| 摘要 |
<p>A valve, for example for use as a pipeline stop valve or a blow-out preventer, comprises a body with a central passage and opposed aligned guideways extending outwards from the passage. A closure member is provided in each guideway, each of which guideways is closed by a bonnet housing moving means for the respective closure member. The moving means are adapted to move each closure member through the central passage and into the opposite guideway, the closure members sealing therein to enable the opposite bonnet and associated closure member to be removed for a servicing operation.</p> |
