Assembly and method of alternative pumping using hollow rods without tubing

• US 20060278398A1
• Filed: 06/06/2006
• Published: 12/14/2006
• Est. Priority Date: 06/07/2005
• Status: Active Grant

• Current Assignee: Ypf Sociedad Anonima
• Original Assignee: Ypf Sociedad Anonima
• Inventors: Ruggeri, Jorge, Bianchetti, Omar, Scaramuzza, Jose L.
• Granted Patent: US 7,647,962 B2
• Time in Patent Office: Days
• US Class Current: 166/369
• CPC Class Codes: E21B 17/046 with ribs, pins, or jaws, and complementary grooves or the like, e.g. bayonet catches
• CPC Class Codes: E21B 17/1014 Flexible or expansible centering means, e.g. with pistons pressing against the wall of the well E21B17/1042 takes precedence
• CPC Class Codes: E21B 43/127 Adaptations of walking-beam pump systems
• CPC Class Codes: F04B 47/02 the driving mechanisms being situated at ground level F04B47/12 takes precedence
• CPC Class Codes: F04B 47/026 Pull rods, full rod component parts
• CPC Class Codes: F04B 47/028 details of the walking beam

Abstract

Assembly and method for extracting fluids, preferably crude oil, from a drilled well within a geological formation by means of reciprocating pumping with hollow sucker rods. The assembly includes: a) a stationary bottom set attached to the casing at the desired depth and providing the rod pump anchoring system; b) a reciprocating axial movement rod pump having an anchoring system and a centralizer; c) a centralized hollow rod string extending within the well, which is connected to the mobile member of the pump; d) a hollow polished rod connected to the hollow rod string and linked to a system that imparts the reciprocating axial movement to the pump; e) a production bridge connecting the polished rod to the driving tubing through rotating joints, and f) a rigid head that provides a venting exit of the annular space formed between the string and the casing.

Claims

1. An assembly for extracting a fluid from a drilled well within a geological formation, which walls are secured by means of a casing that is drilled at pre-selected depth levels, the device comprising:

a) a stationary bottom set configured to anchor to the casing for a deep well pump;

b) a deep well pump with reciprocating axial movement comprising a stationary member and a mobile member, an anchorage system in the bottom part, and a centralizer in the top part, the latter two being integral to the stationary member;

c) a series of interconnected hollow rods forming a string that extends within the well and is connected by its bottom end to the mobile member of the rod pump, such that the inside of the mobile member of the pump is in fluid communication with the interior of the hollow rod string;

d) a hollow polished rod that is connected by its bottom end to the free top end of the hollow rod string within the well, said polished rod being linked to a system that imparts a reciprocating axial movement;

e) a production bridge that links the top end of the hollow polished rod to the driving pipeline, which allows the recovery of the fluid pumped from the interior of the hollow rods and from said hollow polished rod; and

f) a rigid head providing a packing in the annular space between the polished rod and the casing, equipped with a hollow polished rod lubricating device.

2. The assembly according to claim 1, wherein the stationary bottom set includes an anchor comprising an attachment system to the casing and a centralizer hub equipped with friction blocks, mechanical and in cups seating shoes, and a connecting set.

3. The assembly according to claim 2, wherein the stationary bottom set further comprises a housing tube for the pump and a centralizer thereof.

4. The assembly according to claim 2, wherein the attachment system of the anchor are of the type that allows for free fluid flow.

5. The assembly according to claim 2, wherein the connecting set comprises a connecting tube equipped with pins transversal to the tube axis and a connecting hood provided with a “

J”

-shaped slot, so that the pins fit in the “

J”

slot of the hood to assemble the tube-hood connector set.

6. The assembly according to claim 1, wherein the reciprocating axial movement rod pump comprises a stationary member or barrel provided with a stationary valve and a mobile member comprising a traveling valve and the piston-pull tube set.

7. The assembly according to claim 6, wherein the pull tube is connected to the hollow rod string by means of a flow linking tube that enables the fluid flow from within the pump mobile member to the interior of the hollow rod string.

8. The assembly according to claim 7, wherein the flow linking tube has a drain plug, susceptible of being sectioned for its opening, during the pump extracting maneuvers.

9. The assembly according to claim 7, wherein the flow linking tube is connected with the pump pull tube by means of a flexible connection.

10. The assembly according to claim 6, wherein the stationary member has a mechanical anchorage and an anchorage in cups for anchoring in the respective mechanical and in cups seating shoes, of the stationary bottom set.

11. The assembly according to claim 1, wherein the centralizers comprise a centralizer hub equipped with friction blocks, and actuated by springs.

12. The assembly according to claim 1, wherein the hollow rod string comprises female threaded end tubes, interconnected by means of male threaded end tubular sleeves.

13. The assembly according to claim 12, wherein the hollow rod string has at least one centralizer surrounding it.

14. The assembly according to claim 1, wherein the connection between the hollow polished rod and the production bridge is a rotating joint.

15. The assembly according to claim 1, wherein the production bridge comprises rigid tubes connected to one another and to the driving pipeline by rotating type joints.

16. The assembly according to claim 1, wherein the rigid head is threaded to the casing tube top end, said head being further equipped with a venting valve from the annular space formed between the hollow polished rod and the casing.

17. The assembly according to claim 1, wherein the rigid head comprises a seal box with a lubricating device that allows for packing the annular space at the polished rod exit outside the well and for lubricating the friction surface between polished rod and seals.

18. The assembly according to claim 1, wherein the fluid is a hydrocarbon.

19. A method for extracting a fluid from a drilled well within a geological formation, which walls are secured by means of a casing, perforated to selected depth levels, by means of the assembly according to claim 1, the method comprising the steps of:

a) assembling and lowering a stationary bottom set into the well, attaching it to the casing walls at the desired depth and recovering the tool used for the descent;

b) building an anchoring system in the bottom end and a centralizer in the top end of an axial reciprocating movement rod pump stationary member, connecting the mobile end of the pump to a centralized hollow rod, wherein such connection is of the type that enables the pumped fluid to pass from within the pump to the interior of the hollow rod;

c) interconnecting a centralized hollow rod string by means of sleeves, to form a string that extends into the well, until anchoring the pump in the bottom set;

d) connecting a hollow polished rod to the free end of the hollow rod string by means of a sleeve and suspending said polished rod of the system that imparts the reciprocating axial movement;

e) installing a surface head that provides a venting orifice of the annular space formed between the casing and the polished rod and a gasket between the casing and the polished rod extension outside the well;

f) assembling the upper end of the polished rod to a production bridge equipped with rotating joints that allow its connection to the surface driving tubing;

g) actuating such hollow polished rod according to a reciprocating axial movement;

h) recovering the pumped fluid that flows up from the interior of the hollow rod string and the hollow polished rod and deliver it through the production bridge to the surface driving pipeline.

20. The method according to claim 19, wherein the fluid is a hydrocarbon.