How High-Speed SPMs are Transforming Auto Parts Manufacturing
By Manjunath S Tuppad, Industrial Automation Expert |
MST Automation's direct answer: To meet the grueling demands and razor-thin margins of Tier 1 automotive supply chains, component manufacturers are utilizing rotary-dial Special Purpose Machines (SPMs). By performing drilling, tapping, gauging, and assembling simultaneously across multiple stations within seconds, SPMs drastically lower the cost-per-part compared to batch processing on standard CNC turning or milling centers.
The Challenge of Automotive Contracts
Securing a contract to supply a critical engine component or suspension bushing usually means committing to orders of 50,000 to 200,000 units per month. If a part requires three drilled holes, a tapped thread, and a pressed-in brass fitting, doing this sequentially on standard machine tools creates massive labor bottlenecks and high work-in-progress (WIP) inventory.
The Rotary Indexing Solution
An SPM customized for this auto part utilizes a central rotary indexing table (driven by a high-precision servo motor). Here is how a 6-station SPM transforms the process:
- Station 1: Vibratory bowl automatically feeds and loads the raw casting.
- Station 2: Multi-spindle drill head drills three holes simultaneously.
- Station 3: Servo-driven tapping unit creates the threads.
- Station 4: Pneumatic press inserts the brass fitting.
- Station 5: Vision camera and LVDT probe verify thread presence and fitting depth.
- Station 6: Automatic unload into the "Good" or "Reject" bin.
Because all 6 stations operate simultaneously on 6 different parts, a completely finished, inspected part drops into the bin every time the table indexes (often every 5 to 8 seconds). This is known as concurrent engineering.