GB568808A - Improvements in apparatus for impregnating articles under vacuum - Google Patents

Abstract

568,808. Impregnating articles under vacuum. GENERAL ENGINEERING CO. (RADCLIFFE), Ltd., TAYLOR, S., TILLS, J. W., LOVATT, J. B., and POTTS, F. C. Aug. 10, 1943, Nos. 12894/43, 13497/43, and 14709/44 (divided out of 568,816). [Class 140] [Also in Group XXVI] In apparatus for impregnating under vacuum articles such as condensers or transformers with oil, paraffin wax, or a mixture of rosin and oil, a pump disposed in one evacuable vessel is adapted to transmit impregnant to a second evacuable vessel, either one of said vessels being a conditioning and/or storage vessel and the other being an impregnator. An impregnating vessel 11 is mounted in vacuum-tight relation to an impregnaut storage and treatment vessel 12, the vessels being separately evacuable through connections 27, 28, and vessel 12 containing a pump 13 adapted to transmit liquid impregnant to a spray ring 25 in vessel 11, through pipes 16-20, and then either direct through valve 24, or through a filter 21 and valves 22, 23. A heat-exchange coil 47 in the vessel 12 may be heated or cooled by passage therethrough of steam or cold water, and the vessels have heating jackets 48, 49. In operation, both vessels are heated and the storage vessel 12 containing the impregnating liquid is evacuated while the lid 29 of vessel 11, which is empty, is removed for introduction of the articles to be treated. After replacing the lid 29 and evacuating vessel 1, the impregnating liquid is pumped by means of pump 13 into vessel 11 and rises to a level determined by an adjustable overflow pipe 38, 39. Liquid returning to the storage tank through the overflow pipe and valve 44 flows over heat-exchange coil 47. At the end of the treatment, drain valve 37 is opened, the pump is stopped, and the liquid returns by gravity to the storage vessel 12. Valves 37 and 44 are controlled, and pump 13 is driven, by means located outside the vessel 12. In a modified apparatus having separate storage and impregnating vessels, the storage and conditioning vessel contains two pumps which are used for transferring the liquid to the impregnating vessel, and also, as described in Specification 568,816, to enable the treatment liquid to be sprayed into the storage vessel for de-aeration, passed through the heat-exchanger for heating or cooling, filtered, drawn from a supply vessel, drawn from or supplied to the impregnating vessel, and put under pressure in that vessel. Specification 568,105, [Group XXVI], is referred to in the first two Provisional Specifications.