| 摘要 |
<p>A method of tightening a special joint having a screwless metal sealing surface and a screwless shoulder part, comprising the steps of setting the ratio of a shoulderng torque at the time of impactive contact on the screwless shoulder part to a tightening torque at the time of completion of tightening at 1.25 to 20 and, desirably, controlling the ratio at 1.4 to 10, whereby a sufficient airtightness can be assured without being affected by the type and use condition of the pipe joint, an elastic deformation due to an excessive tightening can be prevented and, even in the present state where the environment of an oil well becomes severe, the pipe joint can be used widely for tightening the special joint used for an oil well pipe.</p> |
