IP Library Granted Patent US 7,497,481
Granted Patent B2
US 7,497,481 · App. 11/129,214 · Granted Mar 3, 2009

Treating method and design method for tubular connections

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Quick Facts
Patent No.
US 7,497,481
App. No.
11/129,214
Granted
Mar 3, 2009
Kind
B2
Abstract

A method of treating a threaded connection that includes determining a treating time sufficient to form a thickness of a hopeite coating, coating at least a portion of the threaded connection with phosphating compound for a period of time sufficient to form the thickness of the hopeite coating is described.

Claims (9)

1. A threaded connection for oilfield tubulars, comprising:

a metal-to-metal seal, wherein the metal-to-metal seal has a diametral interference at a prescribed make-up between 0.0025″ and 0.0045″ per inch of nominal diameter of the oilfield tubulars; and

a zinc phosphate coating, wherein the zinc phosphate coating comprises particles having an average particle size of at least about 50 microns.

2. The threaded connection of claim 1 , wherein the metal-to-metal seal has a seal angle of less than 10 degrees.

3. The threaded connection of claim 1 , wherein the threaded connection has a thread pitch between 2 threads per inch and 6 threads per inch.

4. The threaded connection of claim 1 , wherein the oilfield tubulars have a nominal diameter of equal to or greater than 9.375″.

5. The threaded connection of claim 1 , wherein the zinc phosphate coating has a P-Ratio less than or equal to 0.6.

6. The threaded connection of claim 1 , wherein the zinc phosphate coating has a P-Ratio less than or equal to 0.4.

7. The threaded connection of claim 1 , wherein the average particle size ranges from about 50 to 100 microns.

Assignments (4)
CHANGE OF NAME Recorded Jan 7, 2011
From: HYDRIL LLC
To: HYDRIL COMPANY
Reel/Frame 025599/0988 →
MERGER Recorded Jan 5, 2009
From: HYDRIL COMPANY LP
To: HYDRIL GENERAL LLC
Reel/Frame 022057/0795 →
CHANGE OF NAME Recorded Jan 5, 2009
From: HYDRIL GENERAL LLC
To: HYDRIL LLC
Reel/Frame 022058/0226 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 26, 2006
From: REYNOLDS, JR., HARRIS A.
To: HYDRIL COMPANY LP
Reel/Frame 018732/0733 →