Pressure relief valve monitoring device

Abstract

A pressure relief valve monitoring device is provided. The monitoring device includes a sensor input module located proximate to a pressure relief valve, a microcontroller located within the sensor input module, and a real time clock/calendar also located within the sensor input module. The monitoring device also includes a number of sensors, including (1) a position sensor mounted on the pressure relief valve for measuring the position of the valve's closure element relative to the inlet nozzle seat and for generating a lift signal representative of such position; (2) a pressure sensor mounted on the pressure relief valve for measuring the pressure of the pressure system and generating a pressure signal representative of such pressure; and (3) a leakage sensor mounted on the pressure relief valve and positioned in close proximity to the inlet nozzle seat and capable of detecting noise generated by leakage of fluid between the inlet nozzle seat and the closure element when the closure element is engaged with the inlet nozzle seat. The microcontroller is configured to receive and store signals from any or all of the three sensors and correlate the receipt thereof with an indication of time from the real time clock/calendar to determine certain characteristics of valve performance. A method for monitoring the operation of the pressure relief valve is also provided.

We claim:  
     
         1 . An apparatus for monitoring the operation of a pressure relief valve having a closure element engageable with a nozzle to block flow of fluid through the pressure relief valve, comprising: 
 a. a sensor input module including a microcontroller and a real time clock/calendar, said sensor input module located proximate to the pressure relief valve;    b. a leakage sensor for detecting leakage of fluid between the nozzle and the closure element and generating a leakage signal, said leakage sensor located proximate to the pressure relief valve and proximate to the nozzle; and    c. said microcontroller configured to receive said leakage signal and correlate the receipt thereof with an indication of time from said clock/calendar.    
     
     
         2 . The invention according to  claim 1  wherein said leakage sensor detects noise generated by leakage of fluid between the nozzle and the closure element.  
     
     
         3 . The invention according to  claim 1  wherein said leakage sensor is an acoustic sensor.  
     
     
         4 . The invention according to  claim 1  wherein said leakage sensor is a piezo electric crystal.  
     
     
         5 . An apparatus for monitoring the operation of a pressure relief valve having a closure element engageable with a nozzle to block flow of fluid through the pressure relief valve, comprising: 
 a leakage sensor for detecting noise generated by leakage of fluid between the nozzle and the closure element; said leakage sensor located proximate to the pressure relief valve and proximate to the nozzle.    
     
     
         6 . An apparatus for monitoring the operation of a pressure relief valve having a closure element engageable with a nozzle to block flow of fluid through the pressure relief valve, comprising: 
 means mounted on the pressure relief valve for detecting unstable operation of the pressure relief valve.    
     
     
         7 . A method for monitoring the operation of a pressure relief valve having a closure element in sealing engagement with a nozzle for blocking flow of fluid through the pressure relief valve, the pressure relief valve being located proximate to a sensor input module and to a leakage sensor, said method comprising the steps of: 
 a. detecting noise generated by leakage of fluid between the closure element and the nozzle using said leakage sensor;    b. generating a leakage signal in response to said noise; and    c. communicating said leakage signal to said sensor input module.    
     
     
         8 . The method as recited in  claim 7 , wherein said sensor input module has a microcontroller and a real time clock/calendar, said method further comprising the steps of: 
 generating an indication of time using said real time clock/calendar; and    correlating the receipt of said leakage signal with said indication of time using said microcontroller.    
     
     
         9 . The method as recited in  claim 7 , further comprising the step of: 
 generating an indication of time using a real time clock/calendar; and    storing said leakage signal as a function of time in said sensor input module.    
     
     
         10 . The method as recited in  claim 7 , further comprising the step of: 
 communicating said leakage signal to an enunciating device to activate an alarm.    
     
     
         11 . The method as recited in  claim 7 , further comprising the step of: 
 communicating said leakage signal to a process controller to activate an alarm.    
     
     
         12 . The method as recited in  claim 7 , further comprising the step of: 
 detecting noise having a characteristic frequency of the fluid leaking between the closure element and the nozzle.