Deep hole drilling depth analysis of 3 machining systems for deep hole drilling machines
Deep hole drilling machine is a high-precision, high-efficiency, high-automatic deep hole machining special machine. It relies on advanced hole machining technology (gun drill, BTA drill, spray drill, etc.) to achieve general drilling through one continuous drilling. Machining accuracy and surface roughness that can be achieved by drilling, expanding, and reaming processes. Machining hole diameter dimensional accuracy: IT7 ~ IT11; processing hole skewness: ≤ 0.5 ~ 1 / 1000 (machined hole depth); processing hole surface finish: Ra 0.2 ~ 6.3um.
Deep analysis of 3 machining systems for deep hole drilling machines
Deep hole drilling machine processing system:
1. Gun drilling system
It is mainly used for drilling of small diameter (generally less than 35mm) deep holes, and the required cutting fluid pressure is high. It is the most common deep hole drilling method. It belongs to the method of internal cooling and external chip removal. The cutting fluid passes through the inside of the hollow drill pipe, reaches the drill head for cooling lubrication, and discharges the chips from the drill bit and the V-shaped groove outside the drill pipe. The Jinshi QYZ deep hole drilling system suitable for small and medium batches also belongs to the gun drilling processing system. It can be conveniently arranged on ordinary machine tools such as lathes, boring machines and machining centers. Its tools use gun drills and high pressure aerosols provide cooling and The power of chip removal.
2, BTA single pipe drilling system
It belongs to the method of chip removal in the outer cold. The cutting fluid enters from the outer wall of the drill pipe and the machined surface of the workpiece through the oil feeder, reaches the cutter head for cooling lubrication, and pushes the chip from the inside of the drill pipe. In addition to the guiding function, the oil feeder provides a passage for oil to the cutting zone. The system is widely used, but it is limited by the chip evacuation space of the drill pipe. It is mainly used for deep hole drilling with diameter ￠>12mm. The high cutting fluid pressure makes the single pipe drilling system more reliable than the suction drill, especially when drilling materials that are difficult to break (such as mild steel and stainless steel). Compared to spray drills, the BTA single pipe drilling system is the first choice for high volume, high load continuous processing.
3, spray suction system
Deep hole drilling in the system. The cutting fluid enters through the oil inlet of the coupling, and most of the cutting fluid enters the annular space between the inner and outer drill rods, reaches the cutter head for cooling lubrication, and pushes the chips into the inner bore of the inner drill rod to discharge backward. In addition, a small part of the cutting fluid utilizes the jet effect of hydrodynamics, and the high-pressure jet of the crescent nozzle on the inner drill pipe is injected into the rear part of the inner drill pipe to form a low pressure zone in the inner cavity of the inner drill pipe, and the cutting of the cutting zone is performed. The liquid and the chips produce a rearward suction, which promotes the rapid outward discharge of the chips under the dual action of pushing and sucking. This relatively independent system requires less cutting fluid pressure than the BTA system, while also reducing the sealing requirements of the drilling system. Due to the inner tube, the minimum diameter range of the jet drilling process is limited, generally not less than ￠18mm.