我厂生产的柴油机油箱放油座(图1),要求保证连接处不漏油。因此,对螺纹的垂直度要求较高(相对于端面),允许公差≤0.1mm。过去,我们采用车削加工,车端面、钻孔、套丝,再用人工扳丝,工人劳动强度大,丝锥耗损量大。为此,我们设计了一种攻丝夹具(图2)。该夹具用支承2把底座1和导板8连接成一个固定架。丝锥夹头12和丝套9的螺纹,应配作成与丝锥相同的螺距,装入导板8中,再装上压缩弹簧7和压件圈4,并用螺钉6固定丝锥和连接压件 I plant the diesel tank oil tank seat (Figure 1), required to ensure that the joints do not leak oil. Therefore, the thread of the vertical requirements (relative to the end face), allowing tolerance ≤ 0.1mm. In the past, we used turning, car face, drilling, threading, re-use of artificial wire, workers labor-intensive, tap consumption. To this end, we designed a tapping fixture (Figure 2). The holder 2 supports the base 1 and the guide plate 8 as a fixed frame. Tap chuck 12 and the thread 9 of the sleeve 9 should be made with the same thread pitch, into the guide plate 8, and then loaded on the compression spring 7 and the pressure ring 4, and with a screw 6 taps and connecting pieces