在车床上实行高速切削时,除了硬质合金刀具以外,最基本的工具就是活顶针,因为一般工作物(尤其是长的)在车床上切削,必需用尾架顶针顶著,而尾架的顶针是死的,不能随工作物转动,倘若转速过高时,工作物的顶针眼(中心孔)就会与顶针尖发生很厉害的磨擦,因此顶针尖要磨机,甚至因高热 In the implementation of high-speed cutting lathe, in addition to carbide cutting tools, the most basic tool is live thimble, because the general work (especially long) in the lathe cutting, the need to use tailstock thimble, while the tailstock Thimble is dead, can not rotate with the work material, if the speed is too high, the work of the thimble eye (center hole) and the top needle tip will be very powerful friction, so the top needle to mill, and even because of high fever