| 摘要 |
The fitting comprises a wrench bar 4 having a cap accessible from above ground, a tube 5 surrounding the bar and a releasable coupling 3 for engaging a valve spindle. The bar may be extended by extensions, interconnection being via square sockets/releasable adaptors. Tube 5 may comprise telescopic sections 5a-d. Release of the coupling may be facilitated by a bolt having a head located in a blind bore in the sleeve and a threaded portion located in a threaded bore in the sleeve, the bolt extending through the wrench bar. Alternatively, release is facilitated by a pair of spring biassed pins or wedges. The pins may be located in a tube insertable into the wrench bar. The upper end of the bar may be coupled to a common unit (32, figure 11) which is connected to but free to rotate relative to the tube 5. |
