GB316353A - Improvements in and relating to surface coatings of ebonite, hard rubber or the like - Google Patents

Abstract

316,353. Menzel, H. r. W. May 1, 1928. Grant of Patent refused. Moulding indiarubber, hollow-ware, pipes and tubes.-A process for lining tubes, pans, &c. with ebonite, hard rubber, &c. consists in introducing a perforated hollow core covered wtih a continuous layer of the lining material, exhausting the air between the article and the core, and then inflating the material to transfer it to the inner surface of the article, on which it is subsequently vulcanized. The layer of material may be a calendered sheet with its edges joined or may be an extruded tube. In the apparatus shown in Fig. 1, the tube a to be lined is first treated with a layer of rubber solution and is mounted on carriages b running on rails d. The core k with the rubber sheet n is mounted at one end in a cap h and at the other end carries a pivoted roller d<1> which during passage of the tube over the core runs along the interior of the tube to prevent contact of the sheet n with the prepared surface. A second cap h<1> closes the other end of the tube a, both caps having airtight stuffing-box joints i, i<1>. During the assembling, the rubber sheet is retained on the core: by suction through a two-way valve m and when the core is in position suction is also applied to the space between the tube a and the core. Air is then admitted to the interior of the core causing the sheet n to be transferred to the interior of the tube a. After removal of the core the lined tube passes to the vulcanizing chamber which may be arranged in continuation of the rails d. A modified end-cap Fig. 3, comprises two hinged semi-circular sections h<1>, h<2>, locked together by a pivoted bolt, each section containing a rubber gasket s of channel-section engaging on one side the exterior of the core and on the other side the exterior of the tube to be lined. In lining a cylindrical pan, a cylindrical core corresponding to the shape of the pan 'is carried by a cover-plate which is secured to the flanged rim of the pan, the plate being provided with apertures communicating with the interior of the core and with the space between the core and the pan for connection to exhaust and supply pipes arranged as in Fig. 1.