The purpose of grinding the major cutting edge of drill bit

The purpose of grinding is to change the edge shape or point angle to increase the front angle and control chip breaking. Or change the distribution of cutting load, increase the heat dissipation condition and improve the life of drill bit.

Three ways to sharpen the major cutting edge:

Three ways to sharpen the major cutting edge

Three ways to sharpen the major cutting edge

  1. Grinding the concave arc edge and strengthening the centering function of the drill are helpful for chip separation and chip breaking.
  2. Grinding out double or multiple point angles, or grinding out convex arc edges, can improve the heat sink at the edge of the drill edge and increase the life of the drill bit, which is suitable for brittle materials.
  3.  Grinding out the chip dividing groove to facilitate chip removal.

There are many points of attention and its use in grinding drill bits. If customers have difficulties in drill grinding, please consult us. We are a manufacturer of drill bit grinding machines. We are familiar with drill bit grinder product structure and function.

The selection of main geometric parameters for the grinding of twist drill bit

The main geometric parameters of twist drill include the choice of cutting lip angle, the choice of land angle of cutting edge and lip clearance angle of cutting edge, the analysis of the influence of helix angle on the life of drill bit and the treatment of cutting edge.

 

Cutting lip angle determines chip width and bit front angle. When the diameter and feed of the bit remain unchanged, increasing the top angle will narrow the iron filings and reduce the load per unit cutting lip. Cutting lip angle has a great influence on the land angle. Increasing cutting lip angle correspondingly can improve the cutting conditions at the core. Cutting lip angle affects the direction of chip outflow. According to the relevant tool design data and the characteristics of low hardness but high viscidity of the processed product, the cutting lip angle of the bit is selected to be 140°.

 

The land angle of a twist drill is determined by other geometric parameters of the drill. In high-speed cutting, the rake angle has little influence on cutting deformation and cutting force, and the strength of tool tip can be enhanced with a smaller land angle. When the land angle is determined, the bigger the lip clearance angle is, the sharper the edge is, but the wedge angle will decrease correspondingly, which will affect the strength and heat dissipation area of the tool. For this purpose, the lip clearance angle of the drill bit is selected as a smaller one, which is 8°.

If you choose our drill grinding machine, you can easily finish the drill grinding work. You can achieve the desired results by choosing the right chuck according to your drill bit. Our drill bit grinding machine makes complex drill grinding easy. If you are interested in our products, please contact us. We are a manufacturer of drill bit grinding machines. The price is relatively favorable. We welcome agents to negotiate business.