Crane presentation

CRANE :- A large machine used for moving heavy objects by suspending them from a projecting arm or beam

Overhead crane

Overhead crane being used in typical machine shop. The hoist is operated via a wired pushbutton station to move system and the load in any directionMain article: Overhead craneAn overhead crane, also known as a bridge crane, is a type of crane where the hook-and-line mechanism runs along a horizontal beam that itself runs along two widely separated rails. Often it is in a long factory building and runs along rails along the building's two long walls. It is similar to a gantry crane. Overhead cranes typically consist of either a single beam or a double beam construction. These can be built using typical steel beams or a more complex box girder type.

Mobile crane:-

Mobile craneThe most basic type of mobile crane consists of a truss or telescopic boom mounted on a mobile platform — be it on road, rail or water. Common terminology is conventional and hydraulic cranes respectively.

Truck-mounted crane :-

Developed truck-mounted crane at workTruck-mounted craneA crane mounted on a truck carrier provides the mobility for this type of crane.

TOWER  CRANE :-

A tower crane is a piece of equipment used to move or transport oversized objects. It is a stationary device, which means the base of the crane does move. A large, fixed towersupports a horizontal beam, or jib, which sits atop the tower to form an uneven letter “T.” A tower crane is often used in the construction industry to set steel beamsand other large building components. It may also be used in the shipping or transportation industry to load and unload large freighters.

DUTIES WHILE WORKING ON THE CRANE : -
1.While working on the crane the operator should see that proper lighting is ensured.
2.Before leaving the crane cabin for any purpose the operator must bring all the controllers to the neutral position cut -off the switch in the cabin.
3.Mobile cranes should be parked on hard soil or strong base . This should not be placed near the edge of the pit or excavation.
4.No unauthorized persons are allowed on the crane.
5.No inflamable materials are kept on the crane.
6.Capacity marking as stated above should be displayed on the crane.
7.At least two winding ropes should always be on the wire rope drum of the crane.

THE CRANE SHOULD NEVER BE PUT INTO OPERATION

1.There is crack in structure.
2.There is damage in the wire rope
3.Hook does not rotate freely or the locking nut on the hook is missing
4.Coupling bolts/pins or their nuts or leather/rubber bushes missing.
5.The power collector is touching the adjacent trolley lines.
6.Rubber material or the wooden platform from the crane cabin is missing.
7.Earthing connections from the controllers and other electrical equipment missing.
8.Any unauthorized lerson is near the power line or on the crane.

THREE MAJOR HAZARDS :-

ELECTRICAL HAZARDS

nearly 50 percent of overhead crane accidents are the result of machinery coming into contact with a power source during operation. Power line contact is literally defined as the inadvertent contact of any metal part of a crane with a high-voltage power line. Power line contact most often occurs when the crane is moving materials nearby or under energized power lines and the hoist line or boom touches one of them. Usually, the person who is electrocuted is touching the crane when it comes into contact with the power line. But, the danger is not just limited to the operator. It extends to all personnel in the vicinity.A single contact with power lines can result in multiple deaths and injuries.

Preventive measures :-

The area within a 10-foot radius of a power line is considered an unsafe work area—or danger zone—and it must be clearly marked on the ground by insulated barriers, fences, tape, etc. 

OVERLOADING

80 percent of all crane upsets and structural failures can be attributed to exceeding the crane’s operational capacity. When a crane is overloaded, it is subject to structural stresses that may cause irreversible damage. Swinging or sudden dropping of the load, using defective components, hoisting a load beyond capacity, dragging a load and side-loading a boom can all cause overloading.

Preventive measures :-

workers to provide formal training for all crane operators, but operator certification is only required for operators using equipment with a maximum manufacturer-rated capacity of 2,000 pounds or less. Employees who are not qualified are only permitted to operate equipment as operators-in-training with a certified trainer. Formal training should ensure a working knowledge of crane load charts, and on-the-job training is a great preventative measure if the trainer is qualified.

MATERIALS FALLING

Falling materials is a major concern at any work place or job site using overhead cranes. Visual impairment, two-blocking, slipping, mechanical failure, or operator incompetency can all result in serious injuries or fatalities. If materials are not properly secured, for instance, the load can slip and land on workers in the vicinity or cause major damage to property. For larger or mobile cranes, undesired movement of material can pinch or crush workers involved in the rigging process.

Preventive measures :-
One way to reduce the risk of falling materials is to perform regular maintenance of hoists. Load testing maintenance ensures that you know how many pounds the hoist can handle, and it helps to maintain good working condition. Maintenance should always be treated seriously when it comes to heavy machinery. If a moving part on an overhead crane wears out or breaks the hoist, it can cause serious damage. Performing regular maintenance ensures the hoist and overhead crane remain in good working order and that all operations run smoothly.