
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In addition, all wire ropes, including stationary supports or attachment points, help determine lifting capacity and are part of the overall structural integrity of a crane’s lifting capacity.

The following elements may also affect structural integrity and these are the load chart capacity in relationship to stability and the boom angle limitations which affect stability and maximum capacity.

Additionally, the knowledge of the length of boom and radius in determining capacity.

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Stability failures are foreseeable, but in structural failure it is almost impossible to predict what component will fail at any given time. No matter what the cause, if the crane is overloaded, structural failure can occur.

As stated above, cranes are carefully designed, tested, and manufactured for safe operations. When used properly they can provide safe reliable service to lift or move loads.

Because cranes have the ability to lift heavy loads to great heights, they also have an increased potential for catastrophic accidents if safe. operating practices are not followed.

Planning
Accidents can be avoided by careful job planning. The person in charge must have a clear understanding of the work to be performed and consider all potential dangers at the job site. A safety plan must be developed for the job and must be explained to all personnel involved in the lift.

Before operations begin for the day, a walk around inspection needs to be conducted to ensure that the machine is in proper working condition. Only qualified and properly designated people shall operate the crane.

Regular inspections are important, they provide a means of detecting potential hazards or conditions that could contribute to a sequence of events leading to an accident.

Safe, reliable, and the economic operation of lifting equipment, cannot be ensured without regular safety inspections and thorough preventive maintenance programs.

A thorough inspection program can forecast maintenance needs or potential equipment failures or malfunctions.

The lack of such a program could result in serious deterioration of the equipment which might lead to excessive replacement, or repair charges, as well as an increased potential for accidents.

Mobile crane maintenance checklist (as recommended by OSHA)

1. Check that all exposed moving parts are guarded. A removed guard may indicate that a mechanic is still working on part of the crane. 
2. Visually inspect each component of the crane used in lifting, swinging, or lowering the load or boom for any defects that might result in unsafe operation. 
3. Inspect all wire rope (including standing ropes), sheaves, drums rigging, hardware, and attachments. Remember, any hook that is deformed or cracked must be removed from service. Hooks with cracks, excessive throat openings of 15%, or hook twists of 10 degrees or more, must be removed from service. 
4. Check for freedom of rotation of all swivels. 
5. Visually inspect the boom and jib for straightness and any evidence of physical damage, such as cracking, bending, or any other deformation of the welds. Look for corrosion under any attachments that are connected to the chords and lacing. Watch carefully for cracking or flaking of paint. This may indicate fatigue of the metal which often precedes a failure. On lattice booms, look for bent lacing. If they are kinked or bent, the main chord can lose substantial support in that area. When lacing is bent, the ends also tend to draw together which pulls the main chords out of shape. This precaution is especially important on tubular booms where every component must be straight and free from any dents.
6. Do not attempt to straighten these members by hammering or heating them and drawing them out. They must be cut out and replaced with lacing to the manufacturer’s specifications, procedures, and approval. 
7. Inspect tires for cuts, tears, breaks, and proper inflation. 
8. Visually inspect the crane for fluid leaks, both air and hydraulic. 
9. Visually check that the crane is properly lubricated. The fuel, lubricating oil, coolant and hydraulic oil reservoirs should be filled to proper levels. 
10. Check that the crane is equipped with a fully charged fire extinguisher and that the operator knows how to use it. 
11. Check all functional operating mechanisms such as: sheaves, drums, brakes, locking mechanisms, hooks, the boom, jib, hook rollers brackets, outrigger components, limit switches, safety devices, hydraulic cylinders, instruments, and lights.