高强度钻铤螺纹的研制及应用

Development and application of high-strength drill collar threaded connection

在分析钻铤螺纹失效部位及原因的基础上，研制了高强度钻铤螺纹，它与普通钻铤螺纹相比，只是在外螺纹小端增加了一段光平的锥体。当钻铤上扣到规定扭矩时形成第二台肩，第二台肩和第一台肩同时顶紧，螺纹最小截面积可增加４３％，增加了螺纹承载能力。现场使用表明，使用高强度钻铤螺纹是延长钻铤寿命、减少井下事故的一种有效措施。

On the basis of an analysis of the location and causes of the failure of drill collar threaded connection, a high-strength drill collar threaded connection is developed. The difference between this threaded connection and the conventional drill collar threaded connection is a length of smooth and flat cone added on the pin end. When the drill collar is screwed to the given torque, a second shoulder is formed and works simultaneously with the first shoulder, so the load capacity of the threaded connection can be increased.