| 摘要 |
PCT No. PCT/GB83/00224 Sec. 371 Date May 11, 1984 Sec. 102(e) Date May 11, 1984 PCT Filed Sep. 12, 1983 PCT Pub. No. WO84/01120 PCT Pub. Date Mar. 29, 1984.Method of producing side-pocket mandrels free of welds comprising a series of boring and machining steps by mechanical action and/or electro-erosion to produce a mandrel having at least one valve pocket and discriminator. |
