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Patent Searching and Data


Title:
MULTI-ZONE HYDRAULIC STIMULATION SYSTEM
Document Type and Number:
WIPO Patent Application WO/2019/108776
Kind Code:
A4
Abstract:
A system includes a string disposed in a wellbore, a first valve coupled to the string, the first valve including a sleeve having an engagement profile with a first coded sequence, a second valve coupled to the string, the second valve including a sleeve having an engagement profile with a second coded sequence that differs from the first coded sequence of the first valve, and a first dart flow transportable through the string, the first dart including a collet finger having a first coded sequence configured to restrict the collet finger from matingly engaging the engagement profile of the first valve while permitting the collet finger to engage the engagement profile of the second valve, wherein the first dart actuates the sleeve of the second valve between first and second positions in response to the collet finger of the first dart matingly engaging the engagement profile of the second valve.

Inventors:
CALAHAN SEAN (US)
ABRAHAM AJU (US)
NOWOWIEJSKI DAVID (US)
SHEWCHUK CHRIS (US)
Application Number:
PCT/US2018/063034
Publication Date:
July 25, 2019
Filing Date:
November 29, 2018
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
NAT OILWELL VARCO LP (US)
International Classes:
E21B34/14; E21B34/00; E21B34/06; E21B34/10
Attorney, Agent or Firm:
HOOPER, James A. et al. (US)
Download PDF:
Claims:
AMENDED CLAIMS

received by the International Bureau on 26 June 2019 (26.06.2019)

In the Claims

What is claimed is:

1. A system for stimulating an earthen formation, comprising:

a tubular string disposed in a wellbore extending through the formation;

a first valve coupled to the tubular string, the first valve comprising a sliding sleeve having an engagement profile with a first coded sequence;

a second valve coupled to the tubular string, the second valve comprising a sliding sleeve having an engagement profile with a second coded sequence that differs from the first coded sequence of the first valve; and

a first dart flow transportable through the tubular string, the first dart comprising a collet finger having a first coded sequence configured to restrict the collet finger from matingly engaging the engagement profile of the first valve while permitting the collet finger to matingly engage the engagement profile of the second valve;

wherein the first dart is configured to actuate the sliding sleeve of the second valve from a first position to a second position in response to the collet finger of the first dart matingly engaging the engagement profile of the second valve.

2. The system of claim 1 , further comprising:

a second dart flow transportable through the tubular string, the second dart comprising a collet finger having a second coded sequence that differs from the first coded sequence of the first dart and configured to permit the collet finger to matingly engage the engagement profile of the first valve;

wherein the second dart is configured to actuate the sliding sleeve of the first valve from a first position to a second position in response to the collet finger of the second dart matingly engaging the engagement profile of the first valve.

3. The system of claim 1 , wherein:

the engagement profile of the sliding sleeve of the second valve comprises a locking groove and the collet finger of the first dart comprises a locking shoulder;

the locking groove and the locking shoulder being configured to axially lock the first dart to the sliding sleeve of the second valve after the sliding sleeve of the second valve has actuated to the second position.

4. The system of claim 1 , wherein:

the engagement profile of the sliding sleeve of both the first valve and the second valve comprises a plurality of axially spaced coding grooves;

the first valve comprises a first blocking member disposed in one of the coding grooves of the engagement profile of the sliding sleeve of the first valve; and

the second valve comprises a second blocking member disposed in one of the coding grooves of the engagement profile of the sliding sleeve of the second valve.

5. The system of claim 4, wherein:

a plurality of axially spaced keyways are disposed on an outer surface of the collet finger of the first dart;

at least one key is received in one of the keyways of the collet finger;

the at least one key of the first dart axially overlaps the blocking member of the first valve when the keyways of the collet finger of the first dart are axially aligned with the coding grooves of the sliding sleeve of the first valve, preventing mating engagement between the collet finger of the first dart and the engagement profile of the first valve; and the at least one key of the first dart is axially spaced from the blocking member of the second valve when the keyways of the collet finger of the first dart are axially aligned with the coding grooves of the sliding sleeve of the second valve, permitting mating engagement between the collet finger of the first dart and the engagement profile of the second valve.

6. The system of claim 4, wherein the first dart comprises:

a pair of elongate retaining members extending along a pair of sides of the collet finger; and

a plurality of fasteners releasably coupling the retaining members to the collet finger;

wherein the retaining members releasably couple the at least one key to the collet finger.

7. The system of claim 4, wherein the sliding sleeve of the second valve comprises: a first protective groove located at a first end of the engagement profile;

a second protective groove located at a second end of the engagement profile opposite the first end; and

29 a locking groove located between the first protective groove and the second protective groove.

8. The system of claim 7, wherein the first dart comprises:

a pair of axially spaced protective shoulders extending radially outward from the collet finger, wherein the protective shoulders are configured to be received in the first and second protective grooves of the sliding sleeve of the second valve; and

a locking shoulder extending radially outward from the collet finger, wherein the locking shoulder is located between the pair of protective shoulders, wherein the locking shoulder is configured to be received in the locking groove of the sliding sleeve of the second valve.

9. The system of claim 1 , wherein the first dart comprises:

a nose coupled to a first end of a collet;

an entry guide coupled to a second end of the collet opposite the first end, the entry guide configured to guide the dart through the wellbore; and

an annular seal disposed on an outer surface of the collet and configured to seal against a sealing surface disposed in the wellbore;

wherein the nose and entry guide are formed from dissolvable materials configured to dissolve in response to a predetermined environmental condition within the wellbore.

10. A sliding sleeve valve for use in a wellbore, comprising:

an outer housing;

a sliding sleeve slidably disposed in the outer housing, the sliding sleeve comprising an engagement profile formed on an inner surface thereof, wherein the engagement profile comprises a plurality of axially spaced coding grooves; and

at least one blocking member configured to be received in one of the coding grooves of the sliding sleeve;

wherein the engagement profile is configured to form a coded sequence when the at least one blocking member is received in one of the coding grooves of the sliding sleeve; and

30 wherein the sliding sleeve is configured to actuate from a first position to a second position in response to an actuation tool matingly engaging the engagement profile of the sliding sleeve.

11. The sliding sleeve valve of claim 10, wherein the at least one blocking member comprises at least one blocking ring molded to one of the coding grooves of the sliding sleeve.

12. The sliding sleeve valve of claim 10, wherein the engagement profile of the sliding sleeve further comprises:

a first protective groove located at a first end of the engagement profile;

a second protective groove located at a second end of the engagement profile opposite the first end; and

a locking groove located between the first protective groove and the second protective groove.

13. The sliding sleeve valve of claim 10, further comprising:

a protective sleeve disposed at least partially in the sliding sleeve;

wherein the protective sleeve has a first position relative to the sliding sleeve covering the coding grooves of the engagement profile and a second position relative to the sliding sleeve axially spaced from the coding grooves.

14. The sliding sleeve valve of claim 10, wherein:

the outer housing comprises a radial port;

the sliding sleeve comprises a pair of annular seals disposed on an outer surface thereof; and

the annular seals of the sliding sleeve seal a passage of the outer housing from an environment surrounding the sliding sleeve valve when the sliding sleeve is in the first position and permit fluid communication between the passage of the outer housing and the environment surrounding the sliding sleeve when the sliding sleeve is in the second position.

15. A dart flow transportable through a wellbore, comprising:

a collet;

31 a collet finger coupled to the collet;

a plurality of axially spaced keyways disposed on an outer surface of the collet finger; and

at least one key configured to be received in one of the keyways of the collet finger;

wherein the collet is configured such that when the at least one key is received in one of the keyways of the collet finger, the collet finger forms a coded sequence.

16. The dart of claim 15, wherein:

the collet comprises a plurality of circumferentially spaced collet fingers;

each collet finger comprising a plurality of axially spaced keyways disposed on an outer surface of the collet finger;

one keyway of each collet finger receives one of the at least one keys.

17. The dart of claim 15, further comprising:

a pair of elongate retaining members extending along a pair of sides of the collet finger; and

a plurality of fasteners releasably coupling the retaining members to the collet finger;

wherein the retaining members releasably couple the at least one key to the collet finger.

18. The dart of claim 15, wherein:

the plurality of keyways of the collet finger comprise arcuate keyways; and the at least one key comprises an arcuate key.

19. The dart of claim 15, further comprising:

a nose coupled to a first end of the collet;

an entry guide coupled to a second end of the collet opposite the first end, the entry guide configured to guide the dart through the wellbore; and

an annular seal disposed on an outer surface of the collet and configured to seal against a sealing surface disposed in the wellbore;

32 wherein the nose and entry guide are formed from dissolvable materials configured to dissolve in response to a predetermined environmental condition within the wellbore.

20. The dart of claim 15, further comprising:

a pair of axially spaced protective shoulders extending radially outward from the collet finger; and

a locking shoulder extending radially outward from the collet finger, wherein the locking shoulder is located between the pair of protective shoulders.

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