| 摘要 |
<p>An annular seal for pipework joints subject to wide operating temp. variations and/or thermal shock comprises a metal body with each axial face relieved except for the internal border. Annular spacers or linings of a stiff, elastic refractory material are fitted on to each face and have a thickness greater than the depth of the axial relief by an amt. which can be eliminated by compression due to the clamping pressure to be used to hold the composite seal in place. Esp. for use in e.g. steam distribution systems, etc. The reaction of the elastic linings maintains an interfacial seal. The core surface of the annular body eliminates direct contact between the pipe contents and the compressible seal material. Pref. the linings are of expanded graphite or of a thermosetting resin filled with fibres of 'Monel' (RTM- alloy involving Mo and Ni) silicaeous alumina or (high m.pt.) polyamide.</p> |
