| 摘要 |
<p>A valve comprises a valve stem 2 surrounded in part by a packing material 3, and compression means arranged to bring the packing material into sealing engagement with the valve stem. The compression means includes a spring assembly comprising resilient springs 21 enclosed within a housing member 22 having a closure member 23 slidably mounted within it. The housing member 22 and the closure member 23 are provided with engagement means 27,28 acting to retain the closure member 23 captive within the housing member 22. <IMAGE></p> |
