Working Principle of Gun Drilling When gun drilling is working, the coolant is sent to the cutting part through the circulation cooling system by the high-pressure pump 

through the inside of the drill pipe to cool and lubricate the tool, and rely on the pressure of the coolant to push the chips from the inner wall of the hole to the drill pipe. 

The "V" shaped groove on the top is discharged. When working, the gun drill can be driven by the machine tool spindle for rotational processing, or the gun drill can be fixed 

while the workpiece rotates. When the workpiece rotates, the shape and position tolerance of the hole processed will be better.

2. The structure of the gun drill The gun drill consists of three parts: drill tip, drill rod and tool holder.

Drill tip: The drill tip is the most important part of the gun drill. It is responsible for the important drilling work. In order to ensure the accuracy of the hole to be processed, 

a guide block is designed on its circumferential part, which is guided by the guide hole at a time. The knife can produce high-precision holes. There are many types of drill tip 

structures to choose from according to different processing conditions.

Drill pipe: The drill pipe is usually designed with a "V" structure, and the outer diameter is slightly smaller than the drill tip. On the premise of ensuring sufficient strength and 

stiffness of the drill pipe, the coolant hole and chip removal space of the drill pipe should be maximized as much as possible. , to facilitate the cooling, lubrication and chip 

removal of the drill tip.

Tool handle: The handle part is mainly used to transmit power.

3. The structural form of the drill tip. The geometry of the drill tip directly affects the cutting performance of the gun drill and the accuracy of the hole being processed.

4. The use of gun drills Gun drills are often made in the form of a single-edged cutter head. It is generally suitable for processing small and deep holes with a diameter of 

Φ2-Φ20mm. The length-to-diameter ratio can reach 80 times. The maximum length of the gun drill can reach 3000mm. The workpiece to be processed The surface 

roughness is Ra0.4-1.6, the aperture accuracy is IT7-9, the hole has high linearity, and the orifice has no burrs, and the accuracy has good repeatability. It is widely used in 

automobile manufacturing, aircraft and ship manufacturing, machine tool manufacturing and other industries. The main processing objects are: cylinder block, cylinder head, 

crankshaft and various engine parts.