深孔加工前置射流孔负压抽屑装置优化设计

Optimized design of pre-jet hole negative pressure chip removal device in deep hole processing

为解决大长径比深孔加工排屑困难问题,在分析DF系统负压排屑作用机理基础上,建立负压射流模型。针对前分离区涡流现象导致的能量损耗,提出采用两级喷射方式,在前分离区位置增加射流孔,使部分射流油液通过该孔进入前分离区,减小前分离区不必要能量损耗,从而增大负压值,通过理论分析及Fluent仿真优化实验,证明射流孔位于主喷嘴前部1 mm,排布方式为周向12个,直径0. 3 mm时效果最好,前分离区域最小,负压区域最大,负压区压力值降减小低约25%,最大程度的降低了前分离区域能量损耗,增强了负压排屑能力。

In order to solve the problem that the large-length-diameter ratios deep-hole machining has difficulty to chip removal, the negative pressure jet model is established on the basis of analyzing the mechanism of DF system's negative pressure chip removal. To solve the energy loss caused by the eddy current phenomenon in the front separation zone, this paper adopts two-stage injection method. The pre-jet hole is added in the front separation zone so that part of the jet fluid enters the front separation zone through this holes,reducing unnecessary energy in the front separation zone, increasing the negative pressure value. Through theoretical analysis and Fluent simulation optimization experiments, the paper proved that the jet hole located in the front of the main nozzle 1mm , arranged 12 in the circumferential direction and had the 0. 4mm diameter has the best effect. The front separation area is the smallest, the negative pressure zone is the largest, and the pressure value in the negative pressure zone is reduced by about 25 %, which minimizes the energy loss in the front separation zone and enhances the negative pressure chip removal capability.