摘要 |
<p>A pressure relief valve has a valve disc with a valve stem extending through a valve opening and an annular sealing washer disposed between the disc and a valve seat about the valve opening operated by a limitedly flexible, spring loaded, longitudinally ribbed, holding element with a conically tapering central aperture through a central hub thereof through which the valve stem extends to dispose an enlarged valve stem head behind a hub shoulder.</p> |