Crane Trolley Drive: Mystery Solved By Telemetry
The coupling bolts on a crane trolley wheel drive repeatedly needed tightening. What was the cause? Using Binsfeld telemetry and a Micro-Measurements strain gage, the torque on the drive shaft was measured during operation to see if excessive dynamic loading was occurring.
The measurements revealed that when the brakes were applied the dynamic torque was 4 times the rated load. The design of the coupling relied on the clearance holes for the bolts and friction across the coupling halves to carry the torque. The dynamic oscillating torque was causing the bolts to loosen. An adjustment to the braking system reduced the dynamic torque by 90%. Additionally, it was recommended that the coupling be retrofitted with body fit clamping bolts.