Valve condition monitoring system for a positive displacement pump

A method of monitoring a condition of a positive displacement pump, the method comprising:

• supplying a fluid to a chamber at a fluid end of a pump;
• utilizing an intake pressure sensor to acquire intake pressure data of the fluid;
• pressurizing the fluid in the chamber, and discharging the fluid from the fluid end;
• utilizing a discharge pressure sensor to acquire discharge pressure data of the fluid being discharged from the fluid end;
• utilizing an encoder to acquire position information from moving internal components of the pump during the supplying of the fluid to the chamber, the pressurizing of the fluid, and the discharging of the fluid from the fluid end;
• correlating the intake pressure data and the discharge pressure data with the position information;
• determining magnitudes of deviations of the intake pressure data and the discharge pressure data from expected values of the intake pressure and the discharge pressure, respectively;
• and
• comparing the magnitudes of the deviations to one or more deviation thresholds.

A positive displacement pump assembly for operating at an oilfield and comprising:

• a positive displacement pump with a fluid end and a power end defining a chamber therebetween with at least one valve for governing fluid flow therein;
• an intake pressure sensor to monitor an intake pressure of a fluid flowing to the chamber;
• a discharge pressure sensor to monitor a discharge pressure of the fluid as the fluid flows from the chamber;
• an encoder coupled to the positive displacement pump to monitor reciprocation of the at least one valve;
• and
• an acquisition system to acquire data from each of the sensors and the encoder for establishing a substantially real-time condition of the positive displacement pump by causing a plurality of operations to be conducted, the operations comprising:
• utilizing the intake pressure sensor to acquire intake pressure data of the fluid as the fluid flows to the chamber;
• utilizing the discharge pressure sensor to acquire discharge pressure data of the fluid as the fluid flows from the chamber;
• utilizing the encoder to acquire position information of the at least one valve;
• correlating the intake pressure data and the discharge pressure data with the position information;
• determining magnitudes of deviations of the intake pressure data and the discharge pressure data from expected values of the intake pressure and the discharge pressure, respectively;
• and
• comparing the magnitudes of the deviations to one or more deviation thresholds.