摘要 |
A threaded metal sleeve includes a core and a thread provided on the outside of the core, with the thread profile having a flank angle within the range from 25° to 35°. The pitch (h) of the thread is 0.1-fold to 0.4-fold of the outer diameter of the threaded sleeve, and the thread depth of the thread is 0.02-fold to 0.2-fold of the outer diameter of the threaded sleeve. |