| 摘要 |
A cable-operated jar comprising a releasable coupling is arranged for connection to a piece of downhole equipment, in which a mandrel is connected to a cable comprising a hammer section. The hammer section is arranged to strike, on the release of a mandrel coupling, against a shoulder section in a housing, and the mandrel is pre-tensioned in a releasable position with a spring arrangement. The spring arrangement includes an adjusting, mechanism operated by the cable alternately being tensioned and relaxed. |
| 主权项 |
1. A cable-operated jar (2) provided with a releasable coupling (22) arranged for connection to a piece of downhole equipment (1), in which a mandrel (23), which is connected to a cable (3), is provided with a hammer section (2322) which is arranged to strike, on the release of a mandrel coupling (234), against a shoulder section (212) in a housing (21), and the mandrel (23) is pre-tensioned in a releasable position by means of a spring arrangement (24) including an adjusting mechanism (25) operated by alternately tensioning and relieving the cable (3), characterized in that the adjusting mechanism (25) includes an adjusting sleeve (251) which is axially displaceable along a portion of a lower mandrel section (231) between a change-over abutment (S0) and different work abutments (S1, S2, . . . , Sn). |
