| 摘要 |
<p>The cup shaped barrel plug is of metal, with a cylindrical boss having an external thread, and an annular flage at the free end parallel to the bottom. An annular recess is formed between the end of the thread and the rear side of the flange, to accommodate a sealing ring, and inside there are protrusions with which a turning tool engages. The plug is a one-piece deep-drawn sheet metal stamping, with thread (4) formed by pressure from inside to outside. The protrusions (6) are formed in the boss portion (3) radially from outside to inside, and are wedge-shaped, the points of the wedges being diametrally opposite each other. Their height is the same as the length of the threaded portion.</p> |
