Our customer is using a parts washing cell with a conveyor to feed dirty parts through a Ransohoff tunnel parts washer. They needed part holding fixtures that would bolt to the conveyor and hold parts securely through the high pressure spray wash and drying cycle. The parts to be washed had several machine surfaces that needed to be protected from scratching. And the parts had several blind holes that needed the direct spray of the parts washer to be cleaned properly so the fixture could not block these holes.
The customer’s part is an oddly shaped casting, with several machined surfaces, and with several holes that must get a direct spray to be effectively cleaned. Three M Tool design process started by creating a digital model of the customer’s part in SolidWorks. With the part in SolidWorks, it was very easy to rotate the part in space to find the best orientation to clean the part effectively and to hold the part securely. Our design uses 1/4″ diameter stainless steel rod to create a cradle for the part without obstructing the spray from any critical areas. The cradle design has several poka-yoke, or fool-proofing, features that would only let the operator load the part one “correct” way in the fixture. The fixture has Snap-on UHMW strips to protect the machined surfaces for being scratched be the stainless steel rod. Two mounting tabs with bolt holes on the bottom face match the mounting points on the conveyor. The part holding fixtures are 304 Stainless Steel Construction throughout and are Natural Finish.