摘要 |
A threaded tube joint structure for casing, particularly oil well tubing, which is more perfect in the sealing performance than any other joint. This sealing performance is obtained with a first metal-to-metal contact seal between the outer surface of a lip of a male threaded member and a corresponding inner surface of a female threaded member and a second metal-to-metal contact seal between the end face of the lip and a corresponding face of the female threaded member. This structure permits the realization of the intended alignment of the reference axes of the abutting faces of the second seal because these faces resist deviation from their fixed positions relative to each other. |