Factors affecting the tool life of gun drills and their corresponding solutions:
1. Improper Cutting Conditions
- Is the cutting speed too high?
- Is the feed rate too fast or too slow?
2. Machine Tool-Related Issues
- Is the spindle runout/tool runout excessive?
- Is the concentricity between the spindle and the guide bushing adequate?
- Is the clearance between the guide bushing and the tool too large?
- Is the vibration damping/support of the drill shank sufficient?
3. Tool-Related Issues
- Selecting the appropriate tool tip geometry (rake angles, clearance angles) and guide pad configuration;
- Is the tool length excessive?
- Is the regrinding/re-sharpening performed properly?
4. Cutting Oil / Coolant
- Selecting the appropriate cutting fluid (high-pressure additives, viscosity, etc.);
- Cleanliness level of the cutting oil;
- Oil temperature control.
5. Workpiece Material
- Is the material uniform in composition and structure?
