Spiral tensioners are widely used in shipbuilding to tighten steel plates during the welding process to keep the plates in place, which is a desirable result for welding steel plates. The Chinese patent discloses a picture of an improved tensioner tensioner (Grant Notice No. CN 201082765Y), which includes a body having a rotatable shaft and a handle attached to the shaft, and the handle is provided between the handle and the shaft. The tightening mechanism that can be done for one-way rotation of the shaft has an ankle strap connected to the shaft, and the outer end of the strap is provided with a hook, and the hook is also connected to the main body, and the hook includes a buckle and a hook body, and the buckle and the hook body have a connection mechanism for rotating the hook body relative to the buckle, and the buckle is connected to the outer end of the above-mentioned strap, and the hook 2 includes the buckle and the hook body, and the main body is provided with a link and a link between the hook 2. One end is hinged to the body, the other end of the connecting rod is connected to the buckle, and the hook is connected to the hook body. Arranged so that the hook body relative to the ring belt buckle rotating connection mechanism