Dispositif de raccordement et obturation entre deux tronçons d'une ligne de transfert de gaz liquéfié

1,063,769. Pipe-line closures; pipe Joints. COMMISSARIAT A L'ENERGIE ATOMIQUE. Nov. 4, 1965 [Nov. 19, 1964], No. 46802/65. Headings F2G and F2P. Means for sealing off the connection between the inner tubes of two coupled pipe sections A and B, each section comprising arcuate inner and outer tubes 2, 16 and 1, 18 respectively having a sealed annular space therebetween, comprises a conical plug C carried by a control rod 48 passing through tubular terminal extension portions 27 and 29 of the section B at right-angles to the inner and outer tubes of said section, said valve being adapted to stop the flow of a liquefied gas from pipe 2 to pipe 16 on rotation of the control rod nut 55. Said plug is adapted to seat on an annular seal 41 which is clamped between rings 40 and 5 secured to the terminal portions of the inner tubes 2 and 16 when the sections are coupled together by a screwring 31. The arrangement is such that the sections may be uncoupled and annular seal when worn replaced without the evacuated annular space of either pipe section being destroyed. The innermost end of the inner pipe of section A is connected by ring 5 and a tubular sleeve 3 to one end of outer tube of said section whilst the outermost end of the inner pipe is connected to a sleeve 7 secured to the other end of the outer pipe by a bellows 11, which permits relative expansion between the inner and outer pipes whilst maintaining a vacuum therebetween. The tubular sleeve 3 is received in the terminal portion 27 of the tube 16 and is sealed thereto by compression of a sealing ring 33 when a further screw-ring 30 is tightened. Expansion bellows 50 and 52 disposed between the control rod and the terminal portion 27 of the inner tube of section B and between the control rod and the terminal portion 27 of the outer tube 29 of section B ensure the maintenance of the evacuated space 18 of said section.