The author put forward a new kind of collar called tensioned collar, which includes an up collar and a down collar, they are connected each other with screw, there are cylinder and spring in them.

• 提出了受拉钻铤的结构，它包括上、下两个钻铤，它们之间通过丝扣连接在一起，内部有内筒和弹簧。这种结构，当将下钻铤和上钻铤拧在一起并紧扣时，会使下钻铤和上钻铤受到拉力。