Methods and systems for diagnosing valve defects in reciprocating compressors

Abstract

A diagnostic system for use with a compressor. The diagnostic system may include a sensor configured to measure a vibration signal of a compressor cylinder; and a controller having a hardware processor and a machine-readable storage medium on which is stored instructions that cause the hardware processor to execute a diagnostic process. The diagnostic process may include the steps of: storing a signature vibration data; receiving a sample vibration data from the sensor, wherein the sample vibration data is representative of the vibration signal measured by the sensor; comparing the sample vibration data to the signature vibration data to determine a similarity therebetween; and based on the determined similarity, diagnosing that the compressor cylinder comprises a condition. The signature vibration data may include resonance bands clustered within resonance band groups, each of the resonance band groups including a primary resonance band adjacent to a secondary resonance band.

That which is claimed: 
     
         1 . A diagnostic system for use with a compressor system having a compressor cylinder, the diagnostic system comprising:
 a sensor configured to measure a vibration signal of the compressor cylinder; and   a controller comprising a hardware processor and a machine-readable storage medium on which is stored instructions that cause the hardware processor to execute a diagnostic process, wherein the diagnostic process includes the steps of:
 storing a signature vibration data; 
 receiving a sample vibration data from the sensor, wherein the sample vibration data is representative of the vibration signal measured by the sensor over an operating period of the compressor cylinder; 
 comparing the sample vibration data to the signature vibration data to determine a similarity therebetween; and 
 based on the determined similarity, diagnosing that the compressor cylinder comprises a condition; 
   wherein the signature vibration data comprises resonance bands clustered within resonance band groups, each of the resonance band groups including a primary resonance band adjacent to a secondary resonance band.   
     
     
         2 . The diagnostic system according to  claim 1 , wherein the signature vibration data comprises multiple ones of the resonance band groups occurring at substantially regular intervals; and
 wherein each of the sample vibration data and the signature vibration data comprises vibration amplitude plotted against time.   
     
     
         3 . The diagnostic system according to  claim 2 , wherein the sensor comprises a knock sensor. 
     
     
         4 . The diagnostic system according to  claim 3 , wherein the sensor is attached to the compressor cylinder; and
 wherein the compressor cylinder is diagnosed as comprising the defect when the degree of similarity is determined to be beyond a predetermined threshold.   
     
     
         5 . The diagnostic system according to  claim 3 , wherein, between occurrences of the resonance band groups, the signature vibration data comprises an intervening signal, the intervening signal comprising a substantially regular amplitude that is significantly lower than an amplitude of each of the resonance bands within the resonance band groups; and
 wherein the resonance bands are each defined as a period in which the vibration amplitude increases rapidly to a peak and then falls away sharply.   
     
     
         6 . The diagnostic system according to  claim 5 , wherein each of the resonance band groups include a one of the primary resonance band positioned adjacent to and between ones of the secondary resonance bands such that:
 a leading secondary resonance band leads the primary resonance band; and   a trailing secondary resonance band trails the primary resonance band.   
     
     
         7 . The diagnostic system according to  claim 6 , wherein the compressor cylinder comprises a valve;
 wherein the condition comprises flutter within the valve.   
     
     
         8 . The diagnostic system according to  claim 6 , wherein the compressor cylinder comprises a plate valve, the plate valve including a sealing plate moveable between a seat and guard for controlling a flow through the plate valve. 
     
     
         9 . The diagnostic system according to  claim 8 , wherein the condition comprises an increased likelihood that the sealing plate is fluttering. 
     
     
         10 . The diagnostic system according to  claim 6 , wherein the diagnostic process further comprises the steps of:
 preparing an electronic communication regarding the diagnosis of the condition; and   transmitting the electronic communication as an alert to a user device of an operator of the compressor system.   
     
     
         11 . A computer-implemented method related to diagnosing a condition within a compressor system having a compressor cylinder, wherein a sensor is configured to measure a vibration signal of the compressor cylinder, the method comprising:
 receiving a sample vibration data from the sensor, wherein the sample vibration data is representative of the vibration signal measured by the sensor over an operating period of the compressor cylinder;   comparing the sample vibration data to a signature vibration data to determine a similarity therebetween; and   based on the determined similarity, diagnosing that the compressor cylinder comprises a condition;   wherein the signature vibration data comprises resonance bands clustered within resonance band groups, each of the resonance band groups including a primary resonance band adjacent to a secondary resonance band.   
     
     
         12 . The method according to  claim 11 , wherein the signature vibration data comprises multiple ones of the resonance band groups occurring at substantially regular intervals; and
 wherein each of the sample vibration data and the signature vibration data comprises vibration amplitude plotted against time.   
     
     
         13 . The method according to  claim 12 , wherein the sensor comprises a knock sensor. 
     
     
         14 . The method according to  claim 13 , wherein the sensor is attached to the compressor cylinder; and
 wherein the compressor cylinder is diagnosed as comprising the defect when the degree of similarity is determined to be beyond a predetermined threshold.   
     
     
         15 . The method according to  claim 13 , wherein, between occurrences of the resonance band groups, the signature vibration data comprises an intervening signal, the intervening signal comprising a substantially regular amplitude that is significantly lower than an amplitude of each of the resonance bands within the resonance band groups; and
 wherein the resonance bands are each defined as a period in which the vibration amplitude increases rapidly to a peak and then falls away sharply.   
     
     
         16 . The method according to  claim 15 , wherein each of the resonance band groups include a one of the primary resonance band positioned adjacent to and between ones of the secondary resonance bands such that:
 a leading secondary resonance band leads the primary resonance band; and   a trailing secondary resonance band trails the primary resonance band.   
     
     
         17 . The method according to  claim 16 , wherein the compressor cylinder comprises a valve;
 wherein the condition comprises flutter within the valve.   
     
     
         18 . The method according to  claim 16 , wherein the compressor cylinder comprises a plate valve, the plate valve including a sealing plate moveable between a seat and guard for controlling a flow through the plate valve. 
     
     
         19 . The method according to  claim 18 , wherein the condition comprises an increased likelihood that the sealing plate is fluttering. 
     
     
         20 . The method according to  claim 16 , further comprising the steps of:
 preparing an electronic communication regarding the diagnosis of the condition; and   transmitting the electronic communication as an alert to a user device of an operator of the compressor system.