System disconnector

Abstract

A system disconnector ( 10 ) for physically disconnecting an upstream liquid system from a downstream liquid system by means of an outlet valve ( 48 ) provided in a housing ( 16 ), the disconnecting being effected depending on the pressure drop between the upstream and the downstream liquid system, and wherein the housing ( 16 ) is provided with a bore ( 28 ) and an opening ( 26 ) in alignment with said bore ( 28 ), said opening adapted to be closed, includes a pressure reducer ( 66, 36 ) in the form of a cartridge provided in said bore ( 28 ), which is adapted to be removed in one piece from the housing ( 16 ). The system disconnector ( 10 ) is provided with an upstream backflow preventer ( 40 ), a downstream backflow preventer ( 42 ), and an outlet valve body in the form of a piston ( 44 ) biased by a spring, said outlet valve body disposed between said backflow preventers, wherein the pressure reducer cartridge ( 34, 36 ), the backflow preventers ( 40, 42 ), and the outlet valve body ( 44 ) are disposed in alignment inside the bore ( 28 ).

1 . A system disconnector ( 10 ) for physically disconnecting an upstream liquid system from a downstream liquid system by means of an outlet valve ( 48 ) provided in a housing ( 16 ) said disconnecting being effected depending on a pressure drop between said upstream and said downstream liquid system wherein said housing ( 16 ) is provided with an inlet ( 12 ), an outlet ( 14 ), a bore ( 28 ) and an opening ( 26 ) in alignment with said bore ( 28 ), said opening adapted to be closed and in that a pressure reducer ( 66 ,  36 ) in the form of a cartridge is provided in said bore ( 28 ), which is adapted to be removed in one piece from said housing ( 16 ). 
   
   
       2 . A system disconnector ( 10 ) according to  claim 1 , wherein said system disconnector is provided with an upstream backflow preventer ( 40 ), a downstream backflow preventer ( 42 ) and an outlet valve body in the form of a piston ( 44 ) biased by a spring, and wherein said outlet valve body is disposed between said backflow preventers and wherein said pressure reducer cartridge ( 34 ,  36 ) said backflow preveters ( 40 ,  42 ) and said outlet valve body ( 44 ) are disposed in alignment inside said bore ( 28 ). 
   
   
       3 . A system disconnector according to  claim 2 , wherein
 (a) said pressure reducer is provided with a helical spring ( 60 ), a lifting member, a fixed valve disc ( 66 ) and a valve seat body ( 36 ) cooperating with said fixed valve disc ( 66 ) thereby defining a closing and an opening direction, said valve seat body being adjustable by said lifting member exposed to an outlet pressure in said closing direction against the effect of said helical spring ( 60 ),   (b) a valve spindle ( 62 ) is provided, said valve spindle having an axial bore ( 64 ); and wherein said valve seat body ( 36 ) is slidably guided on said valve spindle ( 62 ) connected to said valve disc ( 66 ) with an axial bore ( 64 ), and   (c) said outlet of said downstream backflow preventer ( 42 ) ends in said axial bore ( 64 ) in said valve spindle ( 62 ) and said bore ( 64 ) is connected to said space upstream of said valve seat.   
   
   
       4 . A system disconnector ( 10 ) according to  claim 3 , wherein said valve spindle ( 10 ) is integrated in a cartridge housing ( 34 ) which is adapted to be inserted into said bore ( 28 ) up to a stop ( 52 ) and said downstream backflow preventer ( 42 ) is adapted to be inserted into said cartridge housing ( 34 ). 
   
   
       5 . A system disconnector ( 10 ) according to  claim 4 , wherein said valve spindle ( 62 ) is provided with a valve disc ( 66 ) at its downstream end, said valve disc extending into an inner space of said pot-shaped valve seat body ( 36 ), and wherein said valve spindle ( 62 ) is provided with a thickened portion ( 72 ) in a radial direction in a range of said inner space ( 74 ) of said valve seat body ( 36 ), said thickened portion ( 36 ) serving as a dog for removing said cartridge housing ( 34 ) from said bore ( 28 ). 
   
   
       6 . A system disconnector ( 10 ) according to  claim 1 , wherein test sockets ( 20 ,  22 ,  24 ) are provided enabling a pressure control at said inlet ( 12 ), at said outlet ( 14 ) and in said medium pressure chamber ( 38 ) between said backflow preventers ( 40 ,  42 ) of said system disconnector.