Well fluid sampling apparatus with isolation valve and check valve

• US 6,182,753 B1
• Filed: 12/16/1999
• Issued: 02/06/2001
• Est. Priority Date: 09/23/1997
• Status: Expired due to Fees

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Schultz, Roger L.
• Primary Examiner(s): NOLAND, THOMAS
• Application Number:
  US09/464,760
• Time in Patent Office: 418 Days
• Field of Search: 166/162, 166/264, 738/64, 738/645.1, 738/646.3, 738/630--86, 738/646.2, 731/522.3, 731/522.7, 731/522.8
• US Class Current: 166/162
• CPC Class Codes: E21B 49/0813 Sampling valve actuated by annulus pressure changes
• CPC Class Codes: E21B 49/0815 Sampling valve actuated by tubing pressure changes

Abstract

A non-flashing fluid sampler for use in obtaining a well fluid sample. The sampler comprises a body defining a first chamber, a second chamber, a third chamber and a sampling port therein. The sampling port is in communication with the first chamber and with an outside zone outside the body. The second and third chambers are initially isolated from one another by a control valve. Upon activating the control valve, fluid may flow from the second chamber to the third chamber through a flow restriction. An extendable floating piston is disposed between the first and second chambers, and the floating piston defines a variable volume therein. An initial amount of well fluid flows into the variable volume, thus trapping dirty fluid, and subsequently, a well fluid sample is flowed into the first chamber. An isolation valve is provided for allowing hydrostatic pressure into the sampler after the fluid sample has been taken. Check valves prevent outward fluid flow from the sampler and thereby trap the hydrostatic pressure therein. Methods of use of the sampling apparatus are also disclosed.

Claims

1. A fluid sampling apparatus for use adjacent to a zone of interest in a well, the apparatus comprising:

a body having a plurality of chambers and a sampling port defined therein, the sampling port being in communication with one of the chambers and an outside zone of the body such that a fluid sample may be flowed into the one of the chambers;

an isolation valve, disposed in the body, for allowing hydrostatic pressure from the well into the body substantially after flowing the fluid sample and thereby communicating the hydrostatic pressure to the chambers; and

a check valve for preventing fluid flow outwardly from the body and thereby trapping the hydrostatic pressure in the body.

2. The apparatus of claim 1 wherein:

the one chamber is a first chamber; and

the plurality of chambers further comprises a second chamber and a third chamber; and

further comprising;

a floating piston in communication with the third chamber and movable in response to fluid flow from the second chamber to the third chamber.

3. The apparatus of claim 2 further comprising a plunger for opening the isolation valve in response to predetermined movement of the floating piston.

4. The apparatus of claim 3 wherein:

the body further defines an air chamber therein; and

the plunger is disposed in the air chamber.

5. The apparatus of claim 3 wherein the plunger defines a differential area thereon such that, when the hydrostatic pressure is applied thereto, the plunger and floating piston are forced downwardly, thereby raising a pressure of fluid in the body to a level above the hydrostatic pressure.

6. The apparatus of claim 5 wherein fluid pressure in each of the first, second and third chambers is raised to the level above the hydrostatic pressure.

7. The apparatus of claim 1 wherein the check valve comprises a ball check valve in communication with the isolation valve.

8. The apparatus of claim 1 wherein the check valve comprises a slidable check valve disposed between the sampling port and the one chamber.

9. The apparatus of claim 1 further comprising a floating piston disposed between two of the chambers.

10. The apparatus of claim 1 wherein:

the one chamber is a first chamber; and

the plurality of chambers further comprises a second chamber and a third chamber; and

further comprising;

a control valve, disposed in the body between the second and third chambers, for initially isolating the second chamber from the third chamber and for allowing fluid flow from the second chamber to the third chamber when activated.

11. The apparatus of claim 10 further comprising an activator for activating the control valve.

12. The apparatus of claim 11 wherein:

the body further defines a control port therein, the control port being communicated with a second outside zone outside the body; and

the activator is disposed in the control port and adapted for opening the control port in response to outside pressure from the second outside zone.

13. The apparatus of claim 12 wherein the activator is adapted for activating the control valve when a pressure differential between the second outside zone and the control valve reaches a predetermined level.

14. The apparatus of claim 13 wherein the activator comprises a rupture disc disposed across the control port.

15. The apparatus of claim 1 wherein:

the one chamber is a first chamber; and

the plurality of chambers further comprises a second chamber and a third chamber; and

further composing;

a flow restrictor, disposed in the body between the second and third chambers, for impeding fluid flow from the second chamber to the third chamber.

16. A fluid sampling apparatus for use adjacent to a zone of interest in a well, the apparatus comprising:

a body having a first chamber, a second chamber and a third chamber and a sampling port defined therein, the sampling port being in communication with the first chamber and an outside zone outside the body;

a floating piston in communication with the third chamber and movable in response to fluid flow from the second chamber to the third chamber;

an isolation valve, disposed in the body, for allowing hydrostatic pressure from the well into the body and thereby communicating the hydrostatic pressure to the chambers;

a check valve for preventing fluid flow outwardly from the body and thereby trapping the hydrostatic pressure in the body; and

a plunger for opening the isolation valve in response to predetermined movement of the floating piston wherein;

the plunger defines a differential area thereon such that, when the hydrostatic pressure is applied thereto, the plunger and floating piston are forced downwardly, thereby raising the pressure of fluid in the body to a level above the hydrostatic pressure; and

the differential area is defined as the difference in a cross-sectional area of an upper end of the plunger and a cross-sectional area of a lower end of the plunger, the lower end of the plunger being smaller than the upper end of the plunger.

17. The apparatus of claim 16 further comprising:

a seal disposed between the body and the upper end of the plunger; and

another seal disposed between the body and the lower end of the plunger.

18. A fluid sampling apparatus for use adjacent to a zone of interest in a well, the apparatus comprising:

a body having a plurality of chambers and a sampling port defined therein, the sampling port being in communication with one of the chambers and an outside zone outside the body;

an isolation valve, disposed in the body, for allowing hydrostatic pressure from the well into the body and thereby communicating the hydrostatic pressure to the chambers;

a check valve for preventing fluid flow outwardly from the body and thereby trapping the hydrostatic pressure in the body;

and a floating piston disposed between two of the chambers, the floating piston comprising;

a first piston portion; and

a second piston portion relatively movable with respect to the first piston portion, the first and second piston portions defining a variable volume therebetween.

19. The apparatus of claim 18 further comprising a lock for locking the first and second piston portions to one another after predetermined relative movement between the first and second piston portions.

20. The apparatus of claim 18 wherein the variable volume defined in the floating piston is in communication with the sampling port.