US3489620A - Method of processing sucker rods and resulting article - Google Patents

Method of processing sucker rods and resulting article Download PDF

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Publication number
US3489620A
US3489620A US619715A US3489620DA US3489620A US 3489620 A US3489620 A US 3489620A US 619715 A US619715 A US 619715A US 3489620D A US3489620D A US 3489620DA US 3489620 A US3489620 A US 3489620A
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United States
Prior art keywords
rod
case
rods
sucker
sucker rods
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Expired - Lifetime
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US619715A
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English (en)
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Farmer L Current
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OILWELL Inc A CORP OF
National Oilwell Varco LP
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United States Steel Corp
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Assigned to USX CORPORATION reassignment USX CORPORATION CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). EFFECTIVE JULY 9, 1986 Assignors: UNITED STATES STEEL CORPORATION
Assigned to OILWELL, INC., A CORP. OF DE reassignment OILWELL, INC., A CORP. OF DE ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: USX CORPORATION
Assigned to NATIONAL-OILWELL, A CORP. OF DE reassignment NATIONAL-OILWELL, A CORP. OF DE ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: OILWELL, INC.
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/0068—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for particular articles not mentioned below
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D7/00—Modifying the physical properties of iron or steel by deformation
    • C21D7/02—Modifying the physical properties of iron or steel by deformation by cold working
    • C21D7/04—Modifying the physical properties of iron or steel by deformation by cold working of the surface

Definitions

  • This invention relates to an improved method of processing sucker rods and to the resulting article.
  • sucker rods are rods which extend down a well for transmitting reciprocating motion from a pumping unit at the surface to a subsurface pump near the bottom.
  • the individual rods are connected end-to-end by internally threaded couplings, which engage externally threaded pins at the ends of the rods above and below.
  • a sucker rod string is subjected to cyclic loads as it moves up and down, and such loads often lead to fatigue failure. Corrosive attack by fluids in the well or abrasion of the rods against the well tubing may hasten such failure.
  • Hydrogen sulfide is present in most oil wells, and causes hydrogen embrittlement of sucker rods. It is known that sensitivity of carbon steel to hydrogen embrittlement greatly increases as the steel is hardened. Hydrogen ernbrittlement lowers the ability of steel to withstand tensile loads. Hence those skilled in the art would not expect any benefit to result from casehardening a sucker rod to combat fatigue failure, since the harder surface would lead to premature failure for other reasons.
  • An object of the present invention is to provide an improved sucker rod and processing method which significantly increase resistance of the rod against fatigue failure, yet avoid increasing its susceptibility to failure from other causes (e.g. hydrogen embrittlement).
  • a further object is to accomplish the foregoing object, and thus prolong the rod life, at reasonable cost.
  • a more specific object is to provide an improved rod and method in which a critical portion of the rod surface is subjected to a series of treatments including inductionhardening and further compressing, as by shot-peening, whereby resistance against fatigue failure is markedly enhanced.
  • FIGURE 1 is a side elevational view partly broken away of a portion of a sucker rod processed according to my invention
  • FIGURE 2 is a similar view showing a rod of modified construction.
  • FIGURE 3 is a similar view showing a rod of an other modified construction.
  • FIGURE 1 shows a sucker rod which includes an elongated body 10, and an enlarged elevator button 12 at the end of the body. Beyond the elevator button the rod includes in succession a wrench square 13, a pin shoulder 14, an undercut 15 and a threaded pin 16.
  • FIGURE 2 shows a sucker rod which has a rounded or bulbous elevator button 12a, but otherwise is of similar configuration to FIGURE 1.
  • FIGURE 3 shows a sucker rod, the wrench square 13a of which has rounded edges, but otherwise is of similar configuration to FIGURE 1.
  • the sucker rod is of steel, the preferred analysis of which is as follows:
  • High sulfur is undesirable, since it lowers the resistance of the rod to corrosion.
  • Surface decarburization of the rod should be avoided.
  • the carbon content at the surface should be at least 0.15 percent to achieve a stress pattern, as hereinafter described, and to enhance corrosion resistance.
  • I form the rod in a forging operation According to one procedure, I heat-treat the forged rod by austenitizing and cool it in air or quench it in liquid. I temper the rod, straighten it and remove scale from its surface. After processing the rod according to my invention, hereinafter described, I machine threads on the pins 16.
  • I heat the body 10 of the rod by induction and quench it to produce a substantially martensitic case 17.
  • a substantially martensitic case as a case which is free-of ferrite, but may contain a small amount of retained austenite.
  • the depth of case should be about 3 to 15 percent of the rod diameter, or preferably about 5 to 8 percent. A case depth less than about 3 percent is inadequate, while a case depth greater than about 15 percent makes the rod too brittle.
  • the case may extend the full length of the rod except for the threaded pins 16. However, with the form shown in FIGURE 1 I prefer to terminate the case at the plane where the elevator button 12 reaches its maximum diameter, or only slightly beyond with the elevator button 12a of FIGURE 2.
  • the wrench square 13a of FIGURE 3 can be uniformly casehardened more readily; hence with this form I prefer to extend the case to include the wrench square and into the pin shoulder 14.
  • the case hardness should be within the range of 400 to 800 Brinell or preferably 475 to 650.
  • I further compress the martensitic case (already in compression), preferably by shot-peening the rod surface.
  • I may advantageously peen the rod while it is at a slightly elevated temperature (up to about 300 F.).
  • the resulting thermal contraction adds to the compressive stress. This may also enhance the rate of dynamic strain aging and consequent pinning of dislocations.
  • the resulting compressive stress may be of any magnitude up to the elastic limit of the steel, but should be at least 40,000 p.s.i. My preferred range is about 60,000 to 125,000 p.s.i.
  • I may simply water-quench the forged rod from the red heat at which it comes off the upset machine.
  • the ends are unmachinable as water-quenched.
  • I heat the rod by induction I apply sufficient heat to temper the rod.
  • the substantially martensitic case is necessary to furnish the desired stress pattern without expensive alloys or expensive treatment, such as nitriding or carburizing.
  • the substantially martensitic case also improves the corrosion resistance of the rod, compared with a conventional rod which has a two-phase structure of iron carbide and ferrite.
  • the hardened surface of the rod might be expected to increase the sensitivity of the rod to hydrogen embrittlement, which would lower its ability to withstand tensile loads.
  • My invention overcomes this difiiculty by supplying additional compressive stress at the rod surface.
  • a method of processing a steel sucker rod the carbon content of which is at least 0.15% and which has threaded pins at each end comprising induction-hardening the rod apart from said pins to produce a substantially martensitic case of a depth about 3 to percent of the rod diameter and a hardness within the range of 400 to 800 Brinell, and further compressing said case to provide a stress of at least 40,000 p.s.i. up to the elastic limit of the steel.
  • the rod includes an enlarged elevator button, a wrench square and a pin shoulder between its body and pin, and said case terminates at said elevator button.
  • the rod includes an enlarged elevator button, a wrench square and a pin shoulder between its body and pin, and said case terminates at said shoulder.
  • a steel sucker rod the carbon content of which is at least 0.15% and which has threaded pins at its ends, the body of said rod apart from the pins having a substantially martensitic case of a depth about 3 to 15 percent of the rod diameter and a hardness within the range of 400 to 800 Brinell, said case being further compressed to provide a stress of at least 40,000 psi. up to the elastic limit of the steel.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Heat Treatment Of Articles (AREA)
  • Earth Drilling (AREA)
  • Forging (AREA)
  • Heat Treatment Of Steel (AREA)
US619715A 1967-03-01 1967-03-01 Method of processing sucker rods and resulting article Expired - Lifetime US3489620A (en)

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US61971567A 1967-03-01 1967-03-01

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US (1) US3489620A (en。)
JP (1) JPS4844632B1 (en。)
AT (1) AT292763B (en。)
BE (1) BE711435A (en。)
ES (1) ES350977A1 (en。)
FR (1) FR1557249A (en。)
GB (1) GB1198533A (en。)

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3661655A (en) * 1970-11-17 1972-05-09 North American Rockwell Metallic articles and the manufacture thereof
US4016015A (en) * 1972-10-31 1977-04-05 Centre De Recherches Metallurgiques-Centrium Voor Research In De Metallurgie Rolled steel rod or bar
US4026727A (en) * 1975-11-04 1977-05-31 A. Finkl & Sons Company Fatigue resistant steel, machinery parts and method of manufacture thereof
US4103800A (en) * 1977-04-28 1978-08-01 Lomax Donald P Backing material
US4131491A (en) * 1977-12-22 1978-12-26 Fmc Corporation Torsion bar and method of forming the same
US4318739A (en) * 1979-06-05 1982-03-09 A. Finkl & Sons Co. Steel having improved surface and reduction of area transverse properties, and method of manufacture thereof
US4319934A (en) * 1979-01-31 1982-03-16 Snap-On Tools Corporation Method of forming tools from alloy steel for severe cold forming
US4322247A (en) * 1979-01-31 1982-03-30 Snap-On Tools Corporation Alloy steel for severe cold forming
US4322256A (en) * 1979-01-31 1982-03-30 Snap-On Tools Corporation Tool made from alloy steel for severe cold forming
US4364772A (en) * 1981-05-28 1982-12-21 Titanium Metals Corporation Of America Rail wheel alloy
US4418259A (en) * 1981-08-21 1983-11-29 Park-Ohio Industries, Inc. Method and apparatus of uniform induction heating of an elongated workpiece
US4420667A (en) * 1982-06-21 1983-12-13 Park-Ohio Industries, Inc. Induction heating method and apparatus for elongated workpieces
US4433226A (en) * 1981-11-12 1984-02-21 Park-Ohio Industries, Inc. Method and apparatus for induction heating of an elongated workpiece
US4468261A (en) * 1982-04-26 1984-08-28 Woodings Robert T Method of normalizing sucker rods using a normalizing unloader
US4472207A (en) * 1982-03-26 1984-09-18 Kabushiki Kaisha Kobe Seiko Sho Method for manufacturing blank material suitable for oil drilling non-magnetic stabilizer
US4478652A (en) * 1982-07-09 1984-10-23 Woodings Robert T Class D sucker rods
US4482793A (en) * 1982-03-15 1984-11-13 Park-Ohio Industries, Inc. Apparatus for simultaneously heating a plurality of elongated workpieces
US4484833A (en) * 1981-09-30 1984-11-27 Consolidated Metal Products, Inc. Sucker rod
US4486249A (en) * 1982-07-09 1984-12-04 Woodings Robert T Method of making class D sucker rods
US5009000A (en) * 1988-09-28 1991-04-23 Scot Industries, Inc. Method for making sucker rod oil well pump
US5102479A (en) * 1990-08-10 1992-04-07 Daido Tokushuko K.K. High strength non-heat refining free cutting steels
US5362338A (en) * 1990-07-27 1994-11-08 Aichi Steel Works Ltd. Non-heat treating steel for hot forging
US5885522A (en) * 1996-09-12 1999-03-23 Midland Steel Products Co. Method and apparatus for heat treating and straightening structural members
US5928442A (en) * 1997-08-22 1999-07-27 Snap-On Technologies, Inc. Medium/high carbon low alloy steel for warm/cold forming
EP1001043A1 (en) * 1998-11-09 2000-05-17 Daido Tokushuko Kabushiki Kaisha Martensitic stainless steel parts and method for producing the same
US6374477B1 (en) * 1999-05-31 2002-04-23 Nsk, Ltd. Method for working input shaft for toroidal-type continuously variable transmission
WO2006026700A3 (en) * 2004-09-02 2006-05-04 Timken Co Optimization of steel metallurgy to improve broach tool life
US20060150384A1 (en) * 2002-06-28 2006-07-13 Weatherford Canada Partnership Method of manufacturing continuous sucker rod
EP1746177A1 (en) * 2005-07-22 2007-01-24 Nippon Steel Corporation High strength bolt excellent in delayed fracture resistance and method of production of same
US20160060968A1 (en) * 2014-08-29 2016-03-03 Wei Xie Sucker rod assembly
US9624736B1 (en) * 2016-03-04 2017-04-18 Tenaris Connections B.V. Sucker rod end
CN111451943A (zh) * 2020-04-14 2020-07-28 中国石油大学(华东) 一种空心抽油杆拉伸力施加装置及抛丸方法

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4415378A (en) * 1982-04-22 1983-11-15 Dana Corporation Case hardening method for steel parts
US4501942A (en) * 1982-09-09 1985-02-26 Park-Ohio Industries, Inc. Method and apparatus for uniform induction heating of an elongated workpiece
IT1176705B (it) * 1984-09-13 1987-08-18 Saipem Spa Procedimento perfezionato per l'indurimento superficiale dei giunti delle aste di perforazione e aste cosi' ottenute

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1690612A (en) * 1925-11-25 1928-11-06 Columbus Sucker Rod Company Method of making sucker rods
US1764068A (en) * 1927-01-08 1930-06-17 Emsco Derrick & Equip Co Steel sucker rod and the like and its production
US2281850A (en) * 1939-02-14 1942-05-05 Bethlehem Steel Corp Sucker rod steel

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1690612A (en) * 1925-11-25 1928-11-06 Columbus Sucker Rod Company Method of making sucker rods
US1764068A (en) * 1927-01-08 1930-06-17 Emsco Derrick & Equip Co Steel sucker rod and the like and its production
US2281850A (en) * 1939-02-14 1942-05-05 Bethlehem Steel Corp Sucker rod steel

Cited By (41)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3661655A (en) * 1970-11-17 1972-05-09 North American Rockwell Metallic articles and the manufacture thereof
US4016015A (en) * 1972-10-31 1977-04-05 Centre De Recherches Metallurgiques-Centrium Voor Research In De Metallurgie Rolled steel rod or bar
US4026727A (en) * 1975-11-04 1977-05-31 A. Finkl & Sons Company Fatigue resistant steel, machinery parts and method of manufacture thereof
US4103800A (en) * 1977-04-28 1978-08-01 Lomax Donald P Backing material
US4131491A (en) * 1977-12-22 1978-12-26 Fmc Corporation Torsion bar and method of forming the same
US4319934A (en) * 1979-01-31 1982-03-16 Snap-On Tools Corporation Method of forming tools from alloy steel for severe cold forming
US4322247A (en) * 1979-01-31 1982-03-30 Snap-On Tools Corporation Alloy steel for severe cold forming
US4322256A (en) * 1979-01-31 1982-03-30 Snap-On Tools Corporation Tool made from alloy steel for severe cold forming
US4318739A (en) * 1979-06-05 1982-03-09 A. Finkl & Sons Co. Steel having improved surface and reduction of area transverse properties, and method of manufacture thereof
US4364772A (en) * 1981-05-28 1982-12-21 Titanium Metals Corporation Of America Rail wheel alloy
US4418259A (en) * 1981-08-21 1983-11-29 Park-Ohio Industries, Inc. Method and apparatus of uniform induction heating of an elongated workpiece
US4484833A (en) * 1981-09-30 1984-11-27 Consolidated Metal Products, Inc. Sucker rod
US4433226A (en) * 1981-11-12 1984-02-21 Park-Ohio Industries, Inc. Method and apparatus for induction heating of an elongated workpiece
US4482793A (en) * 1982-03-15 1984-11-13 Park-Ohio Industries, Inc. Apparatus for simultaneously heating a plurality of elongated workpieces
US4472207A (en) * 1982-03-26 1984-09-18 Kabushiki Kaisha Kobe Seiko Sho Method for manufacturing blank material suitable for oil drilling non-magnetic stabilizer
US4468261A (en) * 1982-04-26 1984-08-28 Woodings Robert T Method of normalizing sucker rods using a normalizing unloader
US4420667A (en) * 1982-06-21 1983-12-13 Park-Ohio Industries, Inc. Induction heating method and apparatus for elongated workpieces
US4478652A (en) * 1982-07-09 1984-10-23 Woodings Robert T Class D sucker rods
US4486249A (en) * 1982-07-09 1984-12-04 Woodings Robert T Method of making class D sucker rods
US5009000A (en) * 1988-09-28 1991-04-23 Scot Industries, Inc. Method for making sucker rod oil well pump
US5362338A (en) * 1990-07-27 1994-11-08 Aichi Steel Works Ltd. Non-heat treating steel for hot forging
US5102479A (en) * 1990-08-10 1992-04-07 Daido Tokushuko K.K. High strength non-heat refining free cutting steels
US5885522A (en) * 1996-09-12 1999-03-23 Midland Steel Products Co. Method and apparatus for heat treating and straightening structural members
US5968293A (en) * 1996-09-12 1999-10-19 Midland Steel Products Co. Method and apparatus for heat treating and straightening structural members
US5928442A (en) * 1997-08-22 1999-07-27 Snap-On Technologies, Inc. Medium/high carbon low alloy steel for warm/cold forming
EP1001043A1 (en) * 1998-11-09 2000-05-17 Daido Tokushuko Kabushiki Kaisha Martensitic stainless steel parts and method for producing the same
US6374477B1 (en) * 1999-05-31 2002-04-23 Nsk, Ltd. Method for working input shaft for toroidal-type continuously variable transmission
US20130140345A1 (en) * 2002-06-28 2013-06-06 Weatherford / Lamb, Inc. Method of manufacturing continuous sucker rod
US8281472B2 (en) * 2002-06-28 2012-10-09 Weatherford Canada Partnership Method of manufacturing continuous sucker rod
US8839499B2 (en) * 2002-06-28 2014-09-23 Weatherford Canada Partnership Method of manufacturing continuous sucker rod
US20060150384A1 (en) * 2002-06-28 2006-07-13 Weatherford Canada Partnership Method of manufacturing continuous sucker rod
WO2006026700A3 (en) * 2004-09-02 2006-05-04 Timken Co Optimization of steel metallurgy to improve broach tool life
US20080095657A1 (en) * 2004-09-02 2008-04-24 The Timken Company Optimization Of Steel Metallurgy To Improve Broach Tool Life
US7510614B2 (en) 2005-07-22 2009-03-31 Nippon Steel Corporation High strength bolt excellent in delayed fracture resistance and method of production of same
US20070017610A1 (en) * 2005-07-22 2007-01-25 Suguru Yoshida High strength bolt excellent in delayed fracture resistance and method of production of same
EP1746177A1 (en) * 2005-07-22 2007-01-24 Nippon Steel Corporation High strength bolt excellent in delayed fracture resistance and method of production of same
US20160060968A1 (en) * 2014-08-29 2016-03-03 Wei Xie Sucker rod assembly
US9624736B1 (en) * 2016-03-04 2017-04-18 Tenaris Connections B.V. Sucker rod end
RU2730232C2 (ru) * 2016-03-04 2020-08-19 Тенарис Коннекшнс Б.В. Насосная штанга
CN111451943A (zh) * 2020-04-14 2020-07-28 中国石油大学(华东) 一种空心抽油杆拉伸力施加装置及抛丸方法
CN111451943B (zh) * 2020-04-14 2022-02-08 中国石油大学(华东) 一种空心抽油杆拉伸力施加装置及抛丸方法

Also Published As

Publication number Publication date
BE711435A (en。) 1968-07-01
AT292763B (de) 1971-09-10
GB1198533A (en) 1970-07-15
DE1608002A1 (de) 1970-10-22
JPS4844632B1 (en。) 1973-12-26
DE1608002B2 (de) 1975-08-07
ES350977A1 (es) 1969-12-01
FR1557249A (en。) 1969-02-14

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