Machining Shop
This pivot shaft arrived in the shop grooved and pitted from years of service. The lathe is polishing away the grooves and pits to restore a smooth surface and sized precisely to fit a new bearing made by Cat to work with the refurbished shaft.
The main frame, the ripper frame and other large structural components get sent to Empire Precision Machining. EPM is one of the Southwest's premier machine shops. It has lathes, mills and other machining tools large enough to work with the massive components common in the heavy equipment industry. Only a handful of Cat dealers in North America have machine shops on the same scale as Empire's.
EPM measures and tests each component to make sure it hasn't been bent or warped out of shape. Our machinists use sonegrams and other high-tech devices to test the metal for hidden cracks or weak spots. When they find flaws or weaknesses, they are repaired if possible. If a component cannot be restored to original specifications, we replace it.
Anyone who has spent much time driving cars or operating heavy equipment knows there is an obvious difference between the feel of a new, high-quality machine and an old or low-quality machine. We expect new cars and equipment to feel tight. When a machine feels loose or sloppy, we know it must either be old or poorly built.
Much of the looseness of an older machine is caused by worn bores in the structural metal. Worn bores allow bearings to move slightly within the bore causing an overall feel that's just not right. The movement accelerates wear on both the bearing and the bore.
(Left) This Computer Numeric Controlled mill is one tool EPM uses to restore bores in large components.
The enlarged section (below) shows a partially-completed remachined bore.The smooth, coppery area in back is finished. The rough, silver area in the foreground has not yet been touched.
EPM plays a key role in tightening the machine up to make it feel new again. EPM Machinists hone the bores to a slightly larger size and make them perfectly round to fit with the oversized bearings that Caterpillar builds specifically for the machine being rebuilt.
Some bearings, like those that carry the pivot shaft, have an inner diameter that's slightly smaller than the original bearing. EPM lathes shave the components that will ride in those bearings. The lathes produce a smooth finish, free of the grooves and scratches the component picked up during thousands of hours of hard work.
When EPM finishes its work, the pieces all fit together again as tightly and precisely as they did when they were new.
Next – Fabrication Shop
Hydraulic Shop
Engine Shop
HVC (High Velocity Coating)
Undercarriage Shop
Component Rebuild Center
Main Shop Reassembly
