Does the crane experience rail biting, and how can you easily determine if a crane is experiencing rail biting?

Whether the crane is experiencing rail biting during operation can be determined based on the following indicators:

1. The sides of the rail show bright marks, with severe ones accompanied by burrs; the inner side of the wheel flange has shiny spots.

2. There are bright spots on the top surface of the rail.

3. During operation, the crane experiences a noticeable change in the gap between the wheel flange and the side of the rail over a very short distance.

4. When the crane starts or brakes, the vehicle body moves diagonally and sways violently.

What could cause a crane to "bite" the rail? First, it could be due to issues with the track itself; second, it might stem from problems within the transmission system.

Railway-related reason: Due to poor installation quality of the tracks, the two rails have developed excessive misalignment. As a result, the crane inevitably experiences rail biting during operation. In such cases, the rail-biting phenomenon typically occurs at specific sections along the track.

1. Excessive relative elevation differences between the two rails cause one end beam of the bridge crane to sit higher while the other is lower. During operation, this imbalance leads the crane to shift laterally toward the lower side, resulting in rail biting—a phenomenon where the wheel flanges either tightly press against the outer edge of the rail (on the higher side) or the inner edge (on the lower side).

2. Excessive deviation in the horizontal straightness of the two rails—during track installation, if the rails are not perfectly aligned and exhibit curvature—can lead to significant horizontal bending. When this deviation exceeds the allowable span tolerance, it inevitably causes the wheel flanges to rub against the sides of the rails, resulting in rail biting.

3. When the top surfaces of two adjacent rails on the same track are not at the same level, the crane experiences lateral movement as it travels over the rail joint, leading to rail biting. In such cases, the wheels typically produce a metallic clanging sound when they reach the joint.

4. If there is oil, water, ice, or frost on the top surface of the rail—these conditions can cause the wheels to slip while running on the track, leading to uneven alignment of the vehicle and potentially causing rail wear due to sideways movement.

Cause related to the transmission system: Excessive manufacturing errors in the transmission system or significant wear during operation can result in unequal running speeds between the two driving wheels of the trolley, causing the vehicle body to drift and leading to rail biting.

1. Unequal gear backlash in the transmission system or loose keyways on the shafts—particularly in two separately driven transmission mechanisms—can cause the two driving wheels to rotate at different speeds. This discrepancy leads to uneven vehicle movement, resulting in the car body drifting off course and causing rail biting.

2. The two drive mechanisms have differently adjusted brake tensions. During startup and braking, if the brake clearance on one side is too large while the clearance on the other side is too small, it can cause the vehicle body to drift sideways, leading to rail biting.

3. An excessive speed difference between the two electric motors—especially in the case of separately driven systems, where no mechanical link exists between the two mechanisms—can cause one side of the crane to move faster while the other side lags behind during operation. This imbalance leads to the crane body tilting and, ultimately, results in rail biting, compromising both safety and efficiency.