CNC milling machines are considered universal machine tools, capable of producing many different components. There are many techniques available to increase the productivity of the cutting process. Optimizing the cutting parameters, improving the tool path, optimizing the coolant, lubricant, and tool types are just to name a few. However, productivity of machine tools is typically more affected by how long it takes to setup to begin producing the next part. Reducing the changeover time results in higher productivity of the machine tool and reducing the quality escapes, which has a direct impact on overall equipment effectiveness (OEE).
One of our clients engaged Techam Solutions to review a milling cell that was assigned to machine components within a same product family in varying batch sizes. Productivity issues, quality issues and availability were the fronts that needed to be addressed.
Many steps were taken to reduce changeover and improve machine utilization
Detail analysis on Internal and External elements of changeover along with detail time studies.
Multi part fixture to eliminate setup time for several parts
Automatic simultaneous hydraulic clamping to minimize clamping time
Utilizing a pallet changer to convert this internal changeover element to an external one
Robotic loading and unloading of parts into the fixture on the pallet changer to reduce loading/unloading time
Adding part presence sensors to eliminate down time and quality issues due to part misplacement
Redesigning the fixture to handle all part sizes within the product family to eliminate the setup time from batch to batch
Through combination of lean techniques and automation solutions the setup time was reduced by 45%; from 10 minutes per part no. to 5.5 min and zero adjustment.