Symptoms of hollow drill bit damage include the following: alloy cutting edge fracture, alloy edge falling off, cutter body fracture, alloy cutting edge becoming blunt and inoperable. The above four symptoms are introduced in detail.
 
1. Symptoms of alloy blade cracking:
 
There are two main reasons for this, one is normal wear and tear, and the other is improper use.
 
The clinical manifestations are cracks on single or multiple edges of the alloy blade. The cracks are small, that is, the cutting edge is worn. Due to the wear of the blade, drilling operations cannot be performed, resulting in damage to the hollow drill bit.
 
2. The overall alloy blade falls off:
 
The entire alloy blade falling off is a serious drill quality problem for hollow drill bits. This means that when drilling during welding, the quality of the drill bit is unqualified due to insufficient welding strength. Because the drill edge is subjected to cutting reaction force during the drilling process, the alloy cutting edge falls off as a whole.

 
3. Symptoms of blade breakage:
 
Cutter body fracture is a rare damage state of the core drill bit, which is characterized by overall horizontal or vertical overall fragmentation. This is caused by substandard engineering of the drill body.
 
4. Symptoms of alloy edge becoming dull:
 
Blunting of the alloy cutting edge of hollow drill bits is a common cause of drill bit damage. This happens after the drill has been used for a period of time. In this case, the alloy edge of the core drill bit becomes dull due to normal wear and tear. The cutting edges of previous alloy blades were very sharp. Alloy blades may develop rounded edges when the blade becomes dull. Therefore, while drilling, we cannot continue drilling.