Downhole pumping assembly and a downhole system

Patent metadata

Field	Value
Publication number	US-10180051-B2
Application number	US-201414899295-A
Country	US
Kind code	B2
Filing date	Jun 25, 2014
Priority date	Jun 26, 2013
Publication date	Jan 15, 2019
Grant date	Jan 15, 2019

Abstract

The present invention relates to a downhole pumping assembly for being introduced in a well inside a casing and submerged in well fluid, the downhole pumping assembly extending in a longitudinal direction and being adapted for connection with a wireline. The downhole pumping assembly comprises a pump section comprising a tubular pump housing providing a pump chamber, an inlet provided in the tubular pump housing, the inlet being in fluid communication with the pump chamber, a first valve which is a one-way valve arranged for opening and closing the inlet to allow fluid to flow into the chamber, a plunger slidably disposed in the pump chamber, a pump rod operably connected to the plunger and extending from the plunger through the tubular pump housing, an outlet provided in the tubular pump housing, the outlet being in fluid communication with the pump chamber, a second valve which is a one-way valve arranged for controlling a flow of fluid out of the chamber through the outlet. The downhole pumping assembly further comprises a linear actuator arranged in association with the tubular pump housing adapted to drive the pump rod, whereby, when the downhole pumping assembly is at least partially submerged into the well fluid, well fluid is drawn into the tubular pump housing through the inlet and expelled through the outlet in the tubular pump housing, and the pump section further comprises at least one sealing element for isolating a first part of the casing from a second part of the casing.

First claim

The invention claimed is:

1. A downhole pumping assembly for being introduced in a well inside a casing and submerged in well fluid, the downhole pumping assembly extending in a longitudinal direction and being adapted for connection with a wireline, and the downhole pumping assembly comprising a pump section comprising:
a tubular pump housing providing a pump chamber,
an inlet provided in the tubular pump housing, the inlet being in fluid communication with the pump chamber,
a first valve which is a one-way valve arranged for opening and closing the inlet to allow well fluid to flow into the chamber,
a plunger slidably disposed in the pump chamber and the first valve being separate from the plunger,
a pump rod operably connected to the plunger and extending from the plunger through the tubular pump housing,
an outlet provided in the tubular pump housing, the outlet being in fluid communication with the pump chamber, and
a second valve arranged at the outlet and which is a one-way valve arranged for controlling a flow of well fluid out of the chamber through the outlet,
wherein the downhole pumping assembly further comprises:
a linear actuator including a reciprocable stroker shaft, the linear actuator being arranged in association with the tubular pump housing, the stroker shaft being connected to the pump rod and adapted to reciprocatingly drive the pump rod, whereby, when the downhole pumping assembly is at least partially submerged into the well fluid, well fluid is drawn into the tubular pump housing through the inlet during movement of the stroker shaft in one direction and expelled through the outlet in the tubular pump housing during movement of the pump rod in a second direction opposite the first direction, and

wherein the pump section further comprises at least one sealing element for isolating a first part of the casing from a second part of the casing, and wherein the at least one sealing element is provided on each side of the outlet.

2. A downhole pumping assembly according to claim 1 , wherein the pump section comprises two sealing elements provided on each side of the outlet to create an isolated zone, and the inlet is positioned to receive well fluid from outside the isolated zone.

3. A downhole pumping assembly according to claim 2 , wherein the sealing elements are chevron seals.

4. A downhole pumping assembly according to claim 2 , wherein the sealing elements are compressible elements so that upon compression, an outer diameter of the sealing elements increases.

5. A downhole pumping assembly according to claim 2 , wherein the sealing elements are inflatable or expandable by injection of fluid.

6. A downhole pumping assembly according to claim 2 , wherein the sealing elements are cup seals.

7. A downhole pumping assembly according to claim 6 , wherein the two sealing elements are a first sealing element and a second sealing element, and wherein the first sealing element is a different type of sealing element than the second sealing element.

8. A downhole pumping assembly according to claim 1 , wherein the inlet is provided in an end face or a side wall of the pump chamber and the outlet is provided in the end face or the side wall of the pump chamber.

9. A downhole pumping assembly according to claim 1 , wherein the linear actuator comprises a plurality of piston elements slidably disposed in a plurality of piston housings and operably connected to the stroker shaft connected with the pump rod.

10. A downhole pumping assembly according to claim 1 , wherein the linear actuator comprises:
an electric linear motor,
wherein the stroker shaft is driven by the electric linear motor for connection with the pump rod to provide reciprocation of the plunger.

11. A downhole system comprising the downhole pumping assembly according to claim 1 , and the casing.

12. A downhole system according to claim 11 , wherein the casing comprises an annular barrier which comprises a tubular part mounted as part of the casing and an expandable sleeve surrounding the tubular part with an opening through which fluid enters to expand the sleeve, and wherein the pump section of the downhole pumping assembly is arranged opposite the opening for expanding the sleeve by pressurising fluid in an isolated section.

13. A downhole system according to claim 11 , wherein the casing is connected with a screen arranged outside the casing having an opening, and wherein the pump section of the downhole pumping assembly is arranged opposite the inlet of the screen for removing elements on an outside of the screen by pressurising fluid in the isolated section.

14. A method for removing elements on an outside of a screen using a downhole pumping assembly according to claim 1 , comprising the steps of:
inserting the downhole pumping assembly into the wellbore,
positioning the pump section of the downhole pumping assembly so that the sealing elements are positioned on each side of an opening to the screen, thereby sealing off the isolated section of the casing, and
operating the pump section to pump fluid into the isolated section of the casing, whereby fluid is forced in through the screen via the inlet and out into the wellbore.

15. A method for expanding an annular barrier using a downhole pumping assembly according to claim 1 , comprising:
inserting the downhole pumping assembly into the wellbore,
positioning the pump section of the downhole pumping assembly so that the sealing elements are positioned on each side of an opening of the annular barrier, thereby sealing off the isolated section of the casing, and
operating the pump section to pump fluid into the isolated section of the casing, whereby fluid is forced into the opening and expands an expandable sleeve of the annular barrier.

16. A downhole system according to claim 11 , wherein the linear actuator includes a hydraulic pump operable by hydraulic fluid, the pump being configured to supply hydraulic fluid to a tubular stroker cylinder associated with the stroker shaft to reciprocate same.

17. A downhole system according to claim 11 , wherein the pump housing includes a first compartment and a second compartment separated by the plunger, wherein the first compartment of the pump housing includes both the first and second one-way valves.

18. A downhole system according to claim 17 , wherein the second compartment includes a passage, the inlet to the first compartment and the passage to the second compartment being positioned to receive well fluid from an exterior section of the pump housing, wherein the passage to the second compartment allows well fluid to enter into and flow out of the second compartment during reciprocable movement of the pump rod.

Assignees

• Welltec Oilfield Solutions Ag

Inventors

• Vasques Ricardo Reves

Classifications

• F04B47/026

  Pull rods, full rod component parts · CPC title

• F04B47/02

  the driving mechanisms being situated at ground level (F04B47/12 takes precedence) · CPC title

• E21B33/126

  with fluid-pressure-operated elastic cup or skirt (E21B33/122, E21B33/124 take precedence) · CPC title

• E21B43/103

  of expandable casings, screens, liners, or the like · CPC title

• E21B43/127

  Adaptations of walking-beam pump systems · CPC title