| 摘要 |
<p>A well packer, in particular for a bore hole pump, comprises a packer sleeve (54) having a tapered external surface surrounded by a collet ring (2) which has a tapered internal surface. The collet ring (2) is of resilient material and can be stressed to a smaller diameter configuration in which two adjacent collet-holding fingers (18) of a removable holding mechanism (50-51-52-53-55-56-60-63) engage in two now closely spaced holes of the collet ring (2) to hold the collet ring in engagement with the smaller diameter tower part of the tapered external surface of the packer sleeve (54). The collet-holding mechanism can be operated (by releasing a triggering weight (57) after release of a latch (55) by pulling line B) to rotate a cam link (50) of the mechanism to withdraw a safety link (51) and to retract the fingers (18) radially inwardly to release the collet, allowing it to spring radially outwardly against a well casing in which the packer sleeve (54) and the collet ring (2) have been positioned by lowering down the well casing.</p> |
