Rail gnawing prevention for industrial crane safety

Crane rail gnawing is one of the commonly happened situation during the running process of industrial crane. Rail gnawing once happens to the industrial cranes, it may cause harm and serious crane accident, which are highly dangerous to the safety of your overhead crane and gantry crane. 

Rail gnawing

Rail gnawing

So what is the crane rail gnawing of industrial crane？
Rail gnawing generally refers to the mutual friction between the wheel rim and crane rail. Normally，it has a certain gap between the wheel and crane rail. In the process of traveling，they will not contact. But sometimes，when the crane wheel run off track center，crane rail gnawing occurs.

Form of the rail gnawing

• The wheel rim inside and the track on the side has a blackspot.
• When industrial crane traveling，bodywork produce skewed，and the wheel will be skewed.
• When industrial crane traveling，it will issue a loud voice.

 Rail gnawing adverse consequences to industrial crane

Shorten the service life of the wheel

Normally，the life of the wheel is about 10 to 15 years，but for some industrial cranes which is serious crane rail gnawing，the wheel of life is only one year or a few months.

Wear track

The lateral force generated when rail gnawing will cause the track offset.
Increase the running resistance

Increase the motor load, increase the cost

Plant loading conditions changed，affect safe use of industrial cranes.

A risk of derailment

the case of serious rail-gnawing ， wheels may climb up to the rail top, cause a derailment accidents.

The degree of rail gnawing

Low level： ”I” , first gear, startup slowly by the controller ，a short distance after coasting brake.
Middle level：”I”, first gear, don’t start，”II”, second gear, startup slowly by the controller，when braking，no movement inertia，rim has wear and tear.
High level：”II”, second gear, don’t start，reverse operation within 10 meters，industrial crane body skewed peak，began to gnaw rail.

Rail gnawing causes analysis

• 1. The diameter of the two active wheels differ too much.
• 2. The installation of four wheels position error，As shown in figure，D1>D2,orL2>L1.

• 3 The level of the wheel deflection error：namely，the center line of the wheel tread surface and the center line of the track has an angle on the horizontal direction.

Rail gnawing discriminant standard

General with the wheel rim wear to the seriousness of the discriminant gnaw

rail，flange wear is if reaches 1 mm is the serious rail gnawing，need repairing immediately.

Technical measures of avoid the rail gnawing

1 Reduce the diameter of the wheels：the diameter of the two active wheels should not exceed 0.2% of its base diameter，the diameter of the two passive wheels should not exceed 0.5% of its base diameter.

2 The adjustment of installation error: industrial crane wheels of diagonal and span of

deviation shall not be more than ±7mm ，trolley wheels of the diagonal and gauge deviation should not exceed±3mm，idiostatic of wheels should not exceed ±2mm.

3 The adjustment of industrial crane traveling mechanism: bearing and brake which is driving respectively，tightness should be adjusted to the same，If change the gear reducer and coupling, etc.，should replace them on both sides at the same time.

4 The adjustment of Tapered roller bearing clearance.

• Bearing nominal diameter（mm): 30~50,  50-80, 80-120
• Axial clearance（um): 80-150,  120-200,  200-300

From what has been discussed above，which is Manufacturing by our DONGQI GROUP, before leaving the factory are various deviation detection mentioned above，ensure that in the normal range. So the customer when buying our industrial crane，as long as the correct installation， normal maintenance,，rail gnawing won't happen.

Please contact us freely for more information on Crane Rail Gnawing. 

Related reading:

Overhead crane rail & gantry crane rail: Various crane rail dimensions and specifications