Causes and treatment of rail gnawing of bridge crane

Rail gnawing of bridge crane is a kind of strong wear caused by contact between wheel flange and rail side. Such as the follow:

Wheel gnawing rail image of bridge crane:

(1) There is a bright mark on the side of the rail, and there are burr or strip iron flake in serious cases.

(2) Bright spots and wheel rims on the inside.

(3) When the crane is started and braked, the car body will be deflected and twisted.

(4) When the crane is running, the clearance between the wheel rim and the rail changes obviously in a short distance (10 m).

(5) When the crane is running, it will make a loud "hissing" rail gnawing sound. When the rail gnawing is particularly serious, it will make a "noise" impact sound and even climb the rail.

Cause 1: rail problem - the relative elevation deviation of two rails exceeds the standard

The relative elevation deviation of rail exceeds the standard

Solution: by adjusting the rail pressing plate and base plat.

Cause 2: rail problem - excessive horizontal bending of rail

Rail gnawing due to rail out of tolerance 

Solution: straighten or replace.

Cause 3: rail problem -- the overall or partial out of tolerance of two rails

Solution: straighten or replace.

Cause 4: rail problem - rail foundation sinking or steel structure deformation of roof beam

Solution: On the premise of not endangering the safe use of the workshop, it can be solved by strengthening the foundation, adding pad under the rail and strengthening the steel structure of the house beam.

Cause 5: wheel problem - the diameter deviation of the two active wheels is too large

The running speed of the wheels on both sides is not equal, and the car body runs askew, resulting in rail gnawing.

Solution:

Scheme 1: the wheel tread wear is not uniform, resulting in excessive deviation. The tread can be overlaid, then turned, and finally quenched.

Scheme 2: for rail gnawing caused by unequal tread diameter of two driving wheels or incorrect installation of wheel taper direction, the wheel should be replaced to make the diameter and size equal or the taper direction be installed correctly.

Cause 6: wheel problem - the horizontal and vertical deflection of the wheel is too large

Rail gnawing is caused by vehicle body skewness or uneven wear of wheel rolling surface.

Solution:

Scheme 1: the bridge deformation makes the horizontal and vertical deflection of large wheels out of tolerance. Correct the bridge frame first to make it meet the technical requirements. If there is still rail gnawing phenomenon, the wheel can be adjusted

Scheme 2: if the bridge is OK, a pad of appropriate thickness can be added to the fixed key plate of the angular bearing box. When adjusting the horizontal deflection, pad the vertical surface of the wheel group; when adjusting the vertical deflection, add pad on the horizontal plane of the wheel group.

Cause 7: wheel problem - wheel tread selection error

There are two types of wheel tread, cylinder and cone, which are easy to be ignored and wrong selection, so that the machining error of large wheel can not be absorbed and transformed.

Solution: choose the right wheel form

Cause 8: wheel problems - wheel rail width, diagonal are not equal

It causes the car body to lose the proper movement when running, resulting in rail gnawing.

Solution:

Try to choose and adjust a wheel set, and it is better to adjust the driven wheel set to solve the problem.

Diagonal adjustment: in order not to affect the concentricity and repair workload of the centralized drive shaft, generally adjust the driven wheel as much as possible, do not adjust the driving wheel, cut off the key plate of the wheel group, and weld the key plate after adjustment.

Wheel span adjustment: reduce the spacing ring of wheel bearing on one side and increase the other side; or enlarge the bolt hole of bearing box on the bending plate of end beam and move the positioning key. 

Cause 9: Bridge reason - the wheel rail change of crane caused by the main beam down warping

Solution: the wheel can be moved and the gauge can be changed to repair. If we want to solve the problem fundamentally, we should repair the main beam. We must not use the method of moving the trolley rail, because cutting and welding the rail pressing plate will cause the main beam to further bend down and bend inward.

Cause 10: drive system - two motors out of sync

Rail gnawing caused by asynchronous motor when driving separately

Solution:

The motor should be repaired or replaced to synchronize the motor. Replace the motors on both sides with those of the same model and manufacturer

Cause 11: transmission system - gear transmission system clearance is uneven or the key on the drive shaft is loose

Uneven gear clearance and loose shaft key will cause inconsistent speed of two driving wheels, which will lead to body torsion and rail gnawing.

Solution: the relevant clearance should be adjusted to synchronize the starting and braking.

Cause 12: transmission system due to oil contamination on rail or wheel

Solution: oil should be removed

Cause 13: transmission system brake torque is not equal or improper selection

Rail gnawing caused by excessive braking force and too fast braking speed

Solution: the brake should be adjusted to make the braking torque equal.

Cause 14: for rail gnawing caused by loose bolts or no backstop pad in the press plate during use

Solution: the bolt should be tightened: add the pressing plate backstop pad, and adjust the rail to the standard.

Bridge Crane Of Dejun Hoist and Crane

DJCRANES have professional engineer team can help you to customize the crane for your workshop and plant. If any requirements please do not hesitate to Contact Us. The perfect service is waiting for you!