Other Crane Tracking Issues
There are several crane issues that could cause abnormal tracking that is unrelated to your runway or bridge squareness including the following which should be verified before performing major runway alignment or repair.
Different diameter bridge wheels: This is much more prevalent than one would think. It is very unlikely that your crane was originally supplied with different diameter wheels; however many crane applications have the load traveling predominantly on one side of the runway. This leads to faster wear on the loaded wheels and over time dissimilar wheel diameter.
Bent end trucks: A collision with another crane or with the end stops can cause a bent end truck. Often the end stops are not installed square to each other and this allows all the force of a collision into the one end truck.
Bridge brakes not releasing simultaneously: a delayed brake release will cause the crane to run askew.
Bad bridge bearings: This will cause drag on one side and also cause the crane to run out of square.
Bad bridge couplings: This causes tracking issues because torque is not transmitted evenly to both sides of the bridge allowing them to run out of square.
Different RPMs on drive wheels: This can be caused by faulty or mismatched motors or gearing.
Different torque values on drive motors: This can cause the end trucks to accelerate at different speeds again causing a squareness issue.
Out of square bridge wheels: If one or more of the bridge wheels are toed out or in, they will force one side of the end truck to drive the crane toward the rail. This will result in one side dragging behind the other.
Crane Built out of Square: Sometimes cranes are simply out of square from initial fabrication, installation or modification. This can be the case if one girder is shorter than another, there are mismatched end ties on bogie trucks. or misaligned girder connections.
The expert engineers at CRANE 1 are trained to identify these conditions and sort them out to bring your cranes back to proper squareness and true running condition. This helps to limit wheel wear as well as wear to the crane rail and other mechanical components of the crane and runway system.