先钻孔然后攻螺纹是机械工厂中常见的一种加工方法。如在钻床的立柱上附加一套手动攻螺纹装置,就能避免频繁地调换钻头和丝锥。该装置是一附加横臂,由其下面的销紧圈将其紧固。钻床工作台的紧固方式与此相同。如图所示,在横臂的内侧端装上一块铣有V 型槽的金属板,此板与立柱相配,以保证横臂和立柱的垂直度。在横臂的外侧端焊上一套筒,立柱和套筒的中心距应和立柱 Drilling holes first and then taping is a common machining method in machine shops. Adding a set of manual tapping devices to the column of a drilling machine will prevent frequent drill bits and tap changes. The device is an additional cross arm, which is fastened by the pin collar below it. The drilling table is fastened in the same way. As shown in the figure, a metal plate milled with V-shaped grooves is attached to the inner end of the cross arm. The plate is matched with the column to ensure the perpendicularity of the cross arm and the column. Welding a sleeve on the outer side of the cross arm, the center distance between the column and the sleeve should be and column