GB619276A - Improvements in pressure-balanced pipe expansion joints - Google Patents

Abstract

619,276. Pipe joints. METALLSCHLAUCHFABRIK AKT.-GES. Nov. 29, 1946, No. 35455. Convention date, Dec. 7, 1945. [Class 99 (i)] A pressure-balanced pipe expansion joint comprises a main corrugated tube 1 of approximately the same internal diameter as the pipeline and a number of pressure balancing corrugated tubes 13 disposed around the main tube and equal in total area to the area of the main tube, the balancing-tubes being arranged so that they are shortened when the main tube is extended and vice versa. The tube 1 terminates in cylindrical portions with beaded ends gripped between an upper pair of flanges 4, 5 and a lower pair of flanges 4<1>, 51. The ends 2, 21 are located between tubular extensions 9, 9<1> of the flanges 4, 4<1> and rings 10, 10<1>. A thin tube 11 is welded or riveted to the part 9<1>. The smaller tubes 13 are closed by end plates 14, 14<1> and an inner guide tube 16 limits the contraction of the corrugated tubes. The end-plates are secured to flange rings 18, 18<1>. Four bolts 21 are secured to plate 18 and end flanges 41, 5<1> slide in the flanges 4, 5 while alternate bolts 22 are secured to lower plate 18<1> and flanges 4, 5 and slide in the flanges 4<1>, 5<1>. A pipe 26 connected to the main pipe-line communicate with the balancing-tubes through ring 24 and lines 23. When the tube 1 contracts, the tie-rod connections cause extension of the balancing- tubes, the movement being limited by contact of the flanges 5, 5<1> with the rings 18, 181 respectively. Conversely expansion of the tube 1 causes contraction of the balancing-tubes which is limited by the engagement of guides 16 with the plates 14. The number of balancing-tubes may be varied with corresponding variation in their diameters. In some cases separate lines 26 may lead from the main pipeline to each of the tubes 13.