Fit Bolt Repairs

A 4000 HP motor with a Built-In, Drive-Flange was running in a steel pipe mill for Over 30yrs

The motor flange was coupled to another flange to drive the mill gear box.

The bolt hole bores in the Motor flange were taper, built by the manufacturer to accept Taper Fit Bolts of 55 to 70mm Taper.

Due to excessive load and wear & tear, Taper bores had become oval by 16mm. This condition resulted in routine shearing of fit taper bolts and shutdown of the entire mill, causing great loss of production and downtime.

We were called to provide a solution to this problem.

We devised on site machining equipment, and under took the job of repairing all the Ten bolt holes, back to perfectly, indexed bores and taper diameter, resulting in perfect mating with the mill gear box flange. The job was completed in 4 days and, to the full satisfaction of the user.