How To Check Crane Accessories 1 ?

How To Check Crane Accessories 1 ?

 

Crane accessories are extremely important for bridge cranes and gantry cranes, so how to check the quality of crane accessories after purchasing a crane?

 

Please carefully review the following content and correspond to product accessories. Our company organizes common crane accessories and inspection methods as follows:

 

1. Wire rope

 

(1) The number of broken wires within a lay length should not exceed 10%, and the amount of wear and corrosion on the surface of the steel wire should not exceed 40% of the original diameter (the wire rope for lifting hot metal or dangerous crystals, the scrapping standard for broken wires is taken as 1/2 of the general crane).

 

(2) The wire rope should be free from severe deformation such as kinks, dead angles, hard bends, plastic deformation, hemp core prolapse, etc., and the lubrication condition is good.

 

(3) The length of the wire rope must ensure that when the hook is lowered to the lowest position (including the pit), the wire rope remaining on the drum is not less than 3 turns.

 

(4) There should be more than 2 fixed pressure plates at the end of the wire rope.

 

 

2. Pulley

 

(1) The pulley rotates flexibly, clean and smooth without cracks, and there is no defect in the wheel rim or damage to the wire rope.
 

(2) When the uneven wear of the wheel groove reaches 3mm, or the wall thickness wear reaches 20% of the original wall thickness, or the diameter reduction of the bottom of the wheel groove reaches 50% of the wire rope diameter, the pulley should be scrapped.
 

(3) The pulley guard should be installed firmly without damage or obvious deformation.
 

 

3. Hook
 

(1) The surface should be smooth and clean, without defects such as cracks and sharp angles. Repair welding is not allowed for defects on the hook.
 

(2) The hook should rotate flexibly, and the positioning bolts and cotter pins must be fastened intact.
 

(3) Cracks are strictly prohibited on the dangerous section of the lower part of the hook and the undercut section of the threaded part of the hook tail.
 

(4) The wear amount of the dangerous section should not exceed 10% of the original size. The wear amount of the plate hook bushing should not exceed 50% of the original size, and the wear amount of the mandrel should not exceed 5% of the original size.
 

 

4. Brake
 

(1) The action is flexible and reliable, and the adjustment should be moderately tight, without cracks, and the spring has no plastic deformation and no edge.
 

(2) When the brake wheel is released, the gap between the brake shoe and the brake wheel should be basically equal. The maximum opening of the brake band (one side) should be ≤ 1 mm, and the lift should be ≤ 0.7 mm.
 

(3) The braking friction surface of the brake wheel must not have defects that hinder the braking performance, and must not be stained with oil or paint.
 

(4) The unevenness of the wheel surface should be less than 1.5 mm, the wear amount of the rim thickness of the brake wheel of the lifting and luffing mechanism should be less than 40% of the original thickness, and the wear thickness of the rim of the brake wheel of other mechanisms should be less than 40% of the original thickness 50%.
 

(5) For hoisting hot metal, flammable and explosive dangerous goods, or cranes that may cause major danger or loss after hook slipping, the lifting mechanism should be equipped with two sets of brakes.
 

5. Limit limit and interlocking device
 

(1) The over-winch limiter should ensure that when the hook rises to the limit position (electric hoist > 0.3 m, double beam crane > 0.5 m), it can automatically cut off the power supply. The newly installed crane should also have a lower limit limiter.
 

(2) The operating mechanism should be equipped with a travel limiter and a mutual inductance limiter to ensure that when the two cranes are traveling at a distance of 0.5 m from each other, the crane will automatically travel at a distance of 0.5 to 3 m from the limit end (depending on the tonnage). Cut off the power.
 

(3) When the cage (car) of the elevator (or elevator) crosses the upper and lower end stations by 30-100 mm, the overtravel switch should cut off the control circuit; when it crosses the end station leveling position by 130-250 mm, the limit switch should cut off the main Power does not automatically reset. Knife switches are not allowed for limit switches.
 

(4) Luffing type cranes should be installed with maximum and minimum limit devices to prevent the boom from tilting forward and backward. When the amplitude reaches the maximum or minimum limit, the root of the boom should touch the limit switch to cut off the power supply.
 

(5) Door compartment interlocking protection devices shall be installed on the door of the bridge crane cab, the hatch leading to the bridge frame, and the end beam doors on both sides of the crane; the landing door of the elevator (or elevator) must be equipped with mechanical and electrical interlocking devices. The car door should be equipped with an electrical interlock device; the safety cabin door on the top of the manned elevator car must be equipped with an interlock protection device; the manned elevator car door should be equipped with a sensitive safety touch panel.
 

(6) For hoisting machinery operating in the open air, all kinds of limit switches and interlocking electrical parts should have anti-rain and snow measures.
 

 

6. Parking protection device
 

(1) Various switches are in good contact, reliable in action, and easy to operate, and can quickly cut off the power supply in an emergency (the electric hoist button box operated on the ground should also be equipped with an emergency stop switch).
 

(2) Buffers should be installed in the traveling mechanism of the large crane and the trolley, the sides of the four ends of the rail terminal column, and the bottom limit position of the lift (or elevator).
 

(3) All kinds of buffers should be installed firmly. Use rubber buffers, the thickness of the trolley is 50-60mm, and the thickness of the cart is 100-200mm; if hard wood blocks are used, the surface of the wood blocks should be equipped with rubber.
 

(4) The track end stop should be able to withstand the impact of the crane when it is running at full load. For cranes of 50t and above, overload limiters should be installed. Elevators should be installed with load limiters, as well as overspeed and out-of-control protection devices.
 

(5) The zero position protection of the bridge crane should be intact.