Electric Motor Repair Case Study Part 4 - Stacking & Welding Core
After the laminations have been laser cut, they are brought over to our welding department to be stacked and welded. A stacking fixture is used to ensure the laminations are aligned properly. Additional components may also be used to help with the alignment of the core. Our engineers have developed standardized fixtures that allow high-tolerance alignment during the stacking process. Almost any additional or custom fixturing or secondary operations requirement can be produced in our on-site machine shop.
Once all of the laminations are stacked and aligned properly, the core is compressed and measured to make sure core length meets the print specifications. Once the core length is confirmed to be per print, it is then welded in multiple locations along the outside diameter.
After the welds have cooled, the compression plates are removed, and the stack is now ready to be installed back into the stator frame. This process may vary depending on the original design of the motor, but most involve welding the core to the frame and using dowel pins to hold the core in place. Some stator cores require an interference fit, which involves the use of thermal expansion and contraction effects in order to achieve the proper fit.
Now the core is ready for the final step, which is reinserting it into the frame, final inspection, packaging & shipping.