| 摘要 |
A well packer, in particular for a bore hole pump, comprises a packer sleeve having a tapered external surface surrounded by a collet ring which has a tapered internal surface. The collet ring is of resilient material and can be stressed to a smaller diameter configuration in which two adjacent collet-holding fingers of a removable holding mechanism engage in two now closely spaced holes of the collet ring to hold the collet ring in engagement with the smaller diameter lower part of the tapered external surface of the packer sleeve. The collet-holding mechanism can be operated to rotate a cam link of the mechanism to withdraw a safety link and to retract the fingers radially inwardly to release the collet allowing it to spring radially outwardly against a well casing in which the packer sleeve and the collet ring have been positioned by lowering down the well casing. |
