| 摘要 |
<p>PCT No. PCT/FI81/00007 Sec. 371 Date Sep. 24, 1981 Sec. 102(e) Date Sep. 24, 1981 PCT Filed Jan. 29, 1981 PCT Pub. No. WO81/02119 PCT Pub. Date Aug. 6, 1981.A flange forming drill means for drilling a hole through the side of a pipe or the like and forming a hole encircling flange includes a drill rod mountable on a rotating power source with a drill bit at the lower end and associated retractable flange forming members which are extendable down below the edges of a drilled hole by turning an adjustment cone mounted on the drill rod. The adjustment cone is enclosed and keyed to an externally smooth, protective shield selectively securable to a locking ring on the drill at a plurality of relative angular positions around the drilling axis. The locking flange includes a circumferentially extending groove provided with holes or recesses at opposite ends defining terminal positions of locking so that in a first terminal locking position, the forming members are retracted completely within the outer surface of the drill bit and in a second terminal locking position the forming members extend or project outwardly from the drill bit for forming a flange around the drilled hole of a desired internal diameter as the drill bit is moved outwardly from the pipe.</p> |
