Exhaust casing assembly used for test piece of gas compressor

An exhaust casing assembly used for a test piece of a gas compressor comprises an outlet casing assembly, a front exhaust outer ring section, a front exhaust inner ring section, a test lead, an exhaust casing connecting ring, a rear exhaust outer ring section, a rear exhaust inner ring section and a balancing disc sealing ring. The whole casing assembly is formed through assembly of the exhaust casing connecting ring. The front end of the outlet casing assembly is connected with an outlet of the gas compressor. The rear end of the rear exhaust outer ring section is connected with a rear exhaust section of the test piece of the gas compressor. The outlet casing assembly and the rear exhaust outer ring section are connected with a front component and a rear component in an overlapped mode. The outlet casing assembly, the front exhaust inner ring section, the rear exhaust outer ring section and the rear exhaust inner ring section are of cantilever structures. The exhaust casing assembly has the advantages that the exhaust casing assembly is applied to the test piece of the gas compressor which is high in pressure ratio and large is flow, the requirements for balanced axial force, exhaust flow pass switching and the like of the test piece of the gas compressor are met, and meanwhile the relative requirements for testability, assembling capacity, reliability, maintainability and the like of the test piece can also be met.