| 摘要 |
<p>PURPOSE: To define completion of a practical service life of a pre-set sleeve by providing an abrasive layer on an inner conical surface of the pre-set sleeve, and forming the abrasive layer in a different color from that of base material. CONSTITUTION: A pipe screw comprises a screw main body 1, a nut 2, a cutting ring 3 to be engaged between the nut 2 and the main body 1, and a pipe 4. The pre-set sleeves 12, 12a are fitted for stably fixing the cutting ring 3 onto the pipe 4, and securing air-tight connection. This pre-set sleeve corresponding to the screw main body 1, has a hole part 13 conically tapered from an end, and the hole part 13 is formed as an inner conical surface.</p> |
