# US 2013/0152357 A1 · Test arrangement for a centrifugal compressor stage > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0152357 A1 - Document ID: US20130152357A1 - Status: Published application - Kind: A1 - Application number: 13/719,329 - Filed: 2012-12-19 - Published: 2013-06-20 - Earliest claimed: 2011-12-20 - Assignees: Nuovo Pignone S.p.A. - Inventors: Alberto Scotti Del Greco; Libero Tapinassi; Stefano Vanghi; Filippo Gerbi; Chiara Cinelli - Web page: https://patentgrep.com/patent/US20130152357A1 ## CPC - F04B 51/00: Testing machines, pumps, or pumping installations - F04D 27/001: {Testing thereof; Determination or simulation of flow characteristics; Stall or surge detection, e.g. condition monitoring} - Y10T 29/49764: with testing or indicating - F04B: POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS (machines for liquids, or pumps, of rotary-piston or oscillating-piston type F04C; non-positive-displacement pumps F04D; pumping of fluid by direct contact of another fluid or by using inertia of fluid to be pumped F04F) - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A system for testing a compressor is provided. The system comprises one or more compressors connected together in series to a test compressor wherein an output of the test compressor is connected to an input of a first compressor in the series, forming an overall loop, one or more process fluid coolers in the overall loop, one or more orifices in the overall loop, a control valve in the overall loop, and a first plurality of sensors configured adjacent to a process fluid input of the test compressor and a second plurality of sensors configured adjacent to a process fluid output of the test compressor. ## Claims ### Claim 1 A system for testing a compressor, the system comprising: one or more compressors connected together in series to a test compressor wherein an output of the test compressor is connected to an input of a first compressor in the series, forming an overall loop; one or more process fluid coolers in the overall loop; one or more orifices in the overall loop; a control valve in the overall loop; and a first plurality of sensors configured adjacent to a process fluid input of the test compressor and a second plurality of sensors configured adjacent to a process fluid output of the test compressor. ### Claim 2 (depends on 1) The system of claim 1, wherein the test compressor is a centrifugal compressor. ### Claim 3 (depends on 2) The system of claim 2, wherein the one or more compressors are centrifugal compressors. ### Claim 4 (depends on 1) The system of claim 1, wherein the one or more compressors have a cumulative output capacity greater than the test compressor. ### Claim 5 (depends on 4) The system of claim 4, wherein the cumulative output capacity is sufficient to overcome head value losses associated with the overall loop. ### Claim 6 (depends on 5) The system of claim 5, wherein the testing is associated with generating a test compressor performance curve based on non-extrapolated empirical data for the test compressor at head values lower than the head value losses associated with operating conditions of the overall loop. ### Claim 7 (depends on 1) The system of claim 1, further comprising connecting a separate motor and gear box to each of the one or more compressors and to the test compressor. ### Claim 8 (depends on 1) The system of claim 1, further comprising a plurality of valves configured in the overall loop such that each of the compressors and the test compressor can be isolated and operate as an independent test loop. ### Claim 9 A method for obtaining non-extrapolated empirical data associated with performance characteristics of a compressor at head values lower than head value losses associated with a test loop connected to the compressor, the method comprising: connecting an auxiliary compressor to a main compressor in a test loop such that a process fluid output from the auxiliary compressor is connected to a process fluid input of the main compressor and a process fluid output from the main compressor is connected to a process fluid input of the auxiliary compressor; installing a control valve in the test loop between the auxiliary compressor and the main compressor; installing one or more process fluid coolers and one or more orifices in the test loop between the auxiliary compressor and the main compressor; installing a first plurality of sensors in the test loop adjacent to the process fluid input of the main compressor; installing a second plurality of sensors in the test loop adjacent to the process fluid output of the main compressor; and collecting data from the first plurality of sensors and the second plurality of sensors while operating the test loop at conditions such that the main compressor head is lower than head value losses associated with the test loop. ### Claim 10 (depends on 9) A method for sizing an electric motor associated with a single or multistage compressor, for optimally meeting the compressor startup requirements, the method comprising: obtaining, using the method of claim 9, non-extrapolated empirical data for each stage of the compressor; calculating an overall performance map of the compressor using the non-extrapolated empirical data for each stage of the compressor; and calculating the absorbed power of the compressor at startup using the overall performance map of the compressor to size the electric motor.