Mounting of pressure relief devices in a high pressure refrigeration system

Abstract

A plurality of pressure relief devices are disposed within a refrigeration circuit, and each of the pressure relief devices is located within a compartment that fluidly communicates with the ambient air. Each of the pressure relief devices is oriented so that the release of high pressure vapor therefrom is directed to a rear wall of the compartment. Further, a four sided cover is disposed over each of the pressure relief devices so as to partially contain any released vapor and allow it to be discharged in one direction only.

1 . A vapor compression system comprising:
 a refrigerant circuit having in serial flow relationship; a compressor for compressing CO 2  vapor as a refrigerant, a heat rejecting heat exchanger, an expansion device, and a heat absorbing heat exchanger disposed in heat exchange relationship with air flowing from a container to be refrigerated;   at least one pressure relief device disposed in said refrigerant circuit for relieving pressure therein when it exceeds a predetermined level, said at least one pressure relief device being located in a compartment which fluidly communicates with ambient air.   
     
     
         2 . A vapor compression system as set forth in  claim 1  wherein said compartment includes upper and lower walls, side walls, and a rear wall, and further wherein said least one pressure relief device is mounted to said rear wall. 
     
     
         3 . A vapor compression system as set forth in  claim 2  wherein said at least one pressure relief device is so orientated that when refrigerant vapor is released therefrom, it is directed toward said rear wall. 
     
     
         4 . A vapor compression system as set forth in  claim 2  wherein said at least one pressure relief device is surrounded on four sides by a cover, with only a bottom portion of said cover being open to the flow of vapor therefrom. 
     
     
         5 . A vapor compression system as set forth in  claim 4  wherein said cover is attached to said back wall. 
     
     
         6 . A vapor compression system as set forth in  claim 1  wherein said at least one pressure relief device is disposed near a suction inlet of a compressor. 
     
     
         7 . A vapor compression system as set forth in  claim 1  wherein said at least one pressure relief device comprises a rupture disc. 
     
     
         8 . A vapor compression system as set forth in  claim 1  wherein said at least one pressure relief device comprises a pressure relief valve. 
     
     
         9 . A vapor compression system as set forth in  claim 1  wherein said refrigeration circuit includes an unloading circuit with a valve, and further wherein said at least one pressure relief device is disposed between said valve and an intermediate stage of the compressor. 
     
     
         10 . A vapor compression system as set forth in  claim 9  wherein said valve is a normally closed valve. 
     
     
         11 . A vapor compression system as set forth in  claim 1  wherein said at least one pressure relief device includes three pressure relief devices with all three being located in said compartment.