US20180298459A1 - Online-control cooling process for seamless steel tube for effectively refining grains and the method for manufacturing thereof - Google Patents

Online-control cooling process for seamless steel tube for effectively refining grains and the method for manufacturing thereof Download PDF

Info

Publication number
US20180298459A1
US20180298459A1 US15/762,929 US201615762929A US2018298459A1 US 20180298459 A1 US20180298459 A1 US 20180298459A1 US 201615762929 A US201615762929 A US 201615762929A US 2018298459 A1 US2018298459 A1 US 2018298459A1
Authority
US
United States
Prior art keywords
seamless steel
steel tube
online
manufacturing
tube according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US15/762,929
Inventor
Yaoheng LIU
Zhonghua Zhang
Dongxing WU
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Baoshan Iron and Steel Co Ltd
Original Assignee
Baoshan Iron and Steel Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from CN201510615737.9A external-priority patent/CN105154765A/en
Priority claimed from CN201610265674.3A external-priority patent/CN105907937A/en
Application filed by Baoshan Iron and Steel Co Ltd filed Critical Baoshan Iron and Steel Co Ltd
Priority claimed from PCT/CN2016/099564 external-priority patent/WO2017050230A1/en
Assigned to BAOSHAN IRON & STEEL CO., LTD. reassignment BAOSHAN IRON & STEEL CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: LIU, Yaoheng, WU, Dongxing, ZHANG, ZHONGHUA
Publication of US20180298459A1 publication Critical patent/US20180298459A1/en
Abandoned legal-status Critical Current

Links

Classifications

    • 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
    • C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
    • C21D9/085—Cooling or quenching
    • 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
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/10—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies
    • C21D8/105—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies of ferrous alloys
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B19/00—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work
    • B21B19/02—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work the axes of the rollers being arranged essentially diagonally to the axis of the work, e.g. "cross" tube-rolling ; Diescher mills, Stiefel disc piercers or Stiefel rotary piercers
    • B21B19/04—Rolling basic material of solid, i.e. non-hollow, structure; Piercing, e.g. rotary piercing mills
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/74—Temperature control, e.g. by cooling or heating the rolls or the product
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/78—Control of tube rolling
    • 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
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • 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
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/62—Quenching devices
    • C21D1/667—Quenching devices for spray quenching
    • 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
    • C21D11/00—Process control or regulation for heat treatments
    • C21D11/005—Process control or regulation for heat treatments for cooling
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/005—Heat treatment of ferrous alloys containing Mn
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/008—Heat treatment of ferrous alloys containing Si
    • 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
    • C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
    • 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
    • C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
    • C21D9/48—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals deep-drawing sheets
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • 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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/002—Bainite
    • 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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/003—Cementite
    • 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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/005—Ferrite
    • 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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/008—Martensite
    • 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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/009—Pearlite
    • 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
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/10—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies

Definitions

  • the present invention relates to a controlled cooling process, in particular to an online control cooling process of a seamless steel tube.
  • the performance of the steel is directly influenced by the grain size. Fine grain strengthening is the only strengthening mechanism that improves both strength and toughness of the steel at the same time.
  • the cooling rate of a hot steel tube (austenitic state) is accelerated by means of blowing or spraying water, which increases the degree of widercooling of austenite, promotes the nucleation of ferrite, and helps to improve grain refinement and strength.
  • One of purposes of the present invention is to provide an online-control cooling process for effectively refining grain seamless steel tube.
  • the seamless steel tubes with good grain refinement can be obtained without adding large amount of alloying elements.
  • the present invention provides an online-control cooling process for seamless steel tube for effectively refining grains, comprising the following steps:
  • the method of on-line rapid cooling is not used to cool the steel pipe in the prior art, because this cooling method will cause the phase transition of hainite and martensitic, resulting in decreasing in toughness and elongation of the steel pipe.
  • the internal stress level of the seamless steel tube is much higher than those of offline re-heated austenitizing after the thermal deformation of the seamless steel tube, the seamless steel tube with online rapid cooling is likely to crack.
  • the inventors of the present invention conducted a lot of research and found that in order to make the grain significantly refined without the occurrence of phase transition of bainite or martensitic transformation, it is required to strictly control the quenching starting temperature, the final cooling temperature of quenching and the cooling rate, so as to coordinate with the element content of the steel effectively. Based on above, the inventors of the present invention propose said technical solution.
  • the temperature of the tube needs to be higher than the Ar3 temperature, this is because some proeutectoid ferrite forms in the seamless steel tube if the online-control cooling process for seamless steel tube begins at a temperature below Ar3, which will deteriorate the grain refined effect and performance of the seamless steel tube.
  • the continuous cooling of the tube is controlled from T1° C. to T2° C.
  • the cooling rate is lower than N1° C./s, subcooling of austenite is insufficient, on the other hand, when the cooling rate higher than N2° C./s, the steel tube is likely to crack. Therefore, in the online-control cooling process of the seamless steel tube according to the present invention, the cooling rate is controlled from N1° C./s to N2° C./s.
  • the Ar3 temperature is known to those skilled in the art or can be obtained under technical conditions. For example, it can be obtained by referring to a manual or by thermal simulation experiment.
  • C, Mn, Cr, Ni and Mo each represents the mass percentage of corresponding elements of the seamless steel tube. That is, the numerical values of C, Mn, Cr, Ni and Mo substituted into the equations are the numerical values before the percent %. For example, in one embodiment where C is 0.17% by mass, the substituted value of C into the equations is 0.17, rather than 0.0017. The substitution of other elements has same meaning and is not further described.
  • grains are further refined by setting a step of air-cooling after rapid cooling. Since a high undercooling degree of the austenite is formed during the rapid cooling in the air-cooling step of seamless steel tube, the cooling rate for air-cooling cannot be too fast. When the cooling rate of air-cooling exceeds 10° C./s, it brings significant phase transition of bainite. Therefore, in this technical solution, the cooling rate in air cannot exceed 10° C./s.
  • the total amount of alloying elements of the seamless steel tube is not more than 3% by mass, wherein alloying elements are at least one selected from C, Mn, Cr, Mo, Ni, Cu, V, Nb and Ti. If the alloying elements of the seamless steel tube exceed 3% by mass, the bainite/martensite phase can be obtained by air-cooling, to which said method cannot apply.
  • the alloying element of the seamless steel tube in the present technical solution is not limited to C, Mn, Cr, Mo, Ni, Cu, V, Nb and Ti, and may be other alloying elements.
  • the total amount of alloying elements of the seamless steel tube is 0.2% to 3% by mass.
  • the technical solution is particularly suitable for conventional carbon steel or low-alloy steel.
  • another purpose of the present invention is to provide a. method of manufacturing a seamless steel tube for effectively refining grains, comprising the steps of:
  • the implementation effect of effectively refining the grain is achieved by the online-control cooling process of the seamless steel tube described above.
  • the seamless steel tube can be austenitized without being reheated in the technical solution of the present invention, and the seamless steel tube has a better toughness by directly using online-control cooling process for the seamless steel tube.
  • the billet in step (1), can be produced by casting the smelted molten steel into a round billet, or can be produced by pouring first and then forging or rolling the slab into the billet.
  • step (2) the billet is heated to 1100 to 1130° C. and maintained for 1 to 4 hours, followed by piercing, rolling, stretch reducing or sizing, so as to obtain the tube.
  • another purpose of the present invention is to provide a seamless steel tube which is prepared by the method said above for manufacturing seamless steel tube.
  • the grain size grade thereof is at least 7.5.
  • the microstructure thereof is mainly in form of pearlite and ferrite, and the phase ratio of the pearlite and ferrite is not less than 80%.
  • the microstructure thereof further contains bainite and/or cementite.
  • the on-line control cooling process for the seamless steel tube according to the present invention can effectively refine the grains so that the grain size grade of the seamless steel tube obtained reaches at least 7.5.
  • the on-line control cooling process and the manufacturing method for the seamless steel tube according to the present invention can effectively improve the toughness of the steel pipe and greatly reduce the amount of addition of the alloying elements at the same performance level.
  • the on-line control of the cooling process and the manufacturing method for the seamless steel tube according to the present invention can avoid the cracking phenomenon of seamless steel tube which is unavoidable in the prior art and ensure the qualified rate of the product.
  • the Billet is heated to 1100° C. to 1130° C. and maintained for 1 to 4 hours, followed by piercing, rolling, stretch reducing or sizing, so as to obtain the tube.
  • Table 1 lists each mass percentage of the chemical elements of the seamless steel tubes of Example A1 to A7 and Comparative Example B1 to B6.
  • Table 2 lists the specific process parameters for the methods for manufacturing seamless steel tube of Example A1-A7 and Comparative Example B1-B6.
  • Cooling rate No. (° C.) (h) (° C.) (° C.) (° C.) (° C.) (° C.) (° C./s) (° C./s) in air/° C./s
  • A1 1280 2.8 835 930 616.8 731.8 654 41.4 105.84 61 3 A2 1140 3.5 865 920 698 813 724 39 100.8 42 5 A3 1260 2.5 865 920 698 813 735 39 100.8 73 1.5 A4 1150 1.4 865 970 698 813 728 39 100.8 55 1.8 A5 1250 2.5 721 780 578 693 660 31 84 38 8 A6 1200 2 790 940 583.15 698.15 625 39 100.8 52 6 A7 1240 2.5 750 900 669.2 784.2 694 43 109.2
  • Example A1-A7 and Comparative Example B1-B6 were processed into API arc-shaped samples.
  • the impact sample was test by the standard impact sample of the seamless steel tube of Example A1-A7 and Comparative Example B1 to B6 processed into 10 mm*10 mm*55 mm size, V-notch at 0° C.
  • the hardness after quenching cooling of each Example and Comparative Example was measured by a Rockwell hardness test.
  • the grain size was measured according to GB/T6394 standard after sampling, and the phase ratio was measured by the metallographic method.
  • the yield strength of the seamless steel tubes for all Example A1-A7 is ⁇ 336 MPa
  • the impact energy at 0° C. thereof is higher than 98J
  • the grain size grade is higher than 7.5
  • the phase ratio of the pearlite and ferrite in the microstructure of which is ⁇ 80%.
  • the component ratios of the chemical elements for all Example and Comparative Example have no difference, but the method for manufacturing of the Example and Comparative Example are significantly different. Therefore, the performance of the seamless tube of Example A1-A7 is superior to that of Comparative Example B1-B6 overall.
  • the quenching starting temperature of Comparative Example B1 is lower than the Ar3 temperature so that the steel of Comparative Example B1 precipitates proeutectoid ferrite, reducing its hardness after quenching and affecting the strength of seamless steel tube also.
  • the cooling rate of Comparative Example B2 is lower than the cooling rate range defined in the present technical solution, thus the desired microstructure could not be obtained, which will affect the performance.
  • the final cooling temperature of Comparative Example B3 was higher than the T2° C. of the present invention, thus the desired microstructure of seamless steel tube could not be obtained in Comparative Example B3, which will affect the performance.
  • the cooling rate of Comparative Example B4 is higher than the cooling rate range defined in the present technical solution, so that the steel tube cracked, the hardness is insufficient.
  • the final cooling temperature of Comparative Example 95 is lower than T1° C. as defined in the present technical solution, and the cooling rate in air of Comparative Example B6 is higher than the cooling rate range defined in the present technical solution, which results in a significant phase transition of bainite in Comparative Example B5 and Comparative Example B6, and lack of toughness.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Heat Treatment Of Steel (AREA)
  • Heat Treatment Of Articles (AREA)

Abstract

An online-control cooling process for seamless steel tube for effectively refining grains, comprising the following steps: when the temperature of a crude tube is higher than Ar3, evenly spraying water along the circumferential direction of the tube so as to continuously cool the tube to T1° C.˜T2° C., the cooling rate being controlled to be N1° C./s˜N2° C./s, wherein T1=810−360C−80(Mn+Cr)−37Ni−83Mo, T2=T1+115° C., N1=55-80×C, N2=168*(0.8−C), and C, Mn, Cr, Ni and Mo in the equations each represent the mass percentage of corresponding elements in the seamless steel tube; then, cooling to the room temperature at cooling rate no more than 10° C./s. Correspondingly, also provided are a method for manufacturing seamless steel tube for effectively refining grains, and a seamless steel tube. The online-control seamless steel tube cooling process does not require adding too many alloying elements, which is simple and can yield seamless steel tubes with good grain refinement and better toughness.

Description

    FIELD
  • The present invention relates to a controlled cooling process, in particular to an online control cooling process of a seamless steel tube.
    • BACKGROUND
  • In the prior art, due to product shape and manufacturing method limitations for hot-rolled seamless steel tubes, the product performance has long been improved only by addition of alloying elements and off-line heat treatment after rolling. Taking oil well tubes for example, tubes having a degree of 555 MPa (80 Ksi) or higher requires addition of more alloying elements in manufacturing, which significantly increases the manufacturing cost. Or, it can be made from conventional steel by off-line quenching heat treatment, wherein the so-called off-line quenching heat treatment means that hot-rolled seamless steel tubes are air-cooled to the room temperature after rolling, and be put into a tube bank firstly, then the pipes are heat-treated as needed. However, this method also complicates the process and increases the cost.
  • The performance of the steel is directly influenced by the grain size. Fine grain strengthening is the only strengthening mechanism that improves both strength and toughness of the steel at the same time. In general, the cooling rate of a hot steel tube (austenitic state) is accelerated by means of blowing or spraying water, which increases the degree of widercooling of austenite, promotes the nucleation of ferrite, and helps to improve grain refinement and strength.
  • Although those skilled in the art already know that on-line rapid cooling help the seamless steel tube obtain finer grain and better performance, the on-line rapid cooling is still not used in the prior art. This is because, cooling too fast will cause phase transition of bainite and martensite, although the strength of the seamless steel tube will increase significantly, rapid cooling often leads to great changes in material properties, such as decreasing in toughness and elongation, and increasing in yield ratio, etc. Such changes may not satisfy the requirements. On the other hand, the steel tube has a higher internal stress than that of sheet products due to its unique cross section, cooling too fast may lead to cracking and other problems.
  • Therefore, it is desired to obtain an online-control cooling process for seamless steel tube, which utilizes the waste heat after hot rolling of the steel pipe, wherein the online cooling process is controlled, grains are effectively refined and the toughness of seamless steel tube increases without non-equilibrium phase transition of bainite, martensite, etc.
    • Invention Contents
  • One of purposes of the present invention is to provide an online-control cooling process for effectively refining grain seamless steel tube. By using said process, the seamless steel tubes with good grain refinement can be obtained without adding large amount of alloying elements.
  • Based on the above invention purpose, the present invention provides an online-control cooling process for seamless steel tube for effectively refining grains, comprising the following steps:
  • when the temperature of tube is higher than Ar3, evenly spraying water along the circumferential direction of the tube so as to continuously cool the tube to temperature of T1° C.˜T2° C., the cooling rate being controlled to N1° C./s˜N2° C./s, wherein T1=810−360C−80(Mn+Cr)−37Ni−83Mo, T2=T1+115° C., N1=55−80×C, N2=168×(0.8−C), and C, Mn, Cr, Ni, and Mo in the equations each represents the mass percentage of corresponding elements of the seamless steel tube;
  • Then, cool the tube to the room temperature at a cooling rate no more than 10° C./s.
  • As already explained above, the method of on-line rapid cooling is not used to cool the steel pipe in the prior art, because this cooling method will cause the phase transition of hainite and martensitic, resulting in decreasing in toughness and elongation of the steel pipe. In addition, since the internal stress level of the seamless steel tube is much higher than those of offline re-heated austenitizing after the thermal deformation of the seamless steel tube, the seamless steel tube with online rapid cooling is likely to crack. In order to solve this technical problem, the inventors of the present invention conducted a lot of research and found that in order to make the grain significantly refined without the occurrence of phase transition of bainite or martensitic transformation, it is required to strictly control the quenching starting temperature, the final cooling temperature of quenching and the cooling rate, so as to coordinate with the element content of the steel effectively. Based on above, the inventors of the present invention propose said technical solution.
  • In this technical solution, the temperature of the tube needs to be higher than the Ar3 temperature, this is because some proeutectoid ferrite forms in the seamless steel tube if the online-control cooling process for seamless steel tube begins at a temperature below Ar3, which will deteriorate the grain refined effect and performance of the seamless steel tube.
  • In addition, the temperature of the continuous cooling of the tube is controlled from T1° C. to T2° C., wherein T1=T1=810−360C−80(Mn+Cr)−37Ni−83Mo and T2=T1+115° C. The inventors found that, a better implementation effect can be obtained when the final cooling temperature of the continuous cooling of the tube is controlled in the said range. When the final cooling temperature of the continuous cooling of the tube is higher than T2° C., the undercooling of the austenite is not enough, and the effect of the refining grains is not enough. When the final cooling temperature of the continuous cooling of the tube is lower than T1° C., the phase transition of bainite or martensite occurs and has an negative effect on the final performance of seamless steel tube. Therefore, in the said online-control cooling process for the seamless steel tube according to the present invention, the continuous cooling of the tube is controlled from T1° C. to T2° C.
  • Moreover, the inventors of the present invention also found that the seamless steel tube will obtain a better performance when the cooling rate is controlled from N1° C./s to N2° C./s, N1=55−80×C and N2=168×(0.8−C). When the cooling rate is lower than N1° C./s, subcooling of austenite is insufficient, on the other hand, when the cooling rate higher than N2° C./s, the steel tube is likely to crack. Therefore, in the online-control cooling process of the seamless steel tube according to the present invention, the cooling rate is controlled from N1° C./s to N2° C./s.
  • It should be noted that the Ar3 temperature is known to those skilled in the art or can be obtained under technical conditions. For example, it can be obtained by referring to a manual or by thermal simulation experiment.
  • In addition, it should be noted that, in the above equations, C, Mn, Cr, Ni and Mo each represents the mass percentage of corresponding elements of the seamless steel tube. That is, the numerical values of C, Mn, Cr, Ni and Mo substituted into the equations are the numerical values before the percent %. For example, in one embodiment where C is 0.17% by mass, the substituted value of C into the equations is 0.17, rather than 0.0017. The substitution of other elements has same meaning and is not further described.
  • It should also be noted that, the technical solution above which defines the above equations do not mean that the seamless steel tube must contain elements of C, Mn, Cr, Ni and Mo at the same time. The equations are general and can be applied to the seamless steel tube quenched by this method. Therefore, when one or more of the elements involved in the equations is not contained, zero should substitute into the equations.
  • In addition, in the present technical solution, grains are further refined by setting a step of air-cooling after rapid cooling. Since a high undercooling degree of the austenite is formed during the rapid cooling in the air-cooling step of seamless steel tube, the cooling rate for air-cooling cannot be too fast. When the cooling rate of air-cooling exceeds 10° C./s, it brings significant phase transition of bainite. Therefore, in this technical solution, the cooling rate in air cannot exceed 10° C./s.
  • Further, in the online-control cooling process for seamless steel tube according to the present invention, the total amount of alloying elements of the seamless steel tube is not more than 3% by mass, wherein alloying elements are at least one selected from C, Mn, Cr, Mo, Ni, Cu, V, Nb and Ti. If the alloying elements of the seamless steel tube exceed 3% by mass, the bainite/martensite phase can be obtained by air-cooling, to which said method cannot apply. In addition, the alloying element of the seamless steel tube in the present technical solution is not limited to C, Mn, Cr, Mo, Ni, Cu, V, Nb and Ti, and may be other alloying elements.
  • Further, in the online-control cooling process for seamless steel tube according to the present invention, the total amount of alloying elements of the seamless steel tube is 0.2% to 3% by mass.
  • The technical solution is particularly suitable for conventional carbon steel or low-alloy steel. By this process, seamless steel tube that meets performance requirements can be produced without adding excessive of alloying elements.
  • Accordingly, another purpose of the present invention is to provide a. method of manufacturing a seamless steel tube for effectively refining grains, comprising the steps of:
  • (1) manufacturing the Billet;
  • (2) forming the Billet into tube;
  • (3) cooling the tube by the online-control cooling process for seamless steel tube.
  • In the method for producing an effectively refined grain seamless steel tube according to the present invention, the implementation effect of effectively refining the grain is achieved by the online-control cooling process of the seamless steel tube described above. Compared with the prior art, the seamless steel tube can be austenitized without being reheated in the technical solution of the present invention, and the seamless steel tube has a better toughness by directly using online-control cooling process for the seamless steel tube.
  • It should be noted that, in step (1), the billet can be produced by casting the smelted molten steel into a round billet, or can be produced by pouring first and then forging or rolling the slab into the billet.
  • Further, in the manufacturing method for a seamless steel tube according to the present invention, in step (2), the billet is heated to 1100 to 1130° C. and maintained for 1 to 4 hours, followed by piercing, rolling, stretch reducing or sizing, so as to obtain the tube.
  • In addition, another purpose of the present invention is to provide a seamless steel tube which is prepared by the method said above for manufacturing seamless steel tube.
  • Further, in the seamless steel tube of the present invention, the grain size grade thereof is at least 7.5.
  • Further, in the seamless steel tube of the present invention, the microstructure thereof is mainly in form of pearlite and ferrite, and the phase ratio of the pearlite and ferrite is not less than 80%.
  • Further, in the seamless steel tube of the present invention, the microstructure thereof further contains bainite and/or cementite.
  • The online-control cooling process and the manufacturing method for the seamless steel tube for effectively refined grain according to the present invention have the following advantages and beneficial effects:
  • (1) The on-line control cooling process for the seamless steel tube according to the present invention can effectively refine the grains so that the grain size grade of the seamless steel tube obtained reaches at least 7.5.
  • (2) The on-line control cooling process and the manufacturing method for the seamless steel tube according to the present invention can effectively improve the toughness of the steel pipe and greatly reduce the amount of addition of the alloying elements at the same performance level.
  • (3) The on-line control of the cooling process and the manufacturing method for the seamless steel tube according to the present invention can avoid the cracking phenomenon of seamless steel tube which is unavoidable in the prior art and ensure the qualified rate of the product.
    • DETAILED DESCRIPTION
  • The online-control cooling process for the seamless steel tube for effectively refined grains according to the present invention will be further explained and described accompanying drawings and the specific Example as follow, and the this explanation and description shall not be deemed to limit to the technical solution of the present invention.
    • EXAMPLE A1-A7 AND COMPARATIVE EXAMPLE B1-B6
  • Seamless steel tubes in Example A1-A7 were manufactured according to the following steps:
  • (1) Manufacturing the Billet: smelting according to the mass percentage of each chemical element listed in Table 1, casting it into an ingot and forging the ingot into the Billet.
  • (2) forming the Billet into tube: the Billet is heated to 1100° C. to 1130° C. and maintained for 1 to 4 hours, followed by piercing, rolling, stretch reducing or sizing, so as to obtain the tube.
  • (3) using the online-control cooling process: when the temperature of tube is higher than Ar3, evenly spraying water along the circumferential direction of the tube so as to continuously cool the tube to temperature of T1° C.˜T2° C., the cooling rate being controlled to N1° C./s˜N2° C./s, wherein T1=810−360C−80(Mn+Cr)−37Ni−83Mo, T2=T1+115° C., N1=55−80×C, N2=168×(0.8−C), and C, Mn, Cr, Ni, and Mo in the equations each represents the mass percentage of corresponding elements of the seamless steel tube; then, cooling to the room temperature at a cooling rate no more than 10° C./s.
  • In order to demonstrate the implementation effect of the online-control cooling process of the present invention, the process steps of manufacturing the billet and the tube for Comparative Example B1-B6 are the same as that for Example of the invention, whereas the process parameters of control cooling process for Comparative Example B1-B6 are outside the protection scope of the present technical solution.
  • Table 1 lists each mass percentage of the chemical elements of the seamless steel tubes of Example A1 to A7 and Comparative Example B1 to B6.
  • TABLE 1
    (by wt %, the margin is Fe and other
    unavoidable impurity elements)
    Steel
    No. model C Mn Cr Mo Ni
    A1 16Mn 0.17 1.65 — — —
    A2 20# 0.2 0.5 — — —
    A3 20# 0.2 0.5 — — —
    A4 20# 0.2 0.5 — — —
    A5 30Mn2 0.3 1.55 — — —
    A6 20CrNi 0.2 0.55 0.9 — 1.05
    A7 15NiMo 0.15 0.6 0.2 0.60
    B1 16Mn 0.17 1.65 — — —
    B2 20# 0.2 0.5 — — —
    B3 20# 0.2 0.5 — — —
    B4 20# 0.2 0.5 — — —
    B5 20# 0.2 0.5 — — —
    B6 20# 0.2 0.5 — — —
  • Table 2 lists the specific process parameters for the methods for manufacturing seamless steel tube of Example A1-A7 and Comparative Example B1-B6.
  • TABLE 2
    Quenching Final
    Heating heating Ar3 starting cooling
    temperature time temperature temperature T1 T2 temperature N1 N2 Cooling rate Cooling rate
    No. (° C.) (h) (° C.) (° C.) (° C.) (° C.) (° C.) (° C./s) (° C./s) (° C./s) in air/° C./s
    A1 1280 2.8 835 930 616.8 731.8 654 41.4 105.84 61 3
    A2 1140 3.5 865 920 698 813 724 39 100.8 42 5
    A3 1260 2.5 865 920 698 813 735 39 100.8 73 1.5
    A4 1150 1.4 865 970 698 813 728 39 100.8 55 1.8
    A5 1250 2.5 721 780 578 693 660 31 84 38 8
    A6 1200 2 790 940 583.15 698.15 625 39 100.8 52 6
    A7 1240 2.5 750 900 669.2 784.2 694 43 109.2 75 4.6
    B1 1250 2 835
    Figure US20180298459A1-20181018-P00001
    		 616.8 731.8 628 41.4 105.84 48 2.5
    B2 1250 2 865 860 698 813 712 39 100.8
    Figure US20180298459A1-20181018-P00002
    		 4
    B3 1250 2 865 940 698 813
    Figure US20180298459A1-20181018-P00003
    		 39 100.8 46 5
    B4 1250 2 865 900 698 813 750 39 100.8
    Figure US20180298459A1-20181018-P00004
    		 8
    B5 1250 2 865 920 698 813
    Figure US20180298459A1-20181018-P00005
    		 39 100.8 42 5
    B6 1250 2 865 920 698 813 716 39 100.8 42
    Figure US20180298459A1-20181018-P00006
  • Various performance tests were conducted on the seamless steel tubes of Example A1-A7 and Comparative Example B1-B6, and the results are shown in Table 3. Wherein the yield strength data are average value obtained according to the API standard after the seamless steel tube of Example A1-A7 and the seamless steel tube of Comparative Example B1-B6 are processed into API arc-shaped samples. The impact sample was test by the standard impact sample of the seamless steel tube of Example A1-A7 and Comparative Example B1 to B6 processed into 10 mm*10 mm*55 mm size, V-notch at 0° C. In addition, the hardness after quenching cooling of each Example and Comparative Example was measured by a Rockwell hardness test. The grain size was measured according to GB/T6394 standard after sampling, and the phase ratio was measured by the metallographic method.
  • TABLE 3
    Performance data for each Example and each Comparative Example
    Impact
    energy Phase
    (full ratio
    Yield size Of
    Strength sample) Pearlite + Crack/
    Rp0.2 at 0° C. Grain ferrite yes
    No. (MPa) (J) size (%) or no
    A1 453 198 7.5 85 no
    A2 336 147 8 92 no
    A3 342 152 8 87 no
    A4 340 123 7.5 94 no
    A5 594 98 8 90 no
    A6 582 168 8.5 88 no
    A7 378 172 8.5 95 no
    B1 368 144 6 89 no
    B2 253 97 6.5 92 no
    B3 262 108 6.5 87 no
    B4 — — — — yes
    B5 428 16 6.5 24 no
    B6 359 32 5.5 31 no
  • As can be seen from Table 3, the yield strength of the seamless steel tubes for all Example A1-A7 is ≥336 MPa, the impact energy at 0° C. thereof is higher than 98J, and the grain size grade is higher than 7.5, and the phase ratio of the pearlite and ferrite in the microstructure of which is ≥80%.
  • As can be seen from Table 2 and Table 1, the component ratios of the chemical elements for all Example and Comparative Example have no difference, but the method for manufacturing of the Example and Comparative Example are significantly different. Therefore, the performance of the seamless tube of Example A1-A7 is superior to that of Comparative Example B1-B6 overall. in addition, as can be seen from Table 2 and Table 3, the quenching starting temperature of Comparative Example B1 is lower than the Ar3 temperature so that the steel of Comparative Example B1 precipitates proeutectoid ferrite, reducing its hardness after quenching and affecting the strength of seamless steel tube also. The cooling rate of Comparative Example B2 is lower than the cooling rate range defined in the present technical solution, thus the desired microstructure could not be obtained, which will affect the performance. The final cooling temperature of Comparative Example B3 was higher than the T2° C. of the present invention, thus the desired microstructure of seamless steel tube could not be obtained in Comparative Example B3, which will affect the performance. In addition, the cooling rate of Comparative Example B4 is higher than the cooling rate range defined in the present technical solution, so that the steel tube cracked, the hardness is insufficient. The final cooling temperature of Comparative Example 95 is lower than T1° C. as defined in the present technical solution, and the cooling rate in air of Comparative Example B6 is higher than the cooling rate range defined in the present technical solution, which results in a significant phase transition of bainite in Comparative Example B5 and Comparative Example B6, and lack of toughness.
  • It is to be noted that the above Example are only a specific embodiments of the present invention. Apparently, the invention is not limited to the above embodiments, and there are may be many similar variations. A person skilled in the art can directly derive or associate all the variations from the content disclosed by the invention, all of which shall be covered by the protection scope of the invention.

Claims (15)

1. An online-control cooling process for seamless steel tube for effectively refining grains, comprising the following steps:
spraying water evenly along the circumferential direction of the tube when the temperature of tube is higher than Ar3 so as to continuously cool the tube to temperature of T1° C.˜T2° C., and
controlling; the cooling rate to N1° C./s to N2° C./s, wherein

T1=810−360C−80(Mn+Cr)−37Ni−83Mo,

T2=T1+115° C.,

N1=55−80×C, and

N2=168×(0.8−C), and
wherein C, Mn, Cr, Ni, and Mo in the equations each represents the mass percentage of corresponding elements of the seamless steel tube; and
cooling to room temperature at a cooling rate no more than 10° C./s.
2. The online-control cooling process for seamless steel tube according to claim 1, wherein the total amount of alloying elements of the seamless steel tube is not more than 3% by mass, said alloying elements being at least one selected from the group consisting of C, Mn, Cr, Mo, Ni, Cu, V, Nb and Ti.
3. The online-control cooling process for seamless steel tube according to claim wherein the total amount of alloying elements of the seamless steel tube is 0.2% to 3% by mass.
4. A method for manufacturing seamless steel tube for effectively refining grains, comprising the following steps:
(1) manufacturing a billet;
(2) forming the billet into a tube;
(3) cooling the tube by the online-control cooling process for seamless steel tube according to claim 1.
5. The method for manufacturing seamless steel tube according to claim 4, wherein the obtained seamless steel tube has a grain size grade of at least 7.5.
6. The method for manufacturing seamless steel tube according to claim 4, wherein in step (2), the billet is heated to 1100° C. to 1130° C. and maintained for 1 to 4 hours, and further comprises piercing, rolling, stretch reducing or sizing, so as to obtain the tube.
7. A seamless steel tube, which is prepared by the method for manufacturing seamless steel tube according to claim 4.
8. The seamless steel tube according to claim 7, wherein the microstructure of steel is mainly in form of pearlite and ferrite, and the phase ratio of the pearlite and ferrite is not less than 80%.
9. The seamless steel tube according to claim 8, wherein the microstructure further contains bainite and/or cementite.
10. A seamless steel tube, which is prepare e od for manufacturing seamless steel tube according to claim 5.
11. The seamless steel tube according to claim 10, wherein the microstructure of steel is mainly in form of pearlite and ferrite, and the phase ratio of the pearlite and ferrite is not less than 80%.
12. The seamless steel tube according to claim 11, wherein the microstructure further contains bainite and/or cementite
13. A seamless steel tube, which is prepared by the method for manufacturing seamless steel tube according to claim 6.
14. The seamless steel tube according to claim 13, wherein the microstructure of steel is mainly in form of pearlite and ferrite, and the phase ratio of the pearlite and ferrite is not less than 80%.
15. The seamless steel tube according to claim 14, wherein the microstructure further contains bainite and/or cementite
US15/762,929 2015-09-24 2016-09-21 Online-control cooling process for seamless steel tube for effectively refining grains and the method for manufacturing thereof Abandoned US20180298459A1 (en)

Applications Claiming Priority (7)

Application Number Priority Date Filing Date Title
CN201510615737.9 2015-09-24
CN201510615737.9A CN105154765A (en) 2015-09-24 2015-09-24 Seamless steel tube with high strength and toughness and manufacturing method thereof
CN201610265674.3A CN105907937A (en) 2016-04-26 2016-04-26 Manufacturing method for bainite high-strength seamless steel tube and bainite high-strength seamless steel tube
CN201610265674.3 2016-04-26
CN201610784964.9A CN106555042A (en) 2015-09-24 2016-08-30 A kind of seamless steel pipe On-line Control cooling technique and manufacture method of effective crystal grain thinning
CN201610784964.9 2016-08-30
PCT/CN2016/099564 WO2017050230A1 (en) 2015-09-24 2016-09-21 Online-controlled seamless steel tube cooling process and seamless steel tube manufacturing method with effective grain refinement

Publications (1)

Publication Number Publication Date
US20180298459A1 true US20180298459A1 (en) 2018-10-18

Family

ID=58418385

Family Applications (4)

Application Number Title Priority Date Filing Date
US15/762,660 Active US11015232B2 (en) 2015-09-24 2016-09-21 Seamless steel tube with high strength and toughness and manufacturing method therefor
US15/762,929 Abandoned US20180298459A1 (en) 2015-09-24 2016-09-21 Online-control cooling process for seamless steel tube for effectively refining grains and the method for manufacturing thereof
US15/762,912 Active 2037-01-18 US11293072B2 (en) 2015-09-24 2016-09-21 Process for on-line quenching of seamless steel tube using residual heat and manufacturing method
US15/762,810 Active 2037-07-09 US11203794B2 (en) 2015-09-24 2016-09-21 Method for manufacturing bainite high-strength seamless steel tube, and bainite high-strength seamless steel tube

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US15/762,660 Active US11015232B2 (en) 2015-09-24 2016-09-21 Seamless steel tube with high strength and toughness and manufacturing method therefor

Family Applications After (2)

Application Number Title Priority Date Filing Date
US15/762,912 Active 2037-01-18 US11293072B2 (en) 2015-09-24 2016-09-21 Process for on-line quenching of seamless steel tube using residual heat and manufacturing method
US15/762,810 Active 2037-07-09 US11203794B2 (en) 2015-09-24 2016-09-21 Method for manufacturing bainite high-strength seamless steel tube, and bainite high-strength seamless steel tube

Country Status (4)

Country Link
US (4) US11015232B2 (en)
EP (4) EP3354756B1 (en)
JP (4) JP6586519B2 (en)
CN (4) CN106555045A (en)

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106555045A (en) * 2015-09-24 2017-04-05 宝山钢铁股份有限公司 A kind of seamless steel pipe press quenching cooling technique and manufacture method of utilization waste heat
CN109576568A (en) * 2017-09-28 2019-04-05 宝山钢铁股份有限公司 A kind of high-strength weldable casing and its manufacturing method
CN110317994B (en) * 2018-03-30 2021-12-17 宝山钢铁股份有限公司 Ultrahigh-strength steel for high heat input welding and manufacturing method thereof
CN110066907A (en) * 2019-02-16 2019-07-30 王翀 Lost foam casting high-chromium alloy wearing piece waste heat liquid is quenched processing method
TWI719750B (en) * 2019-12-10 2021-02-21 金允成企業股份有限公司 Forging and forming method of aluminum alloy pipe fittings
CN113637890B (en) * 2020-04-27 2022-06-28 宝山钢铁股份有限公司 Ultra-fine grain seamless steel pipe and manufacturing method thereof
CN111840659B (en) * 2020-04-30 2022-02-08 中科益安医疗科技（北京）股份有限公司 High-safety blood vessel support without nickel metal medicine elution and its making method
CN111850422B (en) * 2020-04-30 2022-01-11 中科益安医疗科技（北京）股份有限公司 High-nitrogen nickel-free austenitic stainless steel seamless thin-walled tube and preparation method thereof
CN111979382B (en) * 2020-09-03 2021-12-10 衡阳华菱钢管有限公司 Large-caliber thin-wall seamless steel pipe and preparation method thereof
CN112593061A (en) * 2020-11-18 2021-04-02 贵州鼎成熔鑫科技有限公司 Quenching and tempering method for hydraulic plunger pump and motor double-metal cylinder body spline
CN113458175A (en) * 2021-06-21 2021-10-01 周传盛 Spring steel processing method
CN113600637B (en) * 2021-06-30 2022-04-15 北京科技大学 Seamless steel pipe and preparation method thereof
CN114406005B (en) * 2022-04-01 2022-06-17 承德建龙特殊钢有限公司 Seamless steel pipe tracking production system one by one
CN114807526B (en) * 2022-04-13 2023-09-05 大冶特殊钢有限公司 Heat treatment method for large-size 45CrNiMoV medium-thick-wall seamless steel tube
CN115232941B (en) * 2022-07-25 2024-02-13 江苏沙钢集团有限公司 Method for reducing low-temperature brittle failure and martensite of high-carbon wire rod

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101829679A (en) * 2009-03-09 2010-09-15 鞍钢股份有限公司 Production method for producing shock toughness of pipe coupling material of hot rolled oil well

Family Cites Families (46)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5819439A (en) * 1981-07-28 1983-02-04 Sumitomo Metal Ind Ltd Production of high strength steel pipe having excellent low temperature toughness
JPS5819438A (en) * 1981-07-28 1983-02-04 Sumitomo Metal Ind Ltd Production of steel pipe having high strength and high toughness
JPS59150019A (en) * 1983-02-14 1984-08-28 Sumitomo Metal Ind Ltd Production of seamless steel pipe having high toughness
JPS6067623A (en) * 1983-09-21 1985-04-18 Kawasaki Steel Corp Preparation of high strength low carbon seamless steel pipe by direct hardening method
JP2967886B2 (en) 1991-02-22 1999-10-25 住友金属工業 株式会社 Low alloy heat resistant steel with excellent creep strength and toughness
JPH06145793A (en) * 1992-10-29 1994-05-27 Sumitomo Metal Ind Ltd Method for preventing decarburization of seamless steel tube
JPH0741855A (en) * 1993-07-26 1995-02-10 Nippon Steel Corp Production of low yield radio and high toughness seamless steel pipe showing metallic structure essentially consisting of fine-grained ferrite
JP3503211B2 (en) * 1994-09-30 2004-03-02 住友金属工業株式会社 Manufacturing method of high strength seamless steel pipe
JPH09235617A (en) * 1996-02-29 1997-09-09 Sumitomo Metal Ind Ltd Production of seamless steel tube
JP3262807B2 (en) * 1997-09-29 2002-03-04 住友金属工業株式会社 Oil well pipe steel and seamless oil well pipe with excellent resistance to wet carbon dioxide gas and seawater corrosion
JP3849438B2 (en) * 2001-03-09 2006-11-22 住友金属工業株式会社 Oil well steel pipe for expansion
JP2003013130A (en) 2001-06-26 2003-01-15 Sumitomo Metal Ind Ltd Method of manufacturing billet for producing steel pipe, and method of manufacturing steel pipe for line pipe
CN1208143C (en) * 2002-11-25 2005-06-29 宝山钢铁股份有限公司 Method for mfg of high-quality seamless steel pipe
JP4510677B2 (en) * 2005-03-28 2010-07-28 新日本製鐵株式会社 Steel pipe for ring gear material
JP4635764B2 (en) 2005-07-25 2011-02-23 住友金属工業株式会社 Seamless steel pipe manufacturing method
JP4945946B2 (en) * 2005-07-26 2012-06-06 住友金属工業株式会社 Seamless steel pipe and manufacturing method thereof
CN100494462C (en) 2006-05-30 2009-06-03 宝山钢铁股份有限公司 110Ksi grade CO2 H2S corrosion-proof oil well pipe and manufacturing method
CN1951589A (en) * 2006-11-21 2007-04-25 东北大学 A seamless steel pipe on-line cooling method
JP5020690B2 (en) 2007-04-18 2012-09-05 新日本製鐵株式会社 High strength steel pipe for machine structure and manufacturing method thereof
CN101328559B (en) * 2007-06-22 2011-07-13 宝山钢铁股份有限公司 Steel for low yield ratio petroleum case pipe, petroleum case pipe and manufacturing method thereof
CN100574916C (en) * 2007-11-16 2009-12-30 天津钢管集团股份有限公司 The process of hot rolled seamless steel tube On-line Control cooling
CN101658879A (en) * 2008-08-27 2010-03-03 宝山钢铁股份有限公司 Method for manufacturing seamless steel pipe
AR075976A1 (en) * 2009-03-30 2011-05-11 Sumitomo Metal Ind METHOD FOR THE MANUFACTURE OF PIPE WITHOUT SEWING
CN101928889A (en) 2009-06-23 2010-12-29 宝山钢铁股份有限公司 Steel for resisting sulfide corrosion and manufacturing method thereof
EP2530172B1 (en) * 2010-01-27 2018-03-14 Nippon Steel & Sumitomo Metal Corporation Production method for seamless steel pipe used in line pipe, and seamless steel pipe used in line pipe
JP4860786B2 (en) * 2010-03-05 2012-01-25 新日本製鐵株式会社 High-strength seamless steel pipe for machine structure with excellent toughness and its manufacturing method
FI20115702L (en) 2011-07-01 2013-01-02 Rautaruukki Oyj METHOD FOR PRODUCING HIGH-STRENGTH STRUCTURAL STEEL AND HIGH-STRENGTH STRUCTURAL STEEL
CN102618791B (en) * 2012-04-23 2014-08-06 天津商业大学 High strength and ductility oil casing with hydrogen sulfide corrosion resistance and manufacturing method for oil casing
BR112015004263A2 (en) * 2012-08-29 2017-07-04 Nippon Steel & Sumitomo Metal Corp seamless steel pipe and method for producing it
JP5928394B2 (en) * 2013-03-29 2016-06-01 Ｊｆｅスチール株式会社 Steel structure for hydrogen excellent in hydrogen embrittlement resistance in high-pressure hydrogen gas, hydrogen pressure accumulator, and method for producing hydrogen line pipe
AR096272A1 (en) * 2013-05-31 2015-12-16 Nippon Steel & Sumitomo Metal Corp SEAMLESS STEEL TUBE FOR DRIVING PIPES USED IN AGRICULTURAL ENVIRONMENTS
CN103290324A (en) * 2013-06-20 2013-09-11 衡阳华菱钢管有限公司 Fine-grain ferrite + pearlite type N80-1 non-quenched and tempered seamless oil bushing, and production method thereof
CN103741028B (en) * 2013-12-31 2016-04-13 攀钢集团成都钢钒有限公司 Low yield strength ratio low temperature weldless steel tube and production method thereof
CN103866203B (en) * 2014-01-15 2016-08-17 扬州龙川钢管有限公司 A kind of heavy caliber high-strength bridge seamless steel pipe and TMCP production method thereof
JP6225795B2 (en) 2014-03-31 2017-11-08 Ｊｆｅスチール株式会社 Manufacturing method of thick high-strength seamless steel pipe for line pipe with excellent resistance to sulfide stress corrosion cracking
JP6070617B2 (en) * 2014-04-03 2017-02-01 Ｊｆｅスチール株式会社 Seamless steel pipe for fuel injection pipes with excellent internal pressure fatigue resistance
CN103938094B (en) * 2014-04-28 2016-08-24 宝山钢铁股份有限公司 A kind of ultrahigh-intensity high-toughness petroleum casing pipe and manufacture method thereof
CN104294156B (en) * 2014-09-05 2016-06-08 武汉钢铁(集团)公司 A kind of economy the excellent high-carbon wear-resistant steel pipe of processing characteristics and production method
CN104831175B (en) * 2014-11-25 2017-09-29 宝鸡石油钢管有限责任公司 A kind of J55 grade of steels SEW expansion sleeves and its manufacture method
CA2970271C (en) * 2014-12-12 2020-02-18 Nippon Steel & Sumitomo Metal Corporation Low-alloy steel for oil well pipe and method of manufacturing low-alloy steel oil well pipe
MX2017008360A (en) * 2014-12-24 2017-10-24 Jfe Steel Corp High-strength seamless steel pipe for oil wells, and production method for high-strength seamless steel pipe for oil wells.
CN104878307A (en) * 2015-04-30 2015-09-02 内蒙古包钢钢联股份有限公司 Production method of bainite wear-resistance hot-rolled seamless steel pipe
CN105039863A (en) 2015-09-02 2015-11-11 山西太钢不锈钢股份有限公司 Manufacturing method of martensite stainless steel seamless tube for oil well
CN105154765A (en) * 2015-09-24 2015-12-16 宝山钢铁股份有限公司 Seamless steel tube with high strength and toughness and manufacturing method thereof
CN106555045A (en) * 2015-09-24 2017-04-05 宝山钢铁股份有限公司 A kind of seamless steel pipe press quenching cooling technique and manufacture method of utilization waste heat
CN105907937A (en) 2016-04-26 2016-08-31 宝山钢铁股份有限公司 Manufacturing method for bainite high-strength seamless steel tube and bainite high-strength seamless steel tube

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101829679A (en) * 2009-03-09 2010-09-15 鞍钢股份有限公司 Production method for producing shock toughness of pipe coupling material of hot rolled oil well

Also Published As

Publication number Publication date
JP6574307B2 (en) 2019-09-11
US20180265941A1 (en) 2018-09-20
EP3354755A1 (en) 2018-08-01
EP3354757A1 (en) 2018-08-01
CN106555107A (en) 2017-04-05
EP3354756A1 (en) 2018-08-01
EP3354756A4 (en) 2019-05-01
JP6586519B2 (en) 2019-10-02
CN106555113B (en) 2018-09-04
EP3354757A4 (en) 2019-03-13
US11293072B2 (en) 2022-04-05
JP2018532884A (en) 2018-11-08
EP3354763A1 (en) 2018-08-01
JP2018532883A (en) 2018-11-08
JP2018532885A (en) 2018-11-08
CN106555113A (en) 2017-04-05
JP2018534417A (en) 2018-11-22
EP3354756B1 (en) 2021-01-20
US20180274054A1 (en) 2018-09-27
US11203794B2 (en) 2021-12-21
EP3354763A4 (en) 2019-03-06
US20180282833A1 (en) 2018-10-04
JP6829717B2 (en) 2021-02-10
US11015232B2 (en) 2021-05-25
EP3354755A4 (en) 2019-03-06
CN106555107B (en) 2018-11-06
CN106555045A (en) 2017-04-05
EP3354755B1 (en) 2021-05-19
CN106555042A (en) 2017-04-05

Similar Documents

Publication Publication Date Title
EP3354756B1 (en) Online-controlled seamless steel tube cooling process and seamless steel tube manufacturing method with effective grain refinement
US10851432B2 (en) Ultra-high strength and ultra-high toughness casing steel, oil casing, and manufacturing method thereof
US11053563B2 (en) X80 pipeline steel with good strain-aging performance, pipeline tube and method for producing same
CN108368575B (en) Rolling wire rod for cold forging tempered product
CN106636943B (en) Elongation percentage A50.8>=48% thin gauge high tensile pipeline steel and its production method
CN101328559A (en) Steel for low yield ratio petroleum case pipe, petroleum case pipe and manufacturing method thereof
CN105154765A (en) Seamless steel tube with high strength and toughness and manufacturing method thereof
WO2017050227A1 (en) Seamless steel tube with high strength and toughness and manufacturing method therefor
WO2016063224A1 (en) An ultra-high strength thermo-mechanically processed steel
CN105063511B (en) Ultra-low carbon bainite thin gauge steel plate rolled through heavy and medium plate mill and production method of ultra-low carbon bainite thin gauge steel plate
CN107513669A (en) A kind of high-strength cold rolling square and rectangular pipe steel and its manufacture method
US20060219333A1 (en) Manufacturing method of seamless steel pipe for mechanical structural parts
WO2017050230A1 (en) Online-controlled seamless steel tube cooling process and seamless steel tube manufacturing method with effective grain refinement
CN107779744B (en) A kind of bainite type X100 grades of seamless line pipes and its manufacturing method
WO2017050229A1 (en) Process for on-line quenching of seamless steel tube using waste heat and manufacturing method
CN113637890B (en) Ultra-fine grain seamless steel pipe and manufacturing method thereof
JPS62263924A (en) Production of tough steel pipe
CN104630624A (en) Steel for high frequency welded J55 casing pipe, casing pipe and manufacturing method of casing pipe
CN113930675A (en) 2200 MPa-grade low-carbon B-free hot forming steel and preparation method thereof
WO2017050228A1 (en) Method for manufacturing bainite high-strength seamless steel tube, and bainite high-strength seamless steel tube

Legal Events

Date Code Title Description
AS Assignment

Owner name: BAOSHAN IRON & STEEL CO., LTD., CHINA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LIU, YAOHENG;ZHANG, ZHONGHUA;WU, DONGXING;REEL/FRAME:046137/0508

Effective date: 20180402

STPP Information on status: patent application and granting procedure in general

Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: FINAL REJECTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: ADVISORY ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION

STPP Information on status: patent application and granting procedure in general

Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER

STPP Information on status: patent application and granting procedure in general

Free format text: FINAL REJECTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: RESPONSE AFTER FINAL ACTION FORWARDED TO EXAMINER

STPP Information on status: patent application and granting procedure in general

Free format text: ADVISORY ACTION MAILED

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION