Threaded connection partially in a self-locking engagement

Patent metadata

Field	Value
Publication number	US-11840895-B2
Application number	US-201816754031-A
Country	US
Kind code	B2
Filing date	Oct 2, 2018
Priority date	Oct 20, 2017
Publication date	Dec 12, 2023
Grant date	Dec 12, 2023

Abstract

A threaded connection partially in a self-locking arrangement includes a first and a second tubular component provided respectively with male and female threaded zone at their respective ends. Only a portion of a first portion with varying thread width of the male threaded zone cooperates by self-locking tightening with only a portion of the second portion with varying thread width of the female threaded zone when made up one into the other. The connection is able to withstand high torques required for special applications such as drilling with casing or intermediate casing.

First claim

The invention claimed is:

1. A threaded connection comprising:
a first and a second tubular component, the first tubular component being provided with a pipe body and a male member at a distal end of the pipe body, the second tubular component being provided with another pipe body and a female member at a distal end of that pipe body, such that a male member comprises, on an external peripheral surface, at least one male threaded zone and finishes in a male terminal surface, and a female member comprises, on an internal peripheral surface, at least one female threaded zone and finishes in a female terminal surface,
the male threaded zone comprising a male thread having a first portion in which the width of a thread crest increases continuously over an entirety of the first portion in a direction oriented from the male terminal surface towards the pipe body of the first tubular component, a tooth closest to the male terminal surface presenting a minimum crest width value of the male thread, and
the female threaded zone comprising a female thread having a second portion in which the width of a thread crest increases continuously over an entirety of the second portion along a direction oriented from the female terminal surface towards the pipe body of the second tubular component, a tooth closest to the female terminal surface presenting a minimum crest width value of the female thread,
wherein each tooth of the first portion is between two adjacent teeth of the second portion when the connection is made up, and wherein only part of the first portion cooperate with only a part of the second portion in accordance with a self-locking make-up arrangement in order to provide a locking region in the threaded connection.

2. The threaded connection according to claim 1 , wherein the locking region comprises a number of threads in self-locking arrangement, wherein first and second portions comprise a number of threads strictly greater than the number of threads of the locking region.

3. The threaded connection according to claim 1 , wherein the male threaded zone has a male distal portion defined by a different wedge ratio than in the locking region, the distal portion including the tooth that is closest to the male terminal surface, the male distal portion being adjacent to the first portion.

4. The threaded connection according to claim 3 , wherein the female threaded zone has a female distal portion defined by a different wedge ratio than in the locking region, the female distal portion including the tooth which is closest to the female terminal surface, the female distal portion being adjacent to the second portion.

5. The threaded connection according to claim 4 , wherein the tooth of the female distal portion which is closest to the female terminal surface has the same crest width as the tooth of the male distal portion which is closest to the male terminal surface.

6. The threaded connection according to claim 1 , wherein a lead of a male stab flanks is constant in the first portion and gets a distinct value in a distal portion of the male threaded zone, the distinct value being lower or equal to the value of a lead of a male load flanks which remains constant in the first and distal portions, the male distal portion being adjacent to the first portion.

7. The threaded connection according to claim 1 , wherein a lead of the male load flanks is constant in the first portion and gets a distinct value in a distal portion of a male threaded zone a value greater or equal to the value of a lead of a male stab flanks which remains constant in the first and distal portions, the male distal portion being adjacent to the first portion.

8. The threaded connection according to claim 1 , wherein the male threaded zone has a male proximal portion defined by a different wedge ratio than in the locking region, the proximal portion including the tooth that is farthest to the male terminal surface, the male proximal portion being adjacent to the first portion.

9. The threaded connection according to claim 1 , wherein the female threaded zone has a female proximal portion defined by a different wedge ratio than in the locking region, the proximal portion including the tooth that is farthest to the female terminal surface, the female proximal portion being adjacent to the second portion.

10. The threaded connection according to claim 1 , wherein a lead of a male stab flanks is constant in the first portion and gets in a proximal portion of the male threaded zone a value lower or equal to the value of a lead of a male load flanks which remains constant in the first and proximal portions, the male proximal portion being adjacent to the first portion.

11. The threaded connection according to claim 1 , wherein a lead of a male load flanks is constant in the first portion and gets in a proximal portion of the male threaded zone a value greater or equal to the value of a lead of a male stab flanks which remains constant in the first and proximal portions, the male proximal portion being adjacent to the first portion.

12. The threaded connection according to claim 1 , wherein a wedge ratio changes at two locations on both the male threaded zone and the female threaded zone.

13. The threaded connection according to claim 1 , wherein a lead of a male stab flanks changes at two locations on the male threaded zone and a female stab flanks changes at two locations on a female threaded zone, and wherein a lead of male load flanks and a lead of a female load flanks remain constant along the whole male threaded zone, and respectively female threaded zone.

14. The threaded connection according to claim 1 , wherein the male threaded zone comprise dovetail thread, and the minimum value (CWTpmin) of the width of the tooth which is closest to the male terminal surface fulfill at least one of the below equations

⁢

0.8202
*
TH

≤
CWTpmin

(
a
)

CWTpmin
≤

BTG
-

(

PLH
*

tan
⁡

(
α
)

)

-

(

[

PLH
+

(

LFP_p
⁢

Assignees

• Vallourec Oil & Gas France
• Nippon Steel Corp

Inventors

• Langford Steve
• Ott Wesley

Classifications

• E21B17/043 Primary

  with locking means · CPC title

• F16L15/004

  with axial sealings having at least one plastically deformable sealing surface (with sealing rings F16L15/003) · CPC title

• E21B17/046

  with ribs, pins, or jaws, and complementary grooves or the like, e.g. bayonet catches · CPC title

• F16L15/06

  characterised by the shape of the screw-thread · CPC title

• F16L2201/40

  for special environments · CPC title