What is the introduction of deep hole drilling?

Deep hole drilling is a highly specialized hole processing technology. General special deep-hole tools (such as gun drill, internal chip removal deep-hole drill, nesting drill, etc.). ) and need special machine tools for processing, need a lot of circulating cutting oil to remove chips, cooling and lubricating tools. The high consumption of cutting oil will not only increase the processing cost, but also cause oil pollution on the processing site, threatening the health of operators. At the same time, the treatment of oily iron filings will cause air and environmental pollution. Therefore, realizing dry machining without cutting fluid or sub-dry machining with micro cutting fluid is one of the development directions of deep hole machining technology.

Deep hole drilling is a hole processing technology with high technical content, strong professionalism and high processing cost. Generally, only production units with high degree of specialization and strong technical force have the processing capacity in this respect. Because deep-hole parts are widely used in petroleum, aviation, military industry, construction machinery and other industries, such large-scale production units generally have large-scale deep-hole processing workshops, and the annual production batch and output value are very large. Deep hole machining technology is different from the traditional twist drill drilling method. General special deep-hole drill (such as gun drill, internal chip removal deep-hole drill, nesting drill, etc.). ), using special machine tools and complex accessories to complete deep hole processing. In machining, a large amount of circulating cutting fluid (such as special deep-hole cutting oil (liquid) or engine oil) is used to remove chips, cool and lubricate tools, and the consumption of cutting fluid is large (mainly taken away by chips). It threatens the health of operators, and the treatment of oily iron filings will cause secondary pollution of air and environment and increase manufacturing costs. Therefore, how to reduce the processing cost and eliminate environmental pollution is an important development direction of deep hole processing technology research. If dry machining technology can be applied to deep hole machining, the above problems will be well solved.

Due to the special requirements of deep hole machining, it is difficult to achieve complete dry cutting (that is, no cutting fluid is used at all) in actual production, because in deep hole machining, the tool works by the self-guiding function of the guide block, and great friction will be generated between the guide block and the hole wall due to mutual extrusion. In the traditional wet deep hole machining, high-pressure cutting oil will form an oil film between the guide block and the hole wall, which will play a lubricating role in the machining process and reduce friction. If there is no oil film, the guide block will wear and tear quickly, causing cutting vibration or cutting. In addition, deep hole machining is carried out in a closed space, and the chip removal channel of the tool is long, so the cutting heat generated during machining is much greater than that of ordinary turning, and unlike ordinary dry turning, the heat dissipation can be accelerated by increasing the cutting speed (which will lead to chip removal failure and sharp tool wear). Therefore, it is the most feasible research idea to use sub-dry method for deep hole machining. During machining, compressed air is used to drive micro cutting fluid, which is mixed and atomized, then transported to the cutting area through the channel between the hole wall and the drill pipe, and sprayed to the chip contact area at high speed, giving full play to the cooling and lubricating functions of the cutting fluid, and at the same time, high-speed compressed air helps to discharge iron chips, thus completing the production process. In the process of machining, the cutting fluid is almost completely absorbed between the guide block and the hole wall and the contact area of the tool chip, which gives full play to the role of cooling fluid. Saving the use of cooling oil (liquid) and putting an end to environmental pollution are in line with the current strategic policy of sustainable national economic development and have certain practical significance. Economically speaking, it can save a lot of manufacturing costs, and its social benefits (reducing environmental pollution and health hazards to operators) will be more significant.