深微锥孔汽蚀管加工工艺研究

Machining technology research of cavitating venturi with deep tapered micro-hole

为了实现深微锥孔汽蚀管的精密机械加工,研究了汽蚀管收敛段与喉部精密车镗加工、Ф0.65通孔钻孔加工以及6°锥孔铣铰加工工艺。针对6°锥孔的铣铰加工,定制了京瓷6°锥铣刀和6°锥铰刀,刀具材料为高强度亚微粒碳化钨,刀具表面涂层为高硬度纳米复合结构涂层,刀具结构为能抑制振动并增加刃口强度的特殊结构。得出了深微锥孔汽蚀管最佳工艺规范。采用该工艺规范加工生产的汽蚀管内表面表面粗糙度为Ra 0.4,满足设计要求;采用该工艺规范加工生产的汽蚀管通过了液流试验,试验结果满足设计要求;装配有采用该工艺规范加工生产的汽蚀管的发动机已经通过了地面热试车考核。

The precision machining technology of cavitating venturi with deep tapered micro-hole is introduced in this paper. In order to realize precision machining of the cavitating venturi with deep tapered micro-hole, the precision lathing-boring machining of convergent section and throat of cavitating venturi, drilling of Ф0.65 through-hole, and milling and reaming of 6° tapered hole were studied. Kyocera 6° tapered milling cutter and 6° tapered reamer were customized for the milling and reaming of 6° tapered holes. Both the cutter and reamer are made of high strength submicron tungsten carbide, and coated with high hardness nano-composite structure coating. The special structure of the two tools could eliminate vibration and increase the intensity of cutting edge. The optimal process specifications of cavitating venturi with deep tapered micro-hole machining were obtained. The cavitating venturi made with the optimal process specifications can satisfy the design requirements,whose inner surface roughness is Ra0.4. It has passed the liquid flow test. The engine with the cavitating venturi was verified in the ground hot firing test.