Kohler Company

The engine division competes globally by producing engines with longer life expectancy than the competition. Needing to produce a more cost competitive 15-20 Hp engine while maintaining quality standards, the company contacted Ellison Machinery & Robotics to assist in development of a manufacturing process for the oil pan component that would support this objective. Doing so would require a significant reevaluation of manufacturing technology employed in oil pan production, and refinement of process capabilities.

Assessment
The following determinations were made upon review of the process. The process would need to be compressed to a single operation, to simplify part flow and ensure a 1.67 Ppk quality requirement on all critical features. The cycle time would need to be brought under 4.5 minuets including part load / unload which could not exceed 6 seconds. A common fixture platform would be required to facilitate quick change over between the cylinder head and oil pan operations.

Solution
An Okuma MCV3016 VMC and Nikken NSZV300 Rotary Table with window fixture were used to allow the part to be machined on four sides in a single clamping. This supported the single operation and common fixture requirements, with ball locks on the trunion table enabling quick-change capability between fixtures. Machine rigidity, high-pressure coolant, and PCD tooling were used to optimize cut times, while Hi/Lo switchable clamp force limited casting flex during the machining of critical features in support of quality requirements.

End Result
The solution allowed the part to be completed in a single operation, while meeting the 1.67Ppk requirement on critical features. The cycle time exceeded requirements at 4.3 minutes, including a part load /unload time of just under 5 seconds.