Producing High Quality Rivets with CNC Machines(fastener types Vito)
- source:ZIEG CNC Machining
The material used to make rivets directly impacts their strength and performance. Common materials for industrial rivets include various steel alloys, aluminum, and titanium. The choice depends on factors like required load capacity, corrosion resistance, and cost. For example, stainless steel provides good corrosion resistance while alloy steel offers high strength.
Aluminum is lightweight and titanium has the highest strength-to-weight ratio. The material stock starts as rod, bar or wire and gets cut to the required blank size for CNC machining. Proper material certification and traceability is critical for aerospace and defense applications.
CNC Machining Benefits
CNC machining uses programmable computer controls to automate fabrication. This enables very precise, repeatable machining of rivet blanks. Benefits of CNC machining include:
- Accuracy and Consistency: CNC machines can repeatedly hit tolerances down to +/- 0.001 inches. This produces uniform, precision rivets.
- Complex Geometries: CNC machines can create complex rivet shapes beyond what's possible manually. Custom designs optimize strength, weight and performance.
- Efficiency: CNC automation provides high throughput. Rivets are machined faster than manual methods.
- Flexibility: Engineers can easily update CNC programs to change rivet designs and parameters. New rivet specs can be accommodated without investing in new machinery.
- Quality Control: Monitoring CNC processes gives real-time data to minimize defects and document compliance.
CNC Machining Operations
Turning, milling and drilling are the primary CNC operations used to fabricate rivet blanks from rods, bars or wires. Typical process steps include:
1. Facing: This flat machines the stock end to create a smooth, perpendicular reference surface.
2. Turning: The stock gets machined to the required diameter and contours. Turning gives rivets their external cylindrical shape.
3. Drilling: Holes get drilled into one or both ends of the rivet blank. Drilling determines the internal hole size.
4. Milling: Keyways, flats and other non-round profiles get milled into the rivet head or shank. This gives unique shapes for orientation and strength.
5. Grooving: Narrow cuts made on the periphery give riveted assemblies a way to vent pressure and gases.
6. Cutting: The machined blank gets precisely cut off to length resulting in the finished rivet body. Automated feeding indexes the next blank.
Secondary finishing operations like deburring, washing, coating and heat treatment may also be employed. CNC programming synchronizes the tools, speeds and feed rates to create the complete machining sequence.
Setting Up for Success
Optimizing CNC rivet manufacturing requires attention to details beyond the machines:
- Fixtures: Workholding fixtures securely locate and position blanks for accuracy cutting after cutting. Minimal runout is crucial.
- Tooling: Carbide and diamond cutters must stay sharp. Built-up edge on tools degrades hole precision. Proper insert grades and geometries optimize chip formation, tool life and surface finish.
- Coolant: Effective coolant evacuation prevents recutting chips. This avoids built-up edge and ensures dimensional accuracy. Coolant also controls heat and flushes away chips.
- Inspection: Production sampling verifies critical dimensions stay in tolerance. SPC charts help identify any creeping out-of-spec conditions before they become defects. Real-time gauge feedback allows adjustments at the machine.
- Maintenance: Schedule routine maintenance like lubrication, vibration analysis and calibration. Address any worn components like ballscrews before they harm quality.
- Housekeeping: Contamination can quickly ruin perfectly good machining processes. Keep machines free of dirt, debris and leaks.
When these best practices are implemented, CNC machining produces rivets with exemplary quality. The automation and repeatability inherent to CNCs enables both high volumes and expensive precision rivets to be manufactured cost effectively. This makes quality rivets accessible across many industries. The end results are durable products and structures built to last thanks to top-notch rivets cranked out by CNC machining. CNC Milling CNC Machining