| 摘要 |
<p>982,873. Valves; lined conduits; junction pieces. GRINNELL CORPORATION. April 17, 1962 [April 21, 1961; June 8, 1961], No. 14799/62. Headings F2G, F2P and F2V. A method of forming a lined pressure conduit, such as a diaphragm valve housing 12 or a pipe elbow 40, comprises locating a liner 26 in the conduit and introducing incompressible material into gaps 28, 30 between the liner exterior surface and the housing interior surface whereby the liner will be supported by the material in the area of the gaps. The liner may be moulded in situ or be preformed to smaller dimensions than the interior of the housing to prevent crushing when the latter is assembled from half sections connected by transverse bolts. The liner may be of poly-. vinylchloride, polytetrafluoroethylene, which may be reinforced with 2% by weight of glass fibres, or of materials known by the Registered Trade Marks " Penton " and " Saran," while the material used to fill the gaps may be six parts by volume of a preparation known by the Trade name Smooth-On, mixed with one part of water and injected through openings 36, 37 at room temperature under a pressure of about 40 p.s.i.</p> |
