System and method for determining onset of failure modes in a positive displacement pump

• US 8,366,402 B2
• Filed: 12/20/2005
• Issued: 02/05/2013
• Est. Priority Date: 12/20/2005
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: St. Michel, Nathan, Wago, Toshimichi, Hubenschmidt, Joe, Pessin, Jean-Louis
• Primary Examiner(s): Freay, Charles
• Assistant Examiner(s): COMLEY, ALEXANDER BRYANT
• Application Number:
  US11/312,124
• Publication Number:
  US 20070140869A1
• Time in Patent Office: 2,604 Days
• Field of Search: 417/53, 417/63, 417/297, 417/454, 702/34
• US Class Current: 417/63
• CPC Class Codes: E21B 47/009 Monitoring of walking-beam pump systems
• CPC Class Codes: F04B 19/22 of reciprocating-piston type
• CPC Class Codes: F04B 2201/0201 Position of the piston
• CPC Class Codes: F04B 2201/0603 Valve wear
• CPC Class Codes: F04B 47/00 Pumps or pumping installations specially adapted for raising fluids from great depths, e.g. well pumps by using positive or negative pressurised fluid medium acting directly on the liquid to be pumped F04F1/00
• CPC Class Codes: F04B 49/22 by means of valves F04B49/03 takes precedence
• CPC Class Codes: F04B 51/00 Testing machines, pumps, or pumping installations
• CPC Class Codes: F04B 9/00 Piston machines or pumps characterised by the driving or driven means to or from their working members

Abstract

A reciprocating pump system is utilized. The system facilitates the prediction of failure modes due to degradation of pump components. A sensor system is used to monitor parameters indicative of abnormal events or wear occurring in specific components, such as pump valves. The indications of wear can be used to predict valve failure or other component failure within the reciprocating pump.

Claims

1. A method, comprising:

monitoring a pump chamber pressure in a pump chamber of a positive displacement pump;

detecting a plunger position within the pump chamber of the positive displacement pump;

determining at least one of a suction lag corresponding to a suction valve and a discharge lag corresponding to a discharge valve;

measuring a discharge pressure of the positive displacement pump;

determining the at least one of the suction lag in response to at least one of D1 and A1, wherein D1 reflects a time difference between an event marking the detection of a bottom-dead-center plunger position and a subsequent event marking the pump chamber pressure being equal to at least one-half of the discharge pressure, and wherein A1 reflects a time difference between the event marking the detection of a bottom-dead-center plunger position and another event marking the detection of closing the suction valve;

outputting at least one of the suction lag and the discharge lag to a control system and accumulating data relating to said pump chamber pressure, said plunger position, and said at least one of the suction lag and the discharge lag over consecutive operations of the positive displacement pump; and

,

running a regression program on said accumulated data to provide an estimated time to failure for one of the suction valve and the discharge valve.

2. The method as recited in claim 1, wherein monitoring comprises monitoring pump chamber pressures within a plurality of pump chambers within the positive displacement pump.

3. The method as recited in claim 1, wherein determining comprises determining the closing time of the suction valve and the discharge valve with at least one accelerometer positioned in the positive displacement pump.

4. The method as recited in claim 1, further comprising processing the data to determine any parameter timing changes indicative of future failure of the at least one of the suction valve and the discharge valve.

5. The method as recited in claim 1, further comprising processing the data to determine any changes in rising and falling slopes of a pump chamber pressure waveform indicative of future failure of the at least one of the suction valve and the discharge valve.

6. The method as recited in claim 1, further comprising processing the data to perform frequency spectrum analyses on an accelerometer signal to determine changes in the frequency spectrum over time.

7. The method as recited in claim 1, further comprising determining the at least one of the suction lag and the discharge lag in response to the pump chamber pressure being equal to the discharge pressure.

8. The method as recited in claim 1, further comprising determining the at least one of the suction lag and the discharge lag in response to the pump chamber pressure being equal to at least one-half of the discharge pressure.

9. The method as recited in claim 1, further comprising determining the suction lag in response to determining a point of deviation of the pump chamber pressure from a low-pressure suction scheme.

10. The method as recited in claim 1, further comprising determining the discharge lag in response to determining a point of deviation of the pump chamber pressure to a low-pressure suction scheme.

11. The method as recited in claim 2, further comprising tracking the at least one of the suction lag and the discharge lag over several consecutive pumping jobs.

12. The method as recited in claim 11, wherein the pumping jobs comprise frac jobs.

13. The method as recited in claim 2, further comprising determining a plurality of suction lag values corresponding to each of the pump chambers.

14. The method as recited in claim 2, further comprising determining a plurality of discharge lag values corresponding to each of the pump chambers.

15. The method as recited in claim 1, wherein said method is for pumping well stimulation fluid into a reservoir for a well stimulation.

16. The method as recited in claim 1, further comprising determining the at least one of the discharge lag in response to at least one of D2 and A2, wherein D2 reflects a time difference between an event marking the detection of a top-dead-center plunger position and a subsequent event marking the pump chamber pressure being equal to at least one-half of the discharge pressure;

and wherein A2 reflects a time difference between the event marking the detection of a top-dead-center plunger position and another event marking the detection of closing the discharge valve.

17. A method, comprising:

monitoring a pump chamber pressure in a pump chamber of a positive displacement pump;

detecting a plunger position within the pump chamber of the positive displacement pump;

determining at least one of a suction lag corresponding to a suction valve and a discharge lag corresponding to a discharge valve;

measuring a discharge pressure of the positive displacement pump;

determining the at least one of the discharge lag in response to at least one of D2 and A2, wherein D2 reflects a time difference between an event marking the detection of a top-dead-center plunger position and a subsequent event marking the pump chamber pressure being equal to at least one-half of the discharge pressure; and

wherein A2 reflects a time difference between the event marking the detection of a top-dead-center plunger position and another event marking the detection of closing the discharge valve;

outputting at least one of the suction lag and the discharge lag to a control system and accumulating data relating to said pump chamber pressure, said plunger position, and said at least one of the suction lag and the discharge lag over consecutive operations of the positive displacement pump; and

,

running a regression program on said accumulated data to provide an estimated time to failure for one of the suction valve and the discharge valve.

18. The method as recited in claim 17, further comprising determining the at least one of the suction lag in response to at least one of D1 and A1, wherein D1 reflects a time difference between an event marking the detection of a bottom-dead-center plunger position and a subsequent event marking the pump chamber pressure being equal to at least one-half of the discharge pressure;

and wherein A1 reflects a time difference between the event marking the detection of a bottom-dead-center plunger position and another event marking the detection of closing the suction valve.