摘要 |
A connector, for example for connecting a tubular member such as a pipe, comprises a male member which has an external frusto-conical surface provided with a thread and a female member having an internal frusto-conical surface provided with a thread for engagement will the thread of the male member. The members are provided with generally radially directed sealing surfaces which are brought into sealing abutment under an axially directed compressive force when the members are fully engaged together. To improve the loading of the threads of the members on engagement of the members and on application of a tensile load to the engaged members, the axial thickness of the thread of at least one of the members in one or both of the portions of the thread adjacent the ends thereof is reduced to increase the flexibility of the thread and therefore reduce the load sustaining ability of the thread. Specifically the reduction in the axial thickness is greatest at the end of the thread and progressively decreases away from the end. This reduction is achieved by providing threads having leading flanks with a constant pitch and trailing flanks whose pitches are varied to provide the required variation in axial thickness. In the preferred embodiment, the thread of the male member adjacent its free end is reduced in axial thickness and the thread of the female member adjacent its free end is reduced in axial thickness. |