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Overhead crane and gantry crane safety in precast factory

01 Aug, 2017

Overhead bridge crane and gantry crane safety in precast factory. Dongqi Crane offers 40 ton gantry crane for precast factory and custom designed crane for various precast factory. Check crane safety for precast factory tip now.

Overhead and Gantry Cranes – OSHA 29 CFR 1910.179.

This standard establishes requirements for inspections, maintenance, lifting and handling loads and other physical crane construction requirements. In essence, an employer who utilizes overhead and/or gantry cranes must make sure there are procedures in place to prevent lifting failures. Such procedures required by the OSHA standard include daily visual operator inspections of the components on a crane. These daily inspections include checking the hoisting ropes, load hooks, limit switches and the hoisting, bridge and trolley brakes.

When checking hoisting ropes, look for obvious defects such as kinks, cuts or unstranding. Make certain the rope is spooling properly on the hoist drum and that the rope is running freely through the running sheaves. Damage to the rope can occur when it is not running through properly.

40 ton gantry crane for precast factory

40 ton gantry crane for precast factory

Load hooks should also be checked for cracks, gouges or bending. A frequent problem with load hooks is damage or employee removal of the safety latch that closes the throat opening of a hook to ensure loads do not accidentally slide off the hook.

Slowly and carefully move the load block to the upper limit switch on the crane in a safe and clear area. If the switch does not work, immediately remove the crane from service. This switch’s function is to prevent raising a load too high and running the load block into the hoist drum. This would cause a failure in the lift, causing a load to fall and putting any employee in the vicinity into grave danger.

An operational check is also required of the braking systems. For instance, lift a load a few inches off the ground to determine if the hoist brake will hold. If any braking mechanism is found to be questionable or not working, immediately remove the crane from service and prevent further use until it is repaired.

Other checks that an operator should perform include observing the crane motions to make sure the crane responds properly to the pendant or remote functions. Make certain the controls are labeled as to function and that they do not stick. If any unusual noises or vibrations are found, this could indicate serious wear or maladjustment and the crane should be taken out of service.

Periodic inspections should be conducted that get more in depth than daily inspections, and in this case must be documented. Dependent on how hard the crane is used and how harsh the environment is, this inspection must be conducted every one to 12 months. Your crane service company or manufacturer can help you determine how frequently these inspections should be conducted. In fact, the crane service company will have the expertise to complete the inspections for you. This type of inspection requires an in-depth knowledge of the equipment and should be conducted only by qualified technicians with the proper training. At a minimum, an inspection utilizing an outside crane service company should be completed annually. Even then, a monthly or quarterly internally documented inspection is recommended.

Operators should be trained in how to control the crane, proper rigging, how to move a load and how to inspect the crane, as well as where the disconnect is located. The crane capacity must be clearly marked on the crane in order for operators to make proper judgments in what can safely be lifted.

Slings – OSHA STANDARD 29 CFR 1910.184. There are many types of slings including chain, wire rope, and synthetic and wire mesh. The most common sling used in the precast industry is the chain. Of course, not all chains are suitable for lifting – be sure to use lifting-grade chains only. As with a crane safety program, an important element in developing a sling program is implementing the proper inspection program.

Due to the repeated use and the harsh environment lifting chains are exposed to, chain links, master links and hooks can wear or become damaged. When a chain fails, it is sudden and without warning. Therefore, OSHA requires a daily visual inspection of slings and all fastenings. In addition, based on conditions and use, a periodic inspection must be performed and documented on all slings. Check chains for excessive wear at all bearing points between links and where the load sits on the hook. If 10 percent of the overall original thickness is worn, the chain must be removed from service.

Check the throat opening for twisting or stretching. If the throat opening has increased by 15 percent over the original opening, the chain must be removed from service. Also look for elongation of the chain and individual links, nicks, gouges, cracks, twisting, deformities and signs of heat damage. An alloy chain must be permanently removed from service if exposed to more than 600 degrees Fahrenheit.

Employee training is another critical component in developing a sling program. All slings must have a rated capacity tag on the chain. This capacity is the maximum amount the chain can lift and is based on a 90 degree angle between the chain and the load. Whenever this angle becomes less than 90 degrees to the load, the capacity of the chain is reduced. No load should be lifted with a chain-to-load angle of less than 30 degrees. Employees should be instructed in the concepts of how load angles affect the chain capacity as well as how to properly attach a chain sling to a load. Train employees in the type of slings that will be used, whether the slings are two-legged, three-legged or quad-type.

Gantry crane for precast factory

Gantry crane for precast factory

Tying it all together

As mentioned earlier, the maximum weight that can be lifted safely is determined by the weakest link within the lift sequence. A failure of any one component, whether a single chain link, a hydraulic line on a forklift or an employee who has made a bad decision, can result in an unsuccessful lift and can cause serious injury to employees as well as damage to product. The NPCA Guide to Plant Safety includes programs that can be adopted and made specific to a precast plant in order to establish a compliant program for both powered industrial trucks and cranes. Other resources include insurance loss control representatives, equipment vendors and service companies.

Overhead crane and gantry crane safety in precast factory for your reference. Dongqi offers types of cranes, inculding overhead crane, gantry crane, jib crane and others for various industiral needs. If you need any hoist or crane, please feel free to contact us. Check Dongqi overhead crane industrial crane services now. 

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