Generally, drilling holes where the ratio of hole depth to hole diameter is greater than 10 is called deep hole drilling. Due to the large length-to-diameter ratio, chip removal, 

cooling, lubrication and guidance have become difficult problems to solve when drilling with a general twist drill, and it is also difficult to meet the hole quality requirements.

   EB100 single-edge solid carbide gun drill: Processing range: Ф1.2-5.0mm, maximum groove length 300mm, suitable for processing almost all materials.

   EB80 single-edged carbide tip gun drill: processing range: Ф2-40mm, total length up to 3000mm, suitable for processing almost all materials.

   ZB80 double-edged carbide tip gun drill: processing range: Ф6-27mm, total length up to 1000mm, suitable for processing cast iron, aluminum and short iron chips 

non-metallic materials.

1. 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 drill pipe to cool and lubricate the tool, and the pressure of the coolant is used to remove the chips from the inner wall of the hole to the cutting part. The "V" 

groove on the drill pipe 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 is 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 an 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 feeds the tool at a time under the guidance of the guide hole. High-precision holes can be machined. There are many 

types of drill tip structures to choose from according to different processing conditions. The drill tip material is made of high-quality DK460UF ultra-fine grain carbide and 

coated with TiN, FIRE or MolyGlide coating. It has very high hardness and toughness, which greatly improves the drilling performance and service life of the gun drill.

Drill pipe: The drill pipe is usually designed in a "V" shape, with an outer diameter slightly smaller than the drill tip. Under 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 as large as possible. To facilitate the cooling, lubrication and chip removal of the 

drill tip. EB100 series drill pipes are ground from carbide integrated with the drill tip. EB80 and ZB80 series drill pipes are rolled from high-grade seamless steel pipes.

Tool handle: The handle part is mainly used to transmit power. Cobalt Company can provide 13 categories and a total of 42 specifications of standard tool handles for 

customers to choose from, and can also undertake the customization of non-standard tool handles.

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. The 

following five types of drill tip cylindrical shapes are combined with the differences of various drill tips. Angle grinding types are available for users to choose, ensuring that 

there is always one suitable for you according to different workpiece materials and requirements.

   Type G: Universal type, suitable for processing various materials, especially suitable for processing holes with a small hole tolerance range.

   Type C: Standard type, suitable for processing difficult-to-machine materials, such as high-alloy steel.

   Type E: Special type, suitable for processing various materials, especially suitable for processing holes with a large hole tolerance range.

   Type A: Special type, suitable for processing various materials under conditions where correct positioning is difficult.

   Type D: Special type, especially suitable for processing gray cast iron.

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 is 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.

Gun drills can be used in deep hole processing machines, machining centers, turning centers and other equipment that meet the cooling and guiding requirements of gun 

drills to process carbon steel, stainless steel, cast iron, non-ferrous metals, wood, plastics and other materials. We can tailor it to customers The machine tool condition 

provides optimized cutting process parameters to ensure the high cutting performance of gun drilling. In order to enable the gun drill to work stably and reliably for a long 

time, it is equipped with a series of compact and reliable desktop grinding gun drill devices: TBM116 and TBV116; these two sets of grinding fixtures are compact in structure, 

occupy a small area, and are easy to use. After a short training, , the user can use this fixture to grind the geometric parameters and dimensions close to the original knife, 

ensuring that the sharpened gun drill achieves processing performance and quality close to that of the new knife. The provided integrated rough and fine grinding diamond 

grinding wheel: DSS125, can ensure that the gun drill can complete rough and fine grinding in one clamping, which greatly improves the efficiency and quality of grinding. 

Matching tool accessories: drill sleeves, sealing sleeves and support seats, etc., ensure the smooth drilling of the gun drill.