| 摘要 |
A method of fabricating a coupling member having a U-shaped channel comprises the first step of boring one of upwardly open opposite passageways, a communication passageway and an auxiliary passageway in a blocklike body, the second step of inserting a closure member into the auxiliary passageway, the third step of welding the closure member to the inner peripheral body portion defining the auxiliary passageway, and the fourth step of boring the other upwardly open passageway in the blocklike body. The closure member is inserted in the second step so as to be positioned at least partly in the portion where the other upwardly open passageway is to be formed. <IMAGE> |
