3.1 Drill tip wear
Reason:
1. The workpiece will move down under the force of the drill bit, and the drill bit will bounce back after drilling.
2. The machine tool is not rigid enough.
3. The drill bit material is not strong enough.
4. The drill bit beats too much.
5. The clamping is not rigid enough, and the drill bit slides.
Measures:
1. Reduce the cutting speed.
2. Increase feed capacity
3. Adjust the cooling direction (internal cooling)
4. Add a chamfer
5. Check and adjust the coaxiality of the drill bit.
6. Check whether the rear corner is reasonable.
3.2 Ligament collapse blade
Reason:
1. The workpiece will move down under the force of the drill bit, and the drill bit will bounce back after drilling.
2. The machine tool is not rigid enough.
3. The drill bit material is not strong enough.
4. The drill bit beats too much.
5. The clamping is not rigid enough, and the drill bit slides.
Measures:
1. Choose a drill bit with a larger back cone.
2. Check the spindle bit jump range (<0.02mm)
3. Drill the top hole with a predetermined heart drill.
4. Use a more rigid drill bit and a hydraulic chuck with a shrink neck sleeve or heat shrink kit.
3.3 Cumulant tumor
Reason:
1. Caused by chemical reactions between cutting materials and workpiece materials (low-carbon steel with high carbon content)
Measures:
1. Improve lubricants and increase the content of oil or additives.
2. Improve cutting speed, reduce feed rate and reduce contact time.
3. If you drill aluminum, you can use a polished uncoated drill bit on the surface.
3.4 Broken knife
Reason:
1. The screw groove of the drill bit was blocked by cutting and the cutting was not discharged in time.
2. When the hole is drilled quickly, the feed capacity is not reduced or the maneuver is changed to manual feed.
3. When drilling soft metals such as brass, the back corner of the drill bit is too large and the front corner is not polished, so that the drill bit is automatically rotated.
4. The drill blade grinding is too sharp, resulting in the phenomenon of blade collapse, and the knife has not been quickly returned.
Measures:
1. Shorten the cycle of tool replacement.
2. Improve installation and fixation, such as increasing the support area and increasing the clamping force.
3. Check the spindle bearing and sliding groove.
4. Use high-precision handles, such as hydraulic handles.
5. Use tougher materials.
