What is deep hole drill processing
Author：山東精鉆精密機械有限公司
Source：http://www.vvac.cn
Time：2021-05-07
1. Deep hole
In the machinery manufacturing industry, cylindrical holes with a hole depth of more than 10 times the hole diameter are generally called deep holes. According to the ratio of hole depth to hole diameter (L/D), deep holes can usually be divided into three types: general deep holes, medium deep holes and special deep holes.
(1) L/D=10～20, it belongs to general deep hole. It is often processed with a long twist drill on a drill press or a lathe.
(2) L/D=20～30, belonging to medium deep hole. Often processed on a lathe.
(3) L/D=30～100, it belongs to special deep hole. It must be processed on a deep hole drilling machine or special equipment using a deep hole drill.
2. Difficulties in deep hole processing
(1) The cutting situation cannot be directly observed. Judge chip removal and drill wear only by sound, watching chips, observing machine load, oil pressure and other parameters.
(2) Cutting heat is not easily transmitted.
(3) Chip removal is more difficult. If the chip is blocked, it will cause damage to the drill.
(4) Due to the long drill rod, poor rigidity, and easy vibration, the axis of the hole is easy to deviate, which affects the processing accuracy and production efficiency.
3. Types of deep hole drills
Deep hole drills are divided into external chip removal and internal chip removal according to the chip removal method. The external chip removal has gun drills and integral alloy deep hole drills (can be divided into two types with cooling holes and no cooling holes); internal chip removal is also There are 3 types of BTA deep hole drills, ejector drills and DF system deep hole drills.
