在加工某液压阀内孔时，其径向槽尺寸公差要求较高，按常规测量方法很难达到要求，为此我们自制了一种槽径量具（图1），其结构和使用方法如下：t量具的主体由铰接相连的上体8和下体3组成，百分表1插入表座4中，藉紧固螺钉2固定。表座4用螺钉固定在下体3上，测头6与测量座7的上 In the processing of a hydraulic valve bore, the radial groove size tolerance requirements, according to conventional measurement methods is difficult to meet the requirements, for which we have made a self-measuring groove diameter (Figure 1), the structure and use as follows: t The main body of the measuring instrument is composed of an upper body 8 and a lower body 3 which are hingedly connected, and the dial indicator 1 is inserted into the table seat 4 and is fixed by a fastening screw 2. The table base 4 is fixed on the lower body 3 with a screw, and the upper part of the measuring head 6 and the measuring base 7