在配管操作中,有的管工用普通角尺靠正,往往是管了前后,管不了左右(图1)。有的管工用水平尺靠正(图2),得先使主管或工作台水平,而且靠了前后,待靠左右时,鎯头一敲,前后又跑动了,效率很慢。现在介绍一种V形角尺(图3)。用这种角尺对支管,能够一次成活。使用时,操作者右手将尺压在主管上,左手拿短管贴紧 In the piping operation, some pipe workers rely on the square, which is usually the front and rear pipes, and cannot be controlled (Figure 1). Some of the foremen are using a horizontal ruler to reach the front (Figure 2). The supervisor or the workbench must be leveled first, and before and after leaning against the front and back, the hammers are knocked and run back and forth. The efficiency is very slow. Now introduce a V-shaped square (Figure 3). With this square, the branch can survive once. In use, the operator presses the ruler on the main pipe with his right hand and the short pipe with his left hand