WO2010093034A1 - Method for producing metal tube - Google Patents

Method for producing metal tube Download PDF

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Publication number
WO2010093034A1
WO2010093034A1 PCT/JP2010/052165 JP2010052165W WO2010093034A1 WO 2010093034 A1 WO2010093034 A1 WO 2010093034A1 JP 2010052165 W JP2010052165 W JP 2010052165W WO 2010093034 A1 WO2010093034 A1 WO 2010093034A1
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WO
WIPO (PCT)
Prior art keywords
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metal tube
oxide scale
scale layer
mass
Prior art date
Application number
PCT/JP2010/052165
Other languages
French (fr)
Japanese (ja)
Inventor
西山　佳孝
正樹 上山
仁寿 豊田
Original Assignee
住友金属工業株式会社
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
Application filed by 住友金属工業株式会社 filed Critical 住友金属工業株式会社
Priority to JP2010506734A priority Critical patent/JP4586938B2/en
Priority to CA2750014A priority patent/CA2750014C/en
Priority to EP10741311.4A priority patent/EP2397573B1/en
Priority to CN2010800069933A priority patent/CN102308015A/en
Publication of WO2010093034A1 publication Critical patent/WO2010093034A1/en
Priority to US13/207,535 priority patent/US20110308669A1/en

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/02—Pretreatment of the material to be coated
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
    • B21C37/15—Making tubes of special shape; Making tube fittings
    • B21C37/20—Making helical or similar guides in or on tubes without removing material, e.g. by drawing same over mandrels, by pushing same through dies ; Making tubes with angled walls, ribbed tubes and tubes with decorated walls
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G75/00—Inhibiting corrosion or fouling in apparatus for treatment or conversion of hydrocarbon oils, in general
    • 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
    • C21D7/06—Modifying the physical properties of iron or steel by deformation by cold working of the surface by shot-peening or the like
    • 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
    • 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
    • C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
    • C21D9/14—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes wear-resistant or pressure-resistant pipes
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
    • C22C19/051—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W
    • C22C19/052—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being at least 40%
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
    • C22C19/051—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W
    • C22C19/053—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being at least 30% but less than 40%
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
    • C22C19/051—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W
    • C22C19/055—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being at least 20% but less than 30%
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
    • C22C19/058—Alloys based on nickel or cobalt based on nickel with chromium without Mo and W
    • 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
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/10—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of nickel or cobalt or alloys based thereon
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
    • C23C8/10—Oxidising

Definitions

  • the present invention relates to a method of manufacturing a metal tube having a scale layer at least on the inner surface.
  • the present invention relates to a method for manufacturing a metal tube having high strength at high temperatures and excellent corrosion resistance.
  • the metal pipe obtained by the present invention is a pipe used in a carburizing gas atmosphere containing hydrocarbon gas, CO gas or the like, for example, a cracking furnace pipe, a reforming furnace pipe, a heating furnace in an oil refinery, a petrochemical plant or the like. Suitable for use in tubes, heat exchanger tubes, etc.
  • the inner surface of the metal tube is exposed to a carburizing atmosphere. For this reason, it is preferable to form a Cr-based oxide scale layer on the inner surface of the metal tube to prevent carburization.
  • the oxide scale layer mainly composed of Cr has a high density and has an effect of shielding the penetration of carbon into the metal tube.
  • the Cr-based oxide scale layer has a small catalytic action against coking (carbon deposition). For this reason, it also has an effect of suppressing coking on the surface of the metal tube. As a result, the thermal conductivity to the fluid introduced into the metal tube can be maintained for a long time. Therefore, for example, when such a metal tube is used as a decomposition reaction tube, the yield of reaction products such as olefins is stabilized.
  • This Cr-based oxide scale layer is formed even in an environment where a metal tube is used.
  • carbon since carbon simultaneously enters the metal tube, it is difficult to uniformly form a Cr-based oxide scale layer on the inner surface of the metal tube. Therefore, it is effective to previously form an oxide scale layer mainly composed of Cr on the inner surface of the metal tube.
  • Patent Document 1 in order to prevent Ni from eluting from a steel pipe when a stainless steel pipe containing 12 to 20% by mass of Cr and 40% by mass or less of Ni is used in a high-temperature and high-pressure water environment, A method for forming a scale layer on the surface of a steel pipe by carrying out a heat treatment in which an atmosphere of 0.01 to 0.5% by volume of oxygen containing oxygen is heated to 800 to 1100 ° C. and held for 2 to 20 minutes Is disclosed.
  • Patent Document 2 discloses that the austenitic stainless steel stainless steel containing 14% by mass or less of Cr is heat-treated at 1100 ° C. or more by controlling the CO concentration in the barrel furnace to 150 ppm or more, and An invention for preventing scale unevenness due to abnormal oxidation is disclosed.
  • Patent Document 3 as a stainless steel used in a carburizing gas atmosphere, the Cr concentration in a Cr-deficient layer is 10% by mass or more on the surface of a base material containing 20 to 55% by mass of Cr, or further on the outside thereof.
  • An invention relating to stainless steel having a Cr-based oxide scale layer having a Cr content of 50% by mass or more is disclosed.
  • Patent Document 4 relates to a method for producing an ethylene cracking furnace tube excellent in coking resistance, in a tube containing 15 to 30% by mass of Cr and 15 to 50% by mass of Ni having a depth of at least 50 ⁇ m from the surface.
  • An invention is disclosed in which a cold working is performed, and then the tube is heated to 1100 ° C. or higher in an atmosphere of less than 5 vol% oxygen and 20 vol% nitrogen.
  • Stainless steel having an oxide scale layer as described in Patent Document 3 is excellent in carburization resistance and caulking resistance. However, in actual production, it is difficult to uniformly form a Cr-based oxide scale layer over the entire inner surface of the tube.
  • the austenite grain size having a depth of at least 30 ⁇ m from the surface layer is set to No. by cold working and nitrogen infiltration heat treatment.
  • 7 or more finely divided layers can improve the stability of the Cr 2 O 3 oxide film produced during use under actual operating conditions of 750 to 1100 ° C.
  • the oxide scale generated by the nitrogen infiltration heat treatment is removed, and a stable Cr 2 O 3 oxide film is formed on the finely divided layer in actual operation.
  • the present invention has been made to solve such problems of the prior art, and by forming a uniform Cr-based oxide scale layer on the inner surface of a metal tube, carburizing or coking from carburizing gas can be achieved.
  • An object of the present invention is to provide a method of manufacturing a metal tube having excellent resistance to the above.
  • the present invention has been made on the basis of such knowledge, and the gist thereof is a method for producing a metal tube as shown in the following (1) to (4).
  • a method of manufacturing a metal tube comprising forming a Cr-based oxide scale layer on at least the inner surface of the metal tube.
  • the metal tube is, by mass%, C: 0.01 to 0.6%, Si: 0.1 to 5%, Mn: 0.1 to 10%, P: 0.08% or less, S : 0.05% or less, Cr: 20 to 55%, Ni: 20 to 70%, N: 0.001 to 0.25% and O (oxygen): 0.02% or less,
  • the present invention it is possible to manufacture a metal tube having a Cr-based oxide scale layer uniformly on the inner surface of the metal tube.
  • the metal pipe obtained by the production method of the present invention is excellent in carburization resistance and coking resistance in a carburizing gas environment.
  • a metal tube having a predetermined chemical composition is mechanically treated and then subjected to a heat treatment for 0.5 to 60 minutes in a temperature range of 1050 to 1270 ° C.
  • a Cr-based oxide scale layer is formed on at least the inner surface of the film.
  • the metal tube used for the production method of the present invention needs to contain 20 to 55% Cr and 20 to 70% Ni.
  • the upper limit is made 55%.
  • the upper limit is preferably 35%. A more preferred range is 22 to 33%.
  • Ni is an element necessary for obtaining a stable austenite structure. Ni is contained in an appropriate amount according to the Cr content. Ni has a function of reducing the penetration rate of carbon into the metal material. These effects are exhibited when the content is 20% or more. However, these effects saturate even when Ni is added excessively, thus increasing the manufacturing cost. Excessive Ni makes tube manufacture difficult. Therefore, the Ni content is 20 to 70%. A preferred lower limit is 23% and a preferred upper limit is 60%. A more preferred upper limit is 50%.
  • the material for the metal tube for ethylene production preferably contains Cr: 20 to 35% and Ni: 20 to 60%.
  • the metal tube used in the production method of the present invention has the above-described chemical composition, and there are no particular restrictions on the other components.
  • C 0.01 to 0.6%, Si: 0.1 -5%, Mn: 0.1-10%, P: 0.08% or less, S: 0.05% or less, Cr: 20-55%, Ni: 20-70%, N: 0.001-0 .25% and O (oxygen): 0.02% or less is preferable, and the remainder has a chemical composition composed of Fe and impurities.
  • C 0.01 to 0.6%
  • Si 0.1 -5%
  • Mn 0.1-10%
  • P 0.08% or less
  • S 0.05% or less
  • Cr 20-55%
  • Ni 20-70%
  • N 0.001-0 .25%
  • O (oxygen): 0.02% or less is preferable
  • the remainder has a chemical composition composed of Fe and impurities.
  • O oxygen
  • Impurity means a component mixed from ore, scrap and the like when industrially producing a metal tube, and is allowed within a range that does not adversely affect the present invention.
  • C 0.01 to 0.6%
  • C is an element effective for ensuring high temperature strength. This effect becomes remarkable when C is contained by 0.01% or more.
  • the content exceeds 0.6%, the toughness may be extremely deteriorated. Therefore, the C content is preferably 0.01 to 0.6%.
  • a more preferred lower limit is 0.02%.
  • a more preferred upper limit is 0.45%.
  • a more preferred upper limit is 0.3%.
  • Si 0.1 to 5% Since Si has a strong affinity for oxygen, it has the effect of promoting uniform formation of a Cr-based oxide scale layer. This effect becomes significant when the content is 0.1% or more. However, if its content exceeds 5%, the weldability deteriorates and the structure may become unstable. Accordingly, the Si content is preferably 0.1 to 5%. A preferable upper limit is 3%, and a more preferable upper limit is 2%. A more preferred lower limit is 0.3%.
  • Mn 0.1 to 10%
  • Mn is an element effective for deoxidation and effective for improving workability. Further, since Mn is an austenite generating element, a part of Ni can be replaced with Mn. In order to acquire these effects, it is preferable to make it contain 0.1% or more. However, if excessively contained, the formation of a Cr-based oxide scale layer may be hindered. Accordingly, the Mn content is preferably 0.1 to 10%. A preferable upper limit is 5%, and a more preferable upper limit is 2%.
  • P 0.08% or less
  • S 0.05% or less
  • P and S are preferably segregated at the crystal grain boundaries and deteriorated in hot workability.
  • P is 0.08% or less and S is 0.05% or less.
  • P is 0.05% or less and S is 0.03% or less.
  • P is 0.04% or less, and S is 0.015% or less.
  • N 0.001 to 0.25%
  • N is an element effective for improving the high-temperature strength. This effect becomes remarkable when the content is 0.001% or more. However, excessive addition may greatly impair processability. Therefore, the N content is preferably 0.001 to 0.25%. A preferable upper limit is 0.2%.
  • Oxygen (O) is an element present as an impurity.
  • oxygen content exceeds 0.02%, a large amount of oxide inclusions are precipitated in the metal material, the workability is lowered, and the surface flaw of the tube is caused. Therefore, the oxygen content is preferably 0.02% or less.
  • the metal tube may further contain one type selected from the elements listed in the following (a) to (g).
  • Cu is an element that stabilizes the austenite phase. Cu is also an element effective for improving the high-temperature strength. Therefore, Cu may be contained in the metal tube. However, when the content is excessive, hot workability may be reduced. Therefore, when Cu is contained, the content is preferably 5% or less. A more preferred upper limit is 3%. Said effect becomes remarkable when it contains 0.1% or more.
  • Co is an element that stabilizes the austenite phase. If Co is contained, a part of Ni can be substituted. Therefore, Co may be contained in the metal tube. However, when the content is excessive, hot workability may be reduced. Therefore, when Co is contained, the content is preferably 5% or less. A more preferred upper limit is 3%. Said effect becomes remarkable when it contains 0.1% or more.
  • Mo 3% or less
  • W 6% or less
  • Ta 6% or less
  • Mo, W, and Ta are all elements that contribute to solid solution strengthening and improve high-temperature strength. It is valid. Therefore, one or more selected from these elements may be contained in the metal tube. However, when the content is excessive, the workability is deteriorated and the tissue stability may be impaired. Therefore, when one or more of these elements are contained, Mo is preferably 3% and W and Ta are preferably 6% or less. A preferable upper limit of these elements is 2.5%. A more preferred upper limit is 2%. In any element, the above effect becomes remarkable when 0.01% or more is contained. Moreover, when these are compounded and contained, it is preferable to make the upper limit of the total amount into 10%.
  • Ti and Nb have a great effect in improving high-temperature strength, ductility and toughness even if contained in a very small amount. Therefore, one or two selected from these elements may be contained in the metal tube. However, when these elements are contained excessively, workability and weldability may be deteriorated. Therefore, when one or two of these elements are contained, Ti is preferably 1% or less and Nb is preferably 2% or less. In any element, the above effect becomes remarkable when 0.01% or more is contained. Moreover, when these are compounded and contained, it is preferable to make the upper limit of the total amount into 2%.
  • B 0.1% or less, Zr: 0.1% or less, and Hf: 0.5% or less
  • B, Zr, and Hf all strengthen grain boundaries and are hot Since it is an effective element for improving workability and high-temperature strength characteristics, one or more selected from these elements may be contained in the metal tube. However, if the content of any element is excessive, the weldability may be deteriorated. Therefore, when one or more of these elements are contained, the B and Zr contents are preferably 0.1% or less, and the Hf content is preferably 0.5% or less. In any element, the above effect becomes remarkable when 0.001% or more is contained. Moreover, when these are compounded and contained, it is preferable to make the upper limit of the total amount into 0.3%.
  • Mg: 0.1% or less, Ca: 0.1% or less, and Al: 1% or less Mg, Ca, and Al are all effective in improving hot workability Element. Therefore, you may make 1 or more types selected from these elements contain in said metal pipe. However, when the content of these elements is excessive, the weldability may be deteriorated. Therefore, when one or more of these elements are contained, the Mg content is preferably 0.1% or less, the Ca content is 0.1% or less, and the Al content is 1% or less. A more preferable upper limit is 0.05% for Mg and Ca, and 0.6% for Al. In addition, said effect becomes remarkable when it contains 0.001% or more in Mg and Ca, and 0.01% or more in Al. A more preferred lower limit is 0.002% for Mg and Ca. Moreover, when these are compounded and contained, it is preferable to make the upper limit of the total amount into 0.5%.
  • Y and Ln group are effective elements for improving oxidation resistance. Therefore, you may make 1 or more types selected from these elements contain in said metal pipe. When the content of any element is excessive, workability is reduced. Therefore, when one or more of these elements are contained, the content is preferably 0.15% or less. In addition, said effect becomes remarkable when it contains 0.0005% or more in any element.
  • the upper limit of the preferable content is 0.10% or less. Moreover, when these are compounded and contained, it is preferable to make the upper limit of the total amount into 0.15%.
  • the Ln group means from La of element number 57 to Lu of element 71. Among Ln groups, it is particularly preferable to use one or more of La, Ce and Nd.
  • a lubricant is used to reduce the friction between the metal tube and the processing tool.
  • the lubricant is usually removed by degreasing and washing after processing. However, a part of the lubricant remains on the inner surface of the pipe.
  • a mechanical treatment is performed to remove this.
  • oxidized scale, dirt, etc. generated during hot pipe production may adhere and remain on the surface of the metal pipe. These residues are preferably removed because they inhibit the uniform formation of the Cr-based oxide scale layer.
  • the mechanical treatment is a treatment for enhancing the surface cleanliness by physically removing deposits such as lubricant, dirt and oxide scale remaining on the surface of the metal tube.
  • the mechanical treatment include a blasting treatment, a grinding treatment (or friction treatment) in which an abrasive is directly brought into contact with the inner surface of the metal tube and removed by rubbing, and a method in which high pressure water is sprayed and removed without the abrasive. It is done.
  • the blast treatment for example, air blast for projecting a projection material with compressed air, sand blasting using sand as a projection material (a type of air blasting), and projection material is projected by centrifugal force of an impeller made of wear-resistant alloy.
  • shot blasting shot peening (a kind of shot blasting) whose main purpose is to impart strain to the metal surface, wet blasting and the like. Shot peening can remove surface deposits at the same time as applying strain.
  • wet blasting in which the projection material is projected with high-pressure water can also be applied.
  • the abrasive used for the mechanical treatment is not particularly limited.
  • abrasives which consist of metals, such as cast steel, stainless steel, metal glass (amorphous), and Cr.
  • the average particle diameter is preferably 300 ⁇ m or less, and most preferably 150 ⁇ m or less.
  • the abrasive on the inner surface of the pipe When spraying the abrasive on the inner surface of the pipe at high speed, it may be sprayed from one end or both ends of the metal pipe, or may be sprayed by inserting a spray nozzle into the metal pipe and moving in the pipe.
  • the abrasive or the non-woven fabric to which the abrasive is fixed may be dried or wetted with a liquid to directly contact the inner surface of the metal tube and move while rubbing.
  • the metal tube subjected to the mechanical treatment is subjected to heat treatment, and a Cr-based oxide scale layer is formed on the inner surface of the metal tube.
  • the heat treatment temperature is less than 1050 ° C.
  • the oxide scale layer formed on the surface of the metal tube is thin, and the shielding property against penetration of carbon into the metal material is not sufficient.
  • the temperature exceeds 1270 ° C.
  • pores and cracks are generated in the oxide scale layer, and as a result, the density decreases, and the carburization resistance decreases. Therefore, the heat treatment was performed in the temperature range of 1050 to 1270 ° C.
  • a preferred lower limit is 1120 ° C, and more preferred is 1160 ° C.
  • the holding time of the heat treatment is less than 0.5 minutes, a Cr-based oxide scale layer having excellent carburization resistance cannot be formed uniformly.
  • the holding time exceeds 60 minutes, only the thickness of the oxide scale layer is increased, resulting in a decrease in productivity and an increase in energy cost.
  • the density of the oxide scale layer is lowered. Therefore, the holding period in the above temperature range is set to 0.5 to 60 minutes.
  • the preferred lower limit is 2 minutes, and more preferred is 5 minutes.
  • the preferred upper limit is 30 minutes, and more preferred is 15 minutes.
  • the gas atmosphere in the heat treatment may be any conditions that can form a Cr-based oxide scale layer.
  • it is an atmosphere such as atmospheric gas, a gas obtained by burning hydrocarbon fuel (LNG, butane, etc.) and air.
  • the atmosphere may be DX gas, NX gas, RX gas, COG (C gas), hydrogen gas with a controlled dew point, or the like.
  • a gas atmosphere in which these gases are mixed at an arbitrary ratio may be used.
  • Cr-based oxide scale layer The Cr-based oxide scale layer is very important from the viewpoint of carburization resistance and coking resistance.
  • an oxide scale layer containing 50% or more of Cr has a high density and a high shielding property against penetration of carbon into the metal material. Since the Cr-based oxide scale layer has a small catalytic effect on coking, it suppresses coking on the surface of the metal material. As a result, the thermal conductivity to the fluid in the pipe is maintained for a long time. For example, when used as a decomposition reaction tube, the yield of reaction products such as olefins is stabilized.
  • the Cr content in the oxide scale layer is preferably 80% or more.
  • the oxide scale layer having a high Cr content is denser and exhibits a strong shielding effect against the penetration of carbon into the metal material.
  • the element content in the oxide scale layer can be measured by EDX. The measurement may be performed from the surface of the oxide scale layer. The quantification of the element is determined by the fraction of the detection element excluding C (carbon), O (oxygen) and the like.
  • the present invention is particularly useful when manufacturing a metal tube having rib-like projections on the inner surface.
  • a metal tube having rib-like protrusions on its inner surface it is considered that it is easily attacked by a carburizing gas, and oxide scale peeling is likely to occur.
  • a tube having a rib-like projection on the inner surface of the tube a tube with an inner projection, a finned tube, and the like can be given.
  • the protrusions, fins, etc. may be formed integrally with the tube itself or may be formed by welding or the like.
  • a metal material having the chemical composition shown in Table 1 was melted using an electric furnace or a vacuum melting furnace to form a billet.
  • the obtained billet was hot forged and cold rolled to produce a metal tube having an outer diameter of 56 mm and a wall thickness of 6 mm.
  • Mechanical treatment under the conditions shown in Table 2 was performed on the metal tubes of specimen numbers 1 to 10. Some omitted mechanical processing. These were heat-treated under the conditions described in Table 2 to form oxide scales. Some performed alumina blasting as a mechanical treatment and no heat treatment.
  • a total of five locations are cut at a pitch of 2 m from the longitudinal direction of the tube, and a ring-shaped test piece having a width of 50 mm and an oxide scale observation test piece to be described later. (20 ⁇ 20 mm square) was collected.
  • the ring-shaped test piece was held at 1000 ° C. for 300 hours in a gas atmosphere of 15% CH 4 -3% CO 2 -82% H 2 by volume to perform carburization and coking tests.
  • the coking resistance the mass of the test piece before and after the test was measured, the increase due to the coke deposition was determined, and the amount of deposited coke per unit area (mg / cm 2 ) was determined.
  • the carburization resistance was evaluated by the amount of C entering the base material.
  • the numbers in Table 2 indicate the numbers satisfying each of the above (1), (2) and (3) for five test pieces for each condition. For example, 3/5 out of 5 passes.
  • the entire length of the inner surface of the metal tube is intended to be excellent in carburization resistance and caulking resistance. Therefore, it was judged that the case where all five passed satisfied the standard of the present invention.
  • the metal pipe obtained by the present invention is a pipe used in a carburizing gas atmosphere containing hydrocarbon gas, CO gas, etc., for example, a cracking furnace pipe in a petroleum refining, petrochemical plant, etc., reforming Suitable for use as furnace tube, heating furnace tube, heat exchanger tube and the like.

Abstract

Provided is a method for producing a metal tube which has excellent carburization resistance and coking resistance in a carburizing gas atmosphere.  The inner surface of a metal tube containing 20 to 55% by mass of Cr and 20 to 70% by mass of Ni is subjected to a mechanical treatment, followed by a thermal treatment in a temperature range from 1050 to 1270ºC for 0.5 to 60 minutes, whereby an oxide scale layer containing mainly Cr is formed at least on the inner surface of the metal tube.

Description

金属管の製造方法Metal tube manufacturing method
　この発明は、少なくとも内面にスケール層を有する金属管の製造方法に関する。この発明は、特に、高温強度が高く、耐食性に優れる金属管の製造方法に関する。本発明によって得られる金属管は、炭化水素ガス、ＣＯガス等を含有する浸炭性ガス雰囲気で使用される管、例えば、石油精製、石油化学プラントなどにおける分解炉管、改質炉管、加熱炉管、熱交換器管等に用いるのに適している。 The present invention relates to a method of manufacturing a metal tube having a scale layer at least on the inner surface. In particular, the present invention relates to a method for manufacturing a metal tube having high strength at high temperatures and excellent corrosion resistance. The metal pipe obtained by the present invention is a pipe used in a carburizing gas atmosphere containing hydrocarbon gas, CO gas or the like, for example, a cracking furnace pipe, a reforming furnace pipe, a heating furnace in an oil refinery, a petrochemical plant or the like. Suitable for use in tubes, heat exchanger tubes, etc.
近年、例えば、石油精製、石油化学プラントなど、炭化水素ガス、ＣＯガスなどを含有する浸炭性ガス雰囲気で使用される分解炉管、改質炉管、加熱炉管、熱交換器管などには、Ｃｒを２０～３５質量％およびＮｉを２０～７０質量％含有する金属管が用いられるようになってきている。この金属管は、高温強度および耐食性に優れるからである。 Recently, for example, cracking furnace tubes, reforming furnace tubes, heating furnace tubes, heat exchanger tubes, etc. used in carburizing gas atmospheres containing hydrocarbon gas, CO gas, etc., such as petroleum refining and petrochemical plants Metal tubes containing 20 to 35% by mass of Cr and 20 to 70% by mass of Ni have been used. This is because this metal tube is excellent in high temperature strength and corrosion resistance.
　金属管の内面は、浸炭性雰囲気に曝される。このため、金属管の内面には浸炭防止のためにＣｒ主体の酸化スケール層を形成するのが好ましい。Ｃｒ主体の酸化スケール層は、緻密度が高く、炭素の金属管への侵入を遮蔽する効果を有している。Ｃｒ主体の酸化スケール層は、コーキング（炭素の堆積）に対して触媒作用が小さい。このため、金属管表面へのコーキングを抑制する効果も有している。その結果、金属管内に導入される流体への熱伝導性を長時間保つことができる。従って、例えば、そのような金属管を分解反応管として用いた場合、オレフィンなどの反応生成物の収率が安定する。このＣｒ主体の酸化スケール層は、金属管が使用される環境においても形成される。しかしながら、上記のように、金属管には同時に炭素が侵入するため、金属管内面に均一にＣｒ主体の酸化スケール層を形成させるのは困難である。そのため、金属管内面には、予めＣｒ主体の酸化スケール層を形成しておくのが有効である。 The inner surface of the metal tube is exposed to a carburizing atmosphere. For this reason, it is preferable to form a Cr-based oxide scale layer on the inner surface of the metal tube to prevent carburization. The oxide scale layer mainly composed of Cr has a high density and has an effect of shielding the penetration of carbon into the metal tube. The Cr-based oxide scale layer has a small catalytic action against coking (carbon deposition). For this reason, it also has an effect of suppressing coking on the surface of the metal tube. As a result, the thermal conductivity to the fluid introduced into the metal tube can be maintained for a long time. Therefore, for example, when such a metal tube is used as a decomposition reaction tube, the yield of reaction products such as olefins is stabilized. This Cr-based oxide scale layer is formed even in an environment where a metal tube is used. However, as described above, since carbon simultaneously enters the metal tube, it is difficult to uniformly form a Cr-based oxide scale layer on the inner surface of the metal tube. Therefore, it is effective to previously form an oxide scale layer mainly composed of Cr on the inner surface of the metal tube.
　特許文献１には、Ｃｒを１２～２０質量％とＮｉを４０質量％以下含有するステンレス鋼管が高温高圧水環境下で使用されるときに、鋼管からＮｉが溶出するのを防止するため、予め、０．０１～０．５体積％の酸素を含む不活性ガス雰囲気下で、８００～１１００℃に加熱し、２～２０分保持する熱処理を実施して、鋼管表面にスケール層を形成させる方法が開示されている。また、特許文献２には、１４質量％以下のＣｒを含有するオーステナイト系ステンレス鋼ステンレス鋼を、バレル炉内のＣＯ濃度を１５０ｐｐｍ以上に管理して１１００℃以上で熱処理することにより、鋼表面の異常酸化によるスケールむらを防止する発明が開示されている。 In Patent Document 1, in order to prevent Ni from eluting from a steel pipe when a stainless steel pipe containing 12 to 20% by mass of Cr and 40% by mass or less of Ni is used in a high-temperature and high-pressure water environment, A method for forming a scale layer on the surface of a steel pipe by carrying out a heat treatment in which an atmosphere of 0.01 to 0.5% by volume of oxygen containing oxygen is heated to 800 to 1100 ° C. and held for 2 to 20 minutes Is disclosed. Patent Document 2 discloses that the austenitic stainless steel stainless steel containing 14% by mass or less of Cr is heat-treated at 1100 ° C. or more by controlling the CO concentration in the barrel furnace to 150 ppm or more, and An invention for preventing scale unevenness due to abnormal oxidation is disclosed.
　特許文献３には、浸炭性ガス雰囲気で使用されるステンレス鋼として、Ｃｒを２０～５５質量％含有する母材の表面にＣｒ欠乏層におけるＣｒ濃度が１０％質量以上、または、さらにその外側にＣｒ含有量が５０％質量以上のＣｒ主体の酸化スケール層を有するステンレス鋼に関する発明が開示されている。 In Patent Document 3, as a stainless steel used in a carburizing gas atmosphere, the Cr concentration in a Cr-deficient layer is 10% by mass or more on the surface of a base material containing 20 to 55% by mass of Cr, or further on the outside thereof. An invention relating to stainless steel having a Cr-based oxide scale layer having a Cr content of 50% by mass or more is disclosed.
　特許文献４には、耐コーキング性に優れたエチレン分解炉管の製造方法に関して、１５～３０質量％のＣｒと１５～５０質量％のＮｉとを含有する管に、表面から少なくとも５０μｍ深さの冷間加工を施し、次いでその管を酸素５ｖｏｌ％未満で且つ窒素が２０ｖｏｌ％以上の雰囲気中で１１００℃以上に加熱する発明が開示されている。 Patent Document 4 relates to a method for producing an ethylene cracking furnace tube excellent in coking resistance, in a tube containing 15 to 30% by mass of Cr and 15 to 50% by mass of Ni having a depth of at least 50 μm from the surface. An invention is disclosed in which a cold working is performed, and then the tube is heated to 1100 ° C. or higher in an atmosphere of less than 5 vol% oxygen and 20 vol% nitrogen.
特開平２－４７２４９号公報Japanese Patent Laid-Open No. 2-47249 特開平３－１９７６１７号公報Japanese Patent Laid-Open No. 3-197617 特開２００５－４８２８４号公報Japanese Patent Laying-Open No. 2005-48284 特開平２－２６３８９５号公報JP-A-2-263895
　特許文献１および２に記載の発明は、Ｃｒ含有量が２０質量％以下と少ないため、Ｃｒ主体の酸化スケール層を形成することは困難である。 In the inventions described in Patent Documents 1 and 2, since the Cr content is as small as 20% by mass or less, it is difficult to form a Cr-based oxide scale layer.
　特許文献３に記載されるような酸化スケール層を有するステンレス鋼は、耐浸炭性および耐コーキング性に優れる。しかし、実際の製造において管内面全域にわたり均一にＣｒ主体の酸化スケール層を形成することは難しい。 Stainless steel having an oxide scale layer as described in Patent Document 3 is excellent in carburization resistance and caulking resistance. However, in actual production, it is difficult to uniformly form a Cr-based oxide scale layer over the entire inner surface of the tube.
　特許文献４に記載の発明では、冷間加工および窒素浸透熱処理によって、表層から少なくとも３０μｍまでの深さのオーステナイト結晶粒度をＮｏ．７以上の細粒化層とし、７５０～１１００℃の実操業条件下で使用中に生成するＣｒ２Ｏ３酸化皮膜の安定性を向上させることができるとしている。この方法では、窒素浸透熱処理で生成した酸化スケールは除去され、実操業において細粒化層の上に安定なＣｒ２Ｏ３の酸化皮膜が形成される。しかし、実操業中の酸化皮膜の形成には長時間を要する。従って、この方法では、安定した酸化皮膜が形成する前に浸炭またはコーキングが発生するおそれがある。 In the invention described in Patent Document 4, the austenite grain size having a depth of at least 30 μm from the surface layer is set to No. by cold working and nitrogen infiltration heat treatment. 7 or more finely divided layers can improve the stability of the Cr 2 O 3 oxide film produced during use under actual operating conditions of 750 to 1100 ° C. In this method, the oxide scale generated by the nitrogen infiltration heat treatment is removed, and a stable Cr 2 O 3 oxide film is formed on the finely divided layer in actual operation. However, it takes a long time to form an oxide film during actual operation. Therefore, in this method, carburization or coking may occur before a stable oxide film is formed.
　本発明は、このような従来技術の問題点を解決するためになされたものであり、金属管内面に均一なＣｒ主体の酸化スケール層を形成させることにより、浸炭性ガスからの浸炭またはコーキングに対して優れた耐性を有する金属管を製造する方法を提供するを目的としている。 The present invention has been made to solve such problems of the prior art, and by forming a uniform Cr-based oxide scale layer on the inner surface of a metal tube, carburizing or coking from carburizing gas can be achieved. An object of the present invention is to provide a method of manufacturing a metal tube having excellent resistance to the above.
　本発明者らは、金属管内面の全域にわたり、耐浸炭性および耐コーキング性を有するＣｒ主体の酸化スケール層を均一に形成するための方法について鋭意研究を行った結果、不均一スケールが形成される原因とその防止方法について、下記の知見を得た。 As a result of intensive studies on a method for uniformly forming a Cr-based oxide scale layer having carburization resistance and caulking resistance over the entire inner surface of the metal tube, the present inventors have formed a non-uniform scale. The following knowledge was obtained about the cause and the prevention method.
　（Ａ）金属管内面に形成された酸化スケール層について、光学顕微鏡およびＳＥＭ（走査型電子顕微鏡；Ｓｃａｎｎｉｎｇ　Ｅｌｅｃｔｒｏｎ　Ｍｉｃｒｏｓｃｏｐｅ）による観察、ＥＤＸ（エネルギー分散型Ｘ線分光；Ｅｎｅｒｇｙ　Ｄｉｓｐｅｒｓｉｖｅ　Ｘ－ｒａｙ　ｓｐｅｃｔｒｏｍｅｔｒｙ）による元素の定量分析など、様々な検討を行った。その結果、不均一なスケールの表面には、アルカリ金属およびアルカリ土類金属の一方または両方が検出された。 (A) About the oxide scale layer formed on the inner surface of the metal tube, observation by an optical microscope and SEM (scanning electron microscope; Scanning Electron Microscope), element by EDX (energy dispersive X-ray spectroscopy; Energy Dispersive X-ray spectroscopy) Various studies such as quantitative analysis were conducted. As a result, one or both of alkali metal and alkaline earth metal were detected on the surface of the non-uniform scale.
　（Ｂ）本発明者らの検討結果により、これら元素が冷間加工時の潤滑剤に由来するものであり、金属管表面に残存した潤滑剤がＣｒ主体の酸化スケール層の形成を阻害する要因であることが判明した。 (B) According to the results of the study by the present inventors, these elements are derived from a lubricant during cold working, and the lubricant remaining on the surface of the metal tube is a factor that inhibits the formation of a Cr-based oxide scale layer. It turned out to be.
　（Ｃ）冷間加工後に脱脂、洗浄などを行い、管内面に付着した潤滑剤を除去することを試みた。しかし、これらの方法では金属管全長にわたり、潤滑剤を十分に除去できない場合があった。そこで、潤滑剤を除去する方法を種々試験した。その結果、金属管内面にブラスト等の機械的処理を実施することによって、金属管全長にわたり、その内面の潤滑剤を均一に除去し得ることが分かった。 (C) After cold working, degreasing and washing were performed to try to remove the lubricant adhering to the inner surface of the pipe. However, in these methods, the lubricant may not be sufficiently removed over the entire length of the metal tube. Therefore, various methods for removing the lubricant were tested. As a result, it was found that by performing mechanical treatment such as blasting on the inner surface of the metal tube, the lubricant on the inner surface can be uniformly removed over the entire length of the metal tube.
　本発明は、このような知見に基づいてなされたものであり、下記の（１）～（４）に示す金属管の製造方法を要旨とする。 The present invention has been made on the basis of such knowledge, and the gist thereof is a method for producing a metal tube as shown in the following (1) to (4).
　（１）質量％で、２０～５５％のＣｒおよび２０～７０％のＮｉを含有する金属管の内表面に機械的処理を実施した後、
１０５０～１２７０℃の温度範囲で、０．５～６０分保持する熱処理を実施して、
金属管の少なくとも内表面にＣｒ主体の酸化スケール層を形成する
金属管の製造方法。 (1) After performing mechanical treatment on the inner surface of a metal tube containing 20 to 55% Cr and 20 to 70% Ni by mass%,
In the temperature range of 1050 to 1270 ° C., heat treatment is performed for 0.5 to 60 minutes,
A method of manufacturing a metal tube, comprising forming a Cr-based oxide scale layer on at least the inner surface of the metal tube.
　（２）前記金属管が、質量％で、Ｃ：０．０１～０．６％、Ｓｉ：０．１～５％、Ｍｎ：０．１～１０％、Ｐ：０．０８％以下、Ｓ：０．０５％以下、Ｃｒ：２０～５５％、Ｎｉ：２０～７０％、Ｎ：０．００１～０．２５％およびＯ（酸素）：０．０２％以下を含有し、
残部がＦｅおよび不純物からなる化学組成を有する
上記（１）の金属管の製造方法。 (2) The metal tube is, by mass%, C: 0.01 to 0.6%, Si: 0.1 to 5%, Mn: 0.1 to 10%, P: 0.08% or less, S : 0.05% or less, Cr: 20 to 55%, Ni: 20 to 70%, N: 0.001 to 0.25% and O (oxygen): 0.02% or less,
The method for producing a metal tube according to the above (1), wherein the balance has a chemical composition comprising Fe and impurities.
　（３）前記金属管が、質量％で、更に、下記（ａ）～（ｇ）に掲げる元素から選択される１種以上を含有する
上記（２）の金属管の製造方法。
（ａ）　Ｃｕ：５％以下、
（ｂ）　Ｃｏ：５％以下、
（ｃ）　Ｍｏ：３％以下、Ｗ：６％以下およびＴａ：６％以下から選択される１種以上、
（ｄ）　Ｔｉ：１％以下およびＮｂ：２％以下から選択される１種または２種、
（ｅ）　Ｂ：０．１％以下、Ｚｒ：０．１％以下およびＨｆ：０．５％以下から選択される１種以上、
（ｆ）　Ｍｇ：０．１％以下、Ｃａ：０．１％以下およびＡｌ：１％以下から選択される１種以上、
（ｇ）　Ｙ：０．１５％以下およびＬｎ族：０．１５％以下から選択される１種以上。 (3) The method for producing a metal tube according to (2), wherein the metal tube further contains at least one element selected from the elements listed in the following (a) to (g) by mass%.
(A) Cu: 5% or less,
(B) Co: 5% or less,
(C) one or more selected from Mo: 3% or less, W: 6% or less, and Ta: 6% or less,
(D) Ti: 1% or less and Nb: 1 or 2 types selected from 2% or less,
(E) one or more selected from B: 0.1% or less, Zr: 0.1% or less, and Hf: 0.5% or less,
(F) one or more selected from Mg: 0.1% or less, Ca: 0.1% or less, and Al: 1% or less,
(G) One or more selected from Y: 0.15% or less and Ln group: 0.15% or less.
　（４）前記金属管が、管内面にリブ状の突起を有する
上記（１）～（３）のいずれかの金属管の製造方法。 (4) The method for producing a metal tube according to any one of (1) to (3), wherein the metal tube has a rib-like protrusion on the inner surface of the tube.
　本発明によれば、金属管内表面に均一にＣｒ主体の酸化スケール層を備える金属管を製造することができる。本発明の製造方法によって得られた金属管は、浸炭性ガス環境における耐浸炭性および耐コーキング性に優れる。 According to the present invention, it is possible to manufacture a metal tube having a Cr-based oxide scale layer uniformly on the inner surface of the metal tube. The metal pipe obtained by the production method of the present invention is excellent in carburization resistance and coking resistance in a carburizing gas environment.
　この発明は、所定の化学組成を有する金属管の内表面に機械的処理を実施した後、１０５０～１２７０℃の温度範囲で、０．５～６０分保持する熱処理を実施することにより、金属管の少なくとも内表面にＣｒ主体の酸化スケール層を形成するものである。以下、本発明の製造方法に供される金属管の化学組成、ならびに、金属管に施される機械的処理および熱処理について説明する。以下の説明において、各元素の含有量の「％」表示は「質量％」を意味する。 According to the present invention, a metal tube having a predetermined chemical composition is mechanically treated and then subjected to a heat treatment for 0.5 to 60 minutes in a temperature range of 1050 to 1270 ° C. A Cr-based oxide scale layer is formed on at least the inner surface of the film. Hereinafter, the chemical composition of the metal tube used in the production method of the present invention, and the mechanical treatment and heat treatment applied to the metal tube will be described. In the following description, “%” display of the content of each element means “mass%”.
　１．金属管の化学組成
　この発明の製造方法に供される金属管は、２０～５５％のＣｒおよび２０～７０％のＮｉを含有することが必要である。 1. Chemical composition of metal tube The metal tube used for the production method of the present invention needs to contain 20 to 55% Cr and 20 to 70% Ni.
　Ｃｒ：２０～５５％
　Ｃｒは、２０％以上含有させることが必要である。これは、金属管の少なくとも内面にＣｒ主体の酸化スケ－ルを安定に形成するためである。しかしながら、過剰に含有させると、金属管の製造を困難にさせると共に、高温での使用中に組織が不安定になるおそれがあるので、上限は５５％とする。加工性の確保および組織安定性の劣化防止のためには、上限は３５％とすることが好ましい。より好ましい範囲は、２２～３３％である。 Cr: 20-55%
It is necessary to contain 20% or more of Cr. This is to stably form a Cr-based oxide scale on at least the inner surface of the metal tube. However, if it is contained excessively, the manufacture of the metal tube becomes difficult, and the structure may become unstable during use at a high temperature, so the upper limit is made 55%. In order to ensure processability and prevent deterioration of the structure stability, the upper limit is preferably 35%. A more preferred range is 22 to 33%.
　Ｎｉ：２０～７０％
　Ｎｉは、安定したオーステナイト組織を得るために必要な元素である。Ｎｉは、Ｃｒ含有量に応じて適量含有させる。Ｎｉは、炭素の金属材料中への侵入速度を低減する働きがある。これらの効果は、その含有量が２０％以上の場合に発揮される。しかしながら、これらの効果は、Ｎｉを過剰に添加しても飽和するので、製造コストを上昇させる。過剰なＮｉは、管の製造を困難にさせる。従って、Ｎｉ含有量は２０～７０％とした。好ましい下限は２３％であり、好ましい上限は６０％である。より好ましい上限は５０％である。 Ni: 20-70%
Ni is an element necessary for obtaining a stable austenite structure. Ni is contained in an appropriate amount according to the Cr content. Ni has a function of reducing the penetration rate of carbon into the metal material. These effects are exhibited when the content is 20% or more. However, these effects saturate even when Ni is added excessively, thus increasing the manufacturing cost. Excessive Ni makes tube manufacture difficult. Therefore, the Ni content is 20 to 70%. A preferred lower limit is 23% and a preferred upper limit is 60%. A more preferred upper limit is 50%.
　エチレン製造用金属管（エチレンクラッキングチューブ）の素材としては、Ｃｒ：２０～３５％およびＮｉ：２０～６０％を含むものが好ましい。 The material for the metal tube for ethylene production (ethylene cracking tube) preferably contains Cr: 20 to 35% and Ni: 20 to 60%.
　本発明の製造方法に供される金属管は、上記の化学組成を有し、他の成分については特に制約はないが、例えば、Ｃ：０．０１～０．６％、Ｓｉ：０．１～５％、Ｍｎ：０．１～１０％、Ｐ：０．０８％以下、Ｓ：０．０５％以下、Ｃｒ：２０～５５％、Ｎｉ：２０～７０％、Ｎ：０．００１～０．２５％およびＯ（酸素）：０．０２％以下を含有し、残部がＦｅおよび不純物からなる化学組成を有するものが好ましい。以下、各元素の限定理由を述べる。 The metal tube used in the production method of the present invention has the above-described chemical composition, and there are no particular restrictions on the other components. For example, C: 0.01 to 0.6%, Si: 0.1 -5%, Mn: 0.1-10%, P: 0.08% or less, S: 0.05% or less, Cr: 20-55%, Ni: 20-70%, N: 0.001-0 .25% and O (oxygen): 0.02% or less is preferable, and the remainder has a chemical composition composed of Fe and impurities. The reasons for limiting each element are described below.
　不純物とは、金属管を工業的に製造する際に、鉱石、スクラップ等から混入する成分であって、本発明に悪影響を与えない範囲で許容されるものを意味する。 Impurity means a component mixed from ore, scrap and the like when industrially producing a metal tube, and is allowed within a range that does not adversely affect the present invention.
　Ｃ：０．０１～０．６％
　Ｃは、高温強度を確保するのに有効な元素である。この効果は、Ｃを０．０１％以上含有させた場合に顕著となる。一方、その含有量が０．６％を超えると、靭性が極端に悪くなるおそれがある。従って、Ｃの含有量は０．０１～０．６％とするのが好ましい。より好ましい下限は０．０２％である。より好ましい上限は０．４５％である。さらに好ましい上限は０．３％である。 C: 0.01 to 0.6%
C is an element effective for ensuring high temperature strength. This effect becomes remarkable when C is contained by 0.01% or more. On the other hand, when the content exceeds 0.6%, the toughness may be extremely deteriorated. Therefore, the C content is preferably 0.01 to 0.6%. A more preferred lower limit is 0.02%. A more preferred upper limit is 0.45%. A more preferred upper limit is 0.3%.
　Ｓｉ：０．１～５％
　Ｓｉは、酸素との親和力が強いため、Ｃｒ主体の酸化スケ－ル層の均一形成を助長する効果を有する。この効果は、０．１％以上含有させた場合に顕著となる。ただし、その含有量が５％を超えると、溶接性が劣化し、組織も不安定になるおそれがある。従って、Ｓｉの含有量は０．１～５％とするのが好ましい。好ましい上限は３％であり、より好ましい上限は２％である。また、より好ましい下限は０．３％である。 Si: 0.1 to 5%
Since Si has a strong affinity for oxygen, it has the effect of promoting uniform formation of a Cr-based oxide scale layer. This effect becomes significant when the content is 0.1% or more. However, if its content exceeds 5%, the weldability deteriorates and the structure may become unstable. Accordingly, the Si content is preferably 0.1 to 5%. A preferable upper limit is 3%, and a more preferable upper limit is 2%. A more preferred lower limit is 0.3%.
　Ｍｎ：０．１～１０％
　Ｍｎは、脱酸に有効であるとともに、加工性の改善に有効な元素である。また、Ｍｎは、オーステナイト生成元素であることからＮｉの一部をＭｎに置換できる。これらの効果を得るためには、０．１％以上含有させることが好ましい。しかし、過剰に含有させると、Ｃｒ主体の酸化スケール層の形成を阻害するおそれがある。従って、Ｍｎの含有量は０．１～１０％とするのが好ましい。好ましい上限は５％であり、より好ましい上限は２％である。 Mn: 0.1 to 10%
Mn is an element effective for deoxidation and effective for improving workability. Further, since Mn is an austenite generating element, a part of Ni can be replaced with Mn. In order to acquire these effects, it is preferable to make it contain 0.1% or more. However, if excessively contained, the formation of a Cr-based oxide scale layer may be hindered. Accordingly, the Mn content is preferably 0.1 to 10%. A preferable upper limit is 5%, and a more preferable upper limit is 2%.
Ｐ：０．０８％以下、
Ｓ：０．０５％以下
　ＰおよびＳは、結晶粒界に偏析し、熱間加工性を劣化させるため、極力低減することが好ましい。ただし、過剰な低減はコスト高を招くため、Ｐは０．０８％以下、Ｓは０．０５％以下とするのが好ましい。より好ましいのは、Ｐは０．０５％以下、Ｓは０．０３％以下である。さらに好ましいのは、Ｐは０．０４％以下、Ｓは０．０１５％以下である。 P: 0.08% or less,
S: 0.05% or less P and S are preferably segregated at the crystal grain boundaries and deteriorated in hot workability. However, excessive reduction leads to high costs, so it is preferable that P is 0.08% or less and S is 0.05% or less. More preferably, P is 0.05% or less and S is 0.03% or less. More preferably, P is 0.04% or less, and S is 0.015% or less.
　Ｎ：０．００１～０．２５％
　Ｎは、高温強度改善に有効な元素である。この効果が顕著となるのは、０．００１％以上含有させた場合である。しかし、過剰な添加は、加工性を大きく阻害するおそれがある。従って、Ｎの含有量は、０．００１～０．２５％とするのが好ましい。好ましい上限は、０．２％である。 N: 0.001 to 0.25%
N is an element effective for improving the high-temperature strength. This effect becomes remarkable when the content is 0.001% or more. However, excessive addition may greatly impair processability. Therefore, the N content is preferably 0.001 to 0.25%. A preferable upper limit is 0.2%.
　Ｏ（酸素）：０．０２％以下
　酸素（Ｏ）は不純物として存在する元素である。酸素含有量が０．０２％を超えると、金属材料中に酸化物系介在物が多量に析出し、加工性を低下させ、管の表面疵の原因になる。従って、酸素の含有量は０．０２％以下とするのが好ましい。
O (oxygen): 0.02% or less Oxygen (O) is an element present as an impurity. When the oxygen content exceeds 0.02%, a large amount of oxide inclusions are precipitated in the metal material, the workability is lowered, and the surface flaw of the tube is caused. Therefore, the oxygen content is preferably 0.02% or less.
　上記の金属管には、更に、下記（ａ）～（ｇ）に掲げる元素から選択される１種を含有させてもよい。 The metal tube may further contain one type selected from the elements listed in the following (a) to (g).
　（ａ）Ｃｕ：５％以下
　Ｃｕは、オーステナイト相を安定にする元素である。Ｃｕは、高温強度を向上させるのに有効な元素でもある。よって、Ｃｕを上記の金属管に含有させても良い。しかし、その含有量が過剰な場合には熱間加工性を低下させるおそれがある。よって、Ｃｕを含有させる場合にはその含有量を５％以下とするのが好ましい。より好ましい上限は３％である。上記の効果は、０．１％以上含有させた場合に顕著となる。 (A) Cu: 5% or less Cu is an element that stabilizes the austenite phase. Cu is also an element effective for improving the high-temperature strength. Therefore, Cu may be contained in the metal tube. However, when the content is excessive, hot workability may be reduced. Therefore, when Cu is contained, the content is preferably 5% or less. A more preferred upper limit is 3%. Said effect becomes remarkable when it contains 0.1% or more.
　（ｂ）Ｃｏ：５％以下
　Ｃｏは、オーステナイト相を安定にする元素である。Ｃｏを含有させればＮｉの一部と置換することができる。よって、Ｃｏを上記の金属管に含有させても良い。しかし、その含有量が過剰な場合には熱間加工性を低下させるおそれがある。よって、Ｃｏを含有させる場合にはその含有量を５％以下とするのが好ましい。より好ましい上限は３％である。上記の効果は、０．１％以上含有させた場合に顕著となる。 (B) Co: 5% or less Co is an element that stabilizes the austenite phase. If Co is contained, a part of Ni can be substituted. Therefore, Co may be contained in the metal tube. However, when the content is excessive, hot workability may be reduced. Therefore, when Co is contained, the content is preferably 5% or less. A more preferred upper limit is 3%. Said effect becomes remarkable when it contains 0.1% or more.
　（ｃ）　Ｍｏ：３％以下、Ｗ：６％以下およびＴａ：６％以下から選択される１種以上
　Ｍｏ、ＷおよびＴａは、いずれも固溶強化に寄与する元素であり、高温強度向上に有効である。よって、これらの元素から選択される一種以上を上記の金属管に含有させても良い。しかし、その含有量が過剰な場合には加工性を劣化させるとともに、組織安定性を阻害するおそれがある。従って、これらの元素の１種以上を含有させる場合、Ｍｏは３％、ＷおよびＴａは６％以下にするのが好ましい。これらの元素の好ましい上限は、いずれも２．５％である。さらに好ましい上限は２％である。なお、いずれの元素においても上記の効果は０．０１％以上含有させた場合に顕著となる。また、これらを複合して含有させる場合は、その合計量の上限を１０％とするのが好ましい。 (C) One or more selected from Mo: 3% or less, W: 6% or less, and Ta: 6% or less Mo, W, and Ta are all elements that contribute to solid solution strengthening and improve high-temperature strength. It is valid. Therefore, one or more selected from these elements may be contained in the metal tube. However, when the content is excessive, the workability is deteriorated and the tissue stability may be impaired. Therefore, when one or more of these elements are contained, Mo is preferably 3% and W and Ta are preferably 6% or less. A preferable upper limit of these elements is 2.5%. A more preferred upper limit is 2%. In any element, the above effect becomes remarkable when 0.01% or more is contained. Moreover, when these are compounded and contained, it is preferable to make the upper limit of the total amount into 10%.
　（ｄ）　Ｔｉ：１％以下およびＮｂ：２％以下から選択される１種または２種
　ＴｉおよびＮｂは、極微量の含有でも高温強度、延性および靱性の改善に大きな効果がある。よって、これらの元素から選択される一種または二種を上記の金属管に含有させても良い。しかし、これらの元素を過剰に含有させると、加工性および溶接性を低下させるおそれがある。従って、これらの元素の１種または２種を含有させる場合、Ｔｉは１％以下、Ｎｂは２％以下とするのが好ましい。なお、いずれの元素においても上記の効果は０．０１％以上含有させた場合に顕著となる。また、これらを複合して含有させる場合は、その合計量の上限を２％とするのが好ましい。 (D) Ti: 1% or less and Nb: 1 or 2 selected from 2% or less Ti and Nb have a great effect in improving high-temperature strength, ductility and toughness even if contained in a very small amount. Therefore, one or two selected from these elements may be contained in the metal tube. However, when these elements are contained excessively, workability and weldability may be deteriorated. Therefore, when one or two of these elements are contained, Ti is preferably 1% or less and Nb is preferably 2% or less. In any element, the above effect becomes remarkable when 0.01% or more is contained. Moreover, when these are compounded and contained, it is preferable to make the upper limit of the total amount into 2%.
　（ｅ）　Ｂ：０．１％以下、Ｚｒ：０．１％以下およびＨｆ：０．５％以下から選択される１種以上
　Ｂ、ＺｒおよびＨｆは、いずれも粒界を強化し、熱間加工性および高温強度特性を改善するのに有効な元素であるよって、これらの元素から選択される１種以上を上記の金属管に含有させても良い。しかし、いずれの元素もその含有量が過剰な場合には溶接性を劣化させるおそれがある。従って、これらの元素の１種以上を含有させる場合、ＢおよびＺｒの含有量は０．１％以下、Ｈｆの含有量は０．５％以下とするのが好ましい。なお、いずれの元素においても上記の効果は０．００１％以上含有させた場合に顕著となる。また、これらを複合して含有させる場合は、その合計量の上限を０．３％とするのが好ましい。 (E) One or more selected from B: 0.1% or less, Zr: 0.1% or less, and Hf: 0.5% or less B, Zr, and Hf all strengthen grain boundaries and are hot Since it is an effective element for improving workability and high-temperature strength characteristics, one or more selected from these elements may be contained in the metal tube. However, if the content of any element is excessive, the weldability may be deteriorated. Therefore, when one or more of these elements are contained, the B and Zr contents are preferably 0.1% or less, and the Hf content is preferably 0.5% or less. In any element, the above effect becomes remarkable when 0.001% or more is contained. Moreover, when these are compounded and contained, it is preferable to make the upper limit of the total amount into 0.3%.
　（ｆ）　Ｍｇ：０．１％以下、Ｃａ：０．１％以下およびＡｌ：１％以下から選択される１種以上
　Ｍｇ、ＣａおよびＡｌは、いずれも熱間加工性を改善するのに有効な元素である。よって、これらの元素から選択される１種以上を上記の金属管に含有させても良い。しかし、これらの元素の含有量が過剰な場合には、溶接性を劣化させるおそれがある。従って、これらの元素の１種以上を含有させる場合、Ｍｇの含有量は０．１％以下、Ｃａの含有量は０．１％以下、Ａｌの含有量１％以下とするのが好ましい。より好ましい上限は、ＭｇおよびＣａでは０．０５％、Ａｌでは０．６％である。なお、上記の効果は、ＭｇおよびＣａでは０．００１％以上、Ａｌでは０．０１％以上含有させた場合に顕著となる。より好ましい下限は、ＭｇおよびＣａでは０．００２％である。また、これらを複合して含有させる場合は、その合計量の上限を０．５％とするのが好ましい。 (F) One or more selected from Mg: 0.1% or less, Ca: 0.1% or less, and Al: 1% or less Mg, Ca, and Al are all effective in improving hot workability Element. Therefore, you may make 1 or more types selected from these elements contain in said metal pipe. However, when the content of these elements is excessive, the weldability may be deteriorated. Therefore, when one or more of these elements are contained, the Mg content is preferably 0.1% or less, the Ca content is 0.1% or less, and the Al content is 1% or less. A more preferable upper limit is 0.05% for Mg and Ca, and 0.6% for Al. In addition, said effect becomes remarkable when it contains 0.001% or more in Mg and Ca, and 0.01% or more in Al. A more preferred lower limit is 0.002% for Mg and Ca. Moreover, when these are compounded and contained, it is preferable to make the upper limit of the total amount into 0.5%.
　（ｇ）　Ｙ：０．１５％以下およびＬｎ族：０．１５％以下から選択される１種以上
　ＹおよびＬｎ族は、耐酸化性の向上に有効な元素である。よって、これらの元素から選択される１種以上を上記の金属管に含有させても良い。いずれの元素もその含有量が過剰な場合、加工性を低下させる。従って、これらの元素の１種以上を含有させる場合には、いずれもその含有量を０．１５％以下とするのが好ましい。なお、上記の効果は、いずれの元素においても０．０００５％以上含有させた場合に顕著となる。好ましい含有量の上限はいずれも０．１０％以下である。また、これらを複合して含有させる場合は、その合計量の上限を０．１５％とするのが好ましい。Ｌｎ族とは、元素番号５７のＬａから同７１のＬｕまでを指す。Ｌｎ族の中でも、特にＬａ、ＣｅおよびＮｄの１種以上を用いることが好ましい。 (G) One or more selected from Y: 0.15% or less and Ln group: 0.15% or less Y and Ln group are effective elements for improving oxidation resistance. Therefore, you may make 1 or more types selected from these elements contain in said metal pipe. When the content of any element is excessive, workability is reduced. Therefore, when one or more of these elements are contained, the content is preferably 0.15% or less. In addition, said effect becomes remarkable when it contains 0.0005% or more in any element. The upper limit of the preferable content is 0.10% or less. Moreover, when these are compounded and contained, it is preferable to make the upper limit of the total amount into 0.15%. The Ln group means from La of element number 57 to Lu of element 71. Among Ln groups, it is particularly preferable to use one or more of La, Ce and Nd.
　２．機械的処理
　金属管を加工する場合に、金属管と加工工具との摩擦を低減するために潤滑剤が使用される。潤滑剤は、通常、加工後に脱脂および洗浄を行うことで除去される。、しかし、潤滑剤の一部は管内面に残存する。前述のように、金属管表面に残存した潤滑剤がＣｒ主体の酸化スケール層の形成を阻害するので、本発明では、これを除去するために機械的処理を行う。金属管表面には上記潤滑剤の他、熱間製管時に生成した酸化スケール、汚れ等が付着残存する場合がある。これらの残存物は、Ｃｒ主体の酸化スケール層の均一形成を阻害するので、除去することが望ましい。 2. Mechanical processing When processing a metal tube, a lubricant is used to reduce the friction between the metal tube and the processing tool. The lubricant is usually removed by degreasing and washing after processing. However, a part of the lubricant remains on the inner surface of the pipe. As described above, since the lubricant remaining on the surface of the metal tube inhibits the formation of the oxide scale layer mainly composed of Cr, in the present invention, a mechanical treatment is performed to remove this. In addition to the above-mentioned lubricant, oxidized scale, dirt, etc. generated during hot pipe production may adhere and remain on the surface of the metal pipe. These residues are preferably removed because they inhibit the uniform formation of the Cr-based oxide scale layer.
　ここで、機械的処理とは、金属管の表面に残存した潤滑剤、汚れ、酸化スケールなどの付着物を物理的に除去することにより表面清浄度を高める処理である。機械的処理としては、例えば、ブラスト処理、研磨材を直接金属管内面に接触させ、擦ることで除去する研削処理（または摩擦処理）、研磨材なしに高圧水を吹き付けて除去する方法などが挙げられる。ブラスト処理には、例えば、圧縮空気により投射材を投射するエアーブラスト、砂を投射材に用いたサンドブラスト（エアーブラストの一種）、耐磨耗合金製の羽根車の遠心力により投射材を投射するショットブラスト、金属表面にひずみを付与することを主たる目的とするショットピーニング（ショットブラストの一種）、湿式ブラストなどがある。ショットピーニングは、ひずみ付与と同時に表面付着物の除去が可能である。また、投射材を高圧水とともに投射する湿式ブラストも適用できる。 Here, the mechanical treatment is a treatment for enhancing the surface cleanliness by physically removing deposits such as lubricant, dirt and oxide scale remaining on the surface of the metal tube. Examples of the mechanical treatment include a blasting treatment, a grinding treatment (or friction treatment) in which an abrasive is directly brought into contact with the inner surface of the metal tube and removed by rubbing, and a method in which high pressure water is sprayed and removed without the abrasive. It is done. In the blast treatment, for example, air blast for projecting a projection material with compressed air, sand blasting using sand as a projection material (a type of air blasting), and projection material is projected by centrifugal force of an impeller made of wear-resistant alloy. There are shot blasting, shot peening (a kind of shot blasting) whose main purpose is to impart strain to the metal surface, wet blasting and the like. Shot peening can remove surface deposits at the same time as applying strain. In addition, wet blasting in which the projection material is projected with high-pressure water can also be applied.
　機械的処理に用いる研磨材には、特に制限はないが、たとえば、珪砂（ＳｉＯ２）、アルミナ（Ａｌ２Ｏ３）、ジルコニア（ＺｒＯ２）、窒化ホウ素（ＢＮ）、炭化けい素（ＳｉＣ）などの非金属、これらの混合物、または、これらを主成分とする研磨材が好適である。また、鋳鋼、ステンレス鋼、金属ガラス（アモルファス）、Ｃｒなどの金属からなる研磨材を用いても良い。研磨材を固着させた不織布等を用いてもよい。研磨材の形状にも特に制限はなく、粒状、グリット状、粉状など、いずれの形態でも良い。研磨材の大きさにも特に制限はない。ただし、耐コーキング性を高めるために表面粗度を抑制する場合には、平均粒径（長径と短径の平均）として３００μｍ以下が好ましく、１５０μｍ以下がもっとも好ましい。 The abrasive used for the mechanical treatment is not particularly limited. For example, silica sand (SiO 2 ), alumina (Al 2 O 3 ), zirconia (ZrO 2 ), boron nitride (BN), silicon carbide (SiC) Nonmetals such as these, mixtures thereof, or abrasives based on these are preferred. Moreover, you may use the abrasives which consist of metals, such as cast steel, stainless steel, metal glass (amorphous), and Cr. You may use the nonwoven fabric etc. which fixed the abrasives. There is no restriction | limiting in particular also in the shape of an abrasives, Any form, such as granular form, a grit form, and a powder form, may be sufficient. There is no particular limitation on the size of the abrasive. However, when the surface roughness is suppressed in order to improve the coking resistance, the average particle diameter (average of the major axis and the minor axis) is preferably 300 μm or less, and most preferably 150 μm or less.
　上記研磨材を高速で管内面に吹き付ける場合は、金属管の片端または両端から吹き付けてもよいし、金属管内に吹き付けノズルを挿入し、管内を移動しながら吹き付けてもよい。研磨材もしくは研磨材を固着させた不織布を乾いたまま、または液体に湿らせて直接金属管内面に接触させ、擦りながら移動させてもよい。 When spraying the abrasive on the inner surface of the pipe at high speed, it may be sprayed from one end or both ends of the metal pipe, or may be sprayed by inserting a spray nozzle into the metal pipe and moving in the pipe. The abrasive or the non-woven fabric to which the abrasive is fixed may be dried or wetted with a liquid to directly contact the inner surface of the metal tube and move while rubbing.
　３．熱処理
　機械的処理を施した金属管は、熱処理が施され、金属管内面にＣｒ主体の酸化スケール層が形成される。熱処理温度が１０５０℃未満では、金属管表面に形成される酸化スケール層が薄く、炭素の金属材料中侵入に対する遮蔽特性が十分でない。一方、１２７０℃を超えると、酸化スケール層に気孔や割れが生じ、緻密度が低下する結果、耐浸炭性が低下する。従って、熱処理は、１０５０～１２７０℃の温度範囲で行うこととした。好ましい下限は１１２０℃であり、さらに好ましいのは１１６０℃である。 3. Heat treatment The metal tube subjected to the mechanical treatment is subjected to heat treatment, and a Cr-based oxide scale layer is formed on the inner surface of the metal tube. When the heat treatment temperature is less than 1050 ° C., the oxide scale layer formed on the surface of the metal tube is thin, and the shielding property against penetration of carbon into the metal material is not sufficient. On the other hand, when the temperature exceeds 1270 ° C., pores and cracks are generated in the oxide scale layer, and as a result, the density decreases, and the carburization resistance decreases. Therefore, the heat treatment was performed in the temperature range of 1050 to 1270 ° C. A preferred lower limit is 1120 ° C, and more preferred is 1160 ° C.
　上記熱処理の保持時間が０．５分未満では、耐浸炭性に優れたＣｒ主体の酸化スケール層が均一に形成できない。一方、保持時間が６０分を超えても、酸化スケール層の厚さが厚くなるだけで、生産性の低下、エネルギーコストが嵩む。しかも、酸化スケール層の緻密度が低下するという問題もある。そのため、上記温度範囲での保持期間は、０．５～６０分とした。好ましい下限は２分であり、より好ましいのは５分である。また、好ましい上限は３０分であり、より好ましいのは１５分である。 If the holding time of the heat treatment is less than 0.5 minutes, a Cr-based oxide scale layer having excellent carburization resistance cannot be formed uniformly. On the other hand, even if the holding time exceeds 60 minutes, only the thickness of the oxide scale layer is increased, resulting in a decrease in productivity and an increase in energy cost. Moreover, there is a problem that the density of the oxide scale layer is lowered. Therefore, the holding period in the above temperature range is set to 0.5 to 60 minutes. The preferred lower limit is 2 minutes, and more preferred is 5 minutes. The preferred upper limit is 30 minutes, and more preferred is 15 minutes.
　なお、機械的処理後に脱脂、洗浄、酸洗処理などを積極的に行うことが好ましい。これらの処理を施した後に熱処理を行っても、Ｃｒ主体の酸化スケール層の均一形成を阻害しない。これらの処理は、研磨材が管内面に残留することによる清浄度の低下を懸念する場合に特に有効である。熱処理におけるガス雰囲気は、Ｃｒ主体の酸化スケール層を形成し得る条件であればよい。たとえば、大気ガス、炭化水素燃料（ＬＮＧ、ブタンなど）と空気とを燃焼させたガスなどの雰囲気である。また、ＤＸガス、ＮＸガス、ＲＸガス、ＣＯＧ（Ｃガス）、露点を制御した水素ガスなどの雰囲気でもよい。これらのガスを任意の割合で混合させたガスの雰囲気でもよい。 In addition, it is preferable to positively perform degreasing, washing, pickling treatment, etc. after the mechanical treatment. Even if heat treatment is performed after these treatments, the uniform formation of the Cr-based oxide scale layer is not hindered. These treatments are particularly effective when there is concern about a decrease in cleanliness due to the abrasive remaining on the pipe inner surface. The gas atmosphere in the heat treatment may be any conditions that can form a Cr-based oxide scale layer. For example, it is an atmosphere such as atmospheric gas, a gas obtained by burning hydrocarbon fuel (LNG, butane, etc.) and air. Further, the atmosphere may be DX gas, NX gas, RX gas, COG (C gas), hydrogen gas with a controlled dew point, or the like. A gas atmosphere in which these gases are mixed at an arbitrary ratio may be used.
　４．Ｃｒ主体の酸化スケール層
　Ｃｒ主体の酸化スケ－ル層は、耐浸炭性および耐コーキング性の観点から、非常に重要である。特に、５０％以上のＣｒを含有する酸化スケール層は、緻密度が高く、炭素の金属材料中侵入に対する遮蔽特性に富む。Ｃｒ主体の酸化スケール層は、コーキングに対し触媒作用が小さいため、金属材料表面へのコーキングを抑制する。その結果、管内流体への熱伝導性を長時間保つ。例えば、分解反応管として用いた場合、オレフィンなどの反応生成物の収率が安定する。 4). Cr-based oxide scale layer The Cr-based oxide scale layer is very important from the viewpoint of carburization resistance and coking resistance. In particular, an oxide scale layer containing 50% or more of Cr has a high density and a high shielding property against penetration of carbon into the metal material. Since the Cr-based oxide scale layer has a small catalytic effect on coking, it suppresses coking on the surface of the metal material. As a result, the thermal conductivity to the fluid in the pipe is maintained for a long time. For example, when used as a decomposition reaction tube, the yield of reaction products such as olefins is stabilized.
　酸化スケ－ル層中のＣｒ含有量は、８０％以上とするのが好ましい。高いＣｒ含有量の酸化スケール層は、より緻密であり、炭素の金属材料中侵入に対して強固な遮蔽果を発揮する。酸化スケール層中の元素含有量は、ＥＤＸで測定できる。測定は、酸化スケール層の表面から分析すればよい。元素の定量は、Ｃ（炭素）、Ｏ（酸素）などを除いた検出元素の分率で求める。 The Cr content in the oxide scale layer is preferably 80% or more. The oxide scale layer having a high Cr content is denser and exhibits a strong shielding effect against the penetration of carbon into the metal material. The element content in the oxide scale layer can be measured by EDX. The measurement may be performed from the surface of the oxide scale layer. The quantification of the element is determined by the fraction of the detection element excluding C (carbon), O (oxygen) and the like.
　５．その他
　本発明は、金属管の内面にリブ状の突起が設けられているものを製造する場合に特に有用である。通常、このような内面にリブ状の突起を備えている金属管の場合、浸炭性ガスによる攻撃を受け易く、酸化スケールの剥離などが起こり易いと考えられている。しかし、本発明によれば、管内面の耐浸炭性が高く、かつ皮膜の修復能が高い金属管を得ることができる。管内面にリブ状の突起を設けた管の例としては、内面突起付き管、ひれ付管などが挙げられる。突起、ひれなどは、管自体と一体形成されていても、溶接などにより形成されていてもよい。 5). Others The present invention is particularly useful when manufacturing a metal tube having rib-like projections on the inner surface. Usually, in the case of such a metal tube having rib-like protrusions on its inner surface, it is considered that it is easily attacked by a carburizing gas, and oxide scale peeling is likely to occur. However, according to the present invention, it is possible to obtain a metal pipe having high carburization resistance on the inner surface of the pipe and high repair ability of the coating. As an example of a tube having a rib-like projection on the inner surface of the tube, a tube with an inner projection, a finned tube, and the like can be given. The protrusions, fins, etc. may be formed integrally with the tube itself or may be formed by welding or the like.
　実施例によってこの発明をより具体的に説明するが、この発明はそれら実施例に限定されるものではない。 The present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
　表１に示す化学組成の金属材料を電気炉もしくは真空溶解炉を用いて溶製し、ビレットを形成した。得られたビレットに熱間鍛造および冷間圧延を行って、外径５６ｍｍ、肉厚６ｍｍの金属管を作製した。供試材番号１～１０の金属管に対し、表２に示す条件の機械的処理を行った。一部のものは機械的処理を省略した。これらに、表２に記載の条件で熱処理を行い、酸化スケールを形成した。一部のものは、機械的処理としてのアルミナブラストを実施し、熱処理を行わなかった。金属管内での均一な耐浸炭性および耐コーキング性を評価する目的で、管長手方向より２ｍピッチで合計５ヶ所を切断して、幅５０ｍｍのリング状試験片と後述する酸化スケール観察用試験片（２０ｘ２０ｍｍ角）を採取した。 A metal material having the chemical composition shown in Table 1 was melted using an electric furnace or a vacuum melting furnace to form a billet. The obtained billet was hot forged and cold rolled to produce a metal tube having an outer diameter of 56 mm and a wall thickness of 6 mm. Mechanical treatment under the conditions shown in Table 2 was performed on the metal tubes of specimen numbers 1 to 10. Some omitted mechanical processing. These were heat-treated under the conditions described in Table 2 to form oxide scales. Some performed alumina blasting as a mechanical treatment and no heat treatment. For the purpose of evaluating uniform carburization resistance and caulking resistance in a metal tube, a total of five locations are cut at a pitch of 2 m from the longitudinal direction of the tube, and a ring-shaped test piece having a width of 50 mm and an oxide scale observation test piece to be described later. (20 × 20 mm square) was collected.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　観察用試験片の表面からＥＤＸ分析を行い、金属管に生成した酸化スケ－ル層中のＣｒ含有量（質量％）を３ヶ所測定の平均から求めた。一方、リング状試験片を、体積比で１５％ＣＨ４－３％ＣＯ２－８２％Ｈ２のガス雰囲気中で、１０００℃にて３００時間保持し、浸炭およびコーキング試験を行った。耐コーキング性は、試験前および試験後の試験片の質量を測定し、、コーク堆積による増加分を求め、単位面積当たりの堆積コーク量（ｍｇ／ｃｍ２）を求めた。一方、耐浸炭性は、母材に侵入するＣ量で評価した。すなわち、試験後の試験片の表面より深さ方向に０．５ｍｍピッチで金属切り粉を採取し、０．５～１．０ｍｍ深さにおけるＣ量（質量％）と１．０～１．５ｍｍ深さにおけるＣ量（質量％）を化学分析により測定し、試験前の母材Ｃ量（質量％）を減じた後、両Ｃ量の平均値を１ｍｍ深さにおける侵入Ｃ量（質量％）とした。 EDX analysis was performed from the surface of the observation specimen, and the Cr content (% by mass) in the oxide scale layer formed on the metal tube was determined from the average of three measurements. On the other hand, the ring-shaped test piece was held at 1000 ° C. for 300 hours in a gas atmosphere of 15% CH 4 -3% CO 2 -82% H 2 by volume to perform carburization and coking tests. For the coking resistance, the mass of the test piece before and after the test was measured, the increase due to the coke deposition was determined, and the amount of deposited coke per unit area (mg / cm 2 ) was determined. On the other hand, the carburization resistance was evaluated by the amount of C entering the base material. That is, metal chips were collected at a pitch of 0.5 mm in the depth direction from the surface of the test piece after the test, and the C amount (mass%) at a depth of 0.5 to 1.0 mm and 1.0 to 1.5 mm. After measuring the C amount (mass%) at the depth by chemical analysis and subtracting the base material C amount (mass%) before the test, the average value of both C amounts is the intrusion C amount (mass%) at 1 mm depth It was.
　各項目について、以下の基準を満たすものを合格とした。
（１）　Ｃｒ主体の酸化スケール層：ＥＤＸ分析でＣｒ濃度≧５０質量％
（２）　耐浸炭性：１ｍｍ深さにおける侵入Ｃ量≦１．５質量％
（３）　耐コーキング性：堆積Ｃ量≦３ｍｇ／ｃｍ２
　これらの結果を表２にまとめて示す。 About each item, what satisfy | filled the following criteria was set as the pass.
(1) Cr-based oxide scale layer: Cr concentration ≧ 50 mass% by EDX analysis
(2) Carburization resistance: amount of penetration C at a depth of 1 mm ≦ 1.5% by mass
(3) Coking resistance: amount of deposited C ≦ 3 mg / cm 2
These results are summarized in Table 2.
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
　なお、表２中数字は、各条件とも５個の試験片について、上記（１）、（２）および（３）のそれぞれを満たした個数を記している。たとえば、３／５は、５個のうち３個が合格である。本発明では金属管内面の全長で耐浸炭性と耐コーキング性に優れることを目的としているため、５個すべてが合格した場合が本発明の基準を満足すると判断した。 The numbers in Table 2 indicate the numbers satisfying each of the above (1), (2) and (3) for five test pieces for each condition. For example, 3/5 out of 5 passes. According to the present invention, the entire length of the inner surface of the metal tube is intended to be excellent in carburization resistance and caulking resistance. Therefore, it was judged that the case where all five passed satisfied the standard of the present invention.
　表２に示すように、化学組成が本発明に規定する条件を満たさない供試材番号１０を用いたＮｏ．２１および２２の例は、機械的処理を行ったにも拘らず、Ｃｒ主体の酸化スケール層が得られず、耐浸炭性および耐コーキング性とも劣っていた。供試材番号２および３を用いた例のうち、機械的処理を省略したＮｏ．７および１４の例では、５個のうちいくつかが基準を満足せず、管長手方向の耐浸炭性および耐コーキング性が不均一であった。供試材番号２の金属管を用いた例のうち、熱処理温度が低かったＮｏ．８および熱処理を実施しなかったＮｏ．９の例では、いくつかの試験片で浸炭やコーキングが発生した。 As shown in Table 2, No. 10 using test material number 10 whose chemical composition does not satisfy the conditions specified in the present invention. In Examples 21 and 22, a Cr-based oxide scale layer was not obtained despite mechanical treatment, and the carburization resistance and coking resistance were inferior. Among the examples using the test material numbers 2 and 3, No. in which the mechanical treatment was omitted. In the examples of 7 and 14, some of the five did not satisfy the criteria, and the carburization resistance and coking resistance in the longitudinal direction of the pipe were not uniform. Among the examples using the metal tube of test material number 2, the heat treatment temperature was low. No. 8 and No. in which heat treatment was not performed. In example 9, carburization and coking occurred in some specimens.
　一方、化学組成が本発明に規定する条件を満たす供試材番号１～９の金属管を用い、しかも、機械的処理を実施すると共に、本発明で規定される条件で熱処理を施した試験片は、いずれも上記（１）、（２）および（３）の基準をすべて満たしており、金属管長手方向の全長にわたり耐浸炭性および耐コーキング性に優れていた。 On the other hand, a test piece using a metal tube of specimen Nos. 1 to 9 whose chemical composition satisfies the conditions specified in the present invention, which was subjected to mechanical treatment and heat-treated under the conditions specified in the present invention. All satisfied the above criteria (1), (2) and (3), and were excellent in carburization resistance and coking resistance over the entire length in the metal tube longitudinal direction.
　本発明よれば、金属管内表面に均一にＣｒ主体の酸化スケール層を備える金属管を製造することができるので、浸炭性ガス環境における耐浸炭性および耐コーキング性に優れる。このため、本発明によって得られた金属管は、特に炭化水素ガス、ＣＯガスなどを含有する浸炭性ガス雰囲気で使用される管、例えば、石油精製、石油化学プラントなどにおける分解炉管、改質炉管、加熱炉管、熱交換器管等として使用するのに適している。 According to the present invention, since a metal tube having a uniform Cr-based oxide scale layer on the inner surface of the metal tube can be produced, it is excellent in carburization resistance and coking resistance in a carburizing gas environment. For this reason, the metal pipe obtained by the present invention is a pipe used in a carburizing gas atmosphere containing hydrocarbon gas, CO gas, etc., for example, a cracking furnace pipe in a petroleum refining, petrochemical plant, etc., reforming Suitable for use as furnace tube, heating furnace tube, heat exchanger tube and the like.

Claims (4)

  1. 　質量％で、２０～５５％のＣｒおよび２０～７０％のＮｉを含有する金属管の内表面に機械的処理を実施した後、
    １０５０～１２７０℃の温度範囲で、０．５～６０分保持する熱処理を実施して、
    金属管の少なくとも内表面にＣｒ主体の酸化スケール層を形成する
    ことを特徴とする金属管の製造方法。     After performing mechanical treatment on the inner surface of a metal tube containing 20-55% Cr and 20-70% Ni in mass%,
    In the temperature range of 1050 to 1270 ° C., heat treatment is performed for 0.5 to 60 minutes,
    A method of manufacturing a metal tube, comprising forming a Cr-based oxide scale layer on at least an inner surface of the metal tube.
  2. 　前記金属管が、質量％で、Ｃ：０．０１～０．６％、Ｓｉ：０．１～５％、Ｍｎ：０．１～１０％、Ｐ：０．０８％以下、Ｓ：０．０５％以下、Ｃｒ：２０～５５％、Ｎｉ：２０～７０％、Ｎ：０．００１～０．２５％およびＯ（酸素）：０．０２％以下を含有し、
    残部がＦｅおよび不純物からなる化学組成を有する
    ことを特徴とする請求項１に記載の金属管の製造方法。     The metal tube is, by mass%, C: 0.01 to 0.6%, Si: 0.1 to 5%, Mn: 0.1 to 10%, P: 0.08% or less, S: 0.0. 0.5% or less, Cr: 20 to 55%, Ni: 20 to 70%, N: 0.001 to 0.25% and O (oxygen): 0.02% or less,
    The metal tube manufacturing method according to claim 1, wherein the balance has a chemical composition comprising Fe and impurities.
  3. 　前記金属管が、質量％で、更に、下記（ａ）～（ｇ）に掲げる元素から選択される１種以上を含有する
    ことを特徴とする請求項２に記載の金属管の製造方法。
    （ａ）　Ｃｕ：５％以下、
    （ｂ）　Ｃｏ：５％以下、
    （ｃ）　Ｍｏ：３％以下、Ｗ：６％以下およびＴａ：６％以下から選択される１種以上、
    （ｄ）　Ｔｉ：１％以下およびＮｂ：２％以下から選択される１種または２種、
    （ｅ）　Ｂ：０．１％以下、Ｚｒ：０．１％以下およびＨｆ：０．５％以下から選択される１種以上、
    （ｆ）　Ｍｇ：０．１％以下、Ｃａ：０．１％以下およびＡｌ：１％以下から選択される１種以上、
    （ｇ）　Ｙ：０．１５％以下およびＬｎ族：０．１５％以下から選択される１種以上。     The method for producing a metal tube according to claim 2, wherein the metal tube further contains at least one element selected from the elements listed in the following (a) to (g) by mass%.
    (A) Cu: 5% or less,
    (B) Co: 5% or less,
    (C) one or more selected from Mo: 3% or less, W: 6% or less, and Ta: 6% or less,
    (D) Ti: 1% or less and Nb: 1 or 2 types selected from 2% or less,
    (E) one or more selected from B: 0.1% or less, Zr: 0.1% or less, and Hf: 0.5% or less,
    (F) one or more selected from Mg: 0.1% or less, Ca: 0.1% or less, and Al: 1% or less,
    (G) One or more selected from Y: 0.15% or less and Ln group: 0.15% or less.
  4. 　前記金属管が、管内面にリブ状の突起を有する
    ことを特徴とする請求項１から３までのいずれかに記載の金属管の製造方法。     The method of manufacturing a metal tube according to any one of claims 1 to 3, wherein the metal tube has a rib-like protrusion on the inner surface of the tube.
PCT/JP2010/052165 2009-02-16 2010-02-15 Method for producing metal tube WO2010093034A1 (en)

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* Cited by examiner, † Cited by third party
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JP2019502106A (en) * 2015-11-24 2019-01-24 フラマトムＦｒａｍａｔｏｍｅ Steam generator and corresponding manufacturing and use method
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01259156A (en) * 1988-04-08 1989-10-16 Sumitomo Metal Ind Ltd Austenitic stainless steel tube and its production
JPH01279741A (en) * 1988-05-02 1989-11-10 Osaka Gas Co Ltd Heat exchange device
JPH0339461A (en) * 1989-07-06 1991-02-20 Sumitomo Metal Ind Ltd Surface treated steel tube excellent in corrosion resistance and heat transfer efficiency and its production
JP2002121630A (en) * 2000-08-11 2002-04-26 Sumitomo Metal Ind Ltd Ni BASED ALLOY PRODUCT AND ITS PRODUCTION METHOD
WO2005078148A1 (en) * 2004-02-12 2005-08-25 Sumitomo Metal Industries, Ltd. Metal tube for use in carburizing gas atmosphere
JP2007284704A (en) * 2006-04-12 2007-11-01 Sumitomo Metal Ind Ltd METHOD FOR MANUFACTURING Cr-CONTAINING NICKEL-BASED ALLOY PIPE AND Cr-CONTAINING NICKEL-BASED ALLOY PIPE

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0645866B2 (en) * 1988-08-08 1994-06-15 住友金属工業株式会社 Heat treatment method for stainless steel for heater tubes
US5041309A (en) * 1990-02-28 1991-08-20 The Babcock & Wilcox Company Method of chromizing a workpiece by applying a coating containing chromium particles onto a ceramic carrier, positioning the carrier proximate the workpiece, and heating both carrier and workpiece to diffuse chromium particles into the workpiece
JPH0499860A (en) * 1990-08-15 1992-03-31 Honda Motor Co Ltd Surface treatment of titanium parts
AU739624B2 (en) * 1999-05-18 2001-10-18 Nippon Steel Corporation Martensitic stainless steel for seamless steel pipe
JP2003176824A (en) * 2001-12-11 2003-06-27 Minebea Co Ltd Fluid dynamic pressure bearing and spindle motor
JP3960069B2 (en) * 2002-02-13 2007-08-15 住友金属工業株式会社 Heat treatment method for Ni-base alloy tube
CN1280445C (en) * 2003-07-17 2006-10-18 住友金属工业株式会社 Stainless steel and stainless steel pipe having resistance to carburization and coking

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01259156A (en) * 1988-04-08 1989-10-16 Sumitomo Metal Ind Ltd Austenitic stainless steel tube and its production
JPH01279741A (en) * 1988-05-02 1989-11-10 Osaka Gas Co Ltd Heat exchange device
JPH0339461A (en) * 1989-07-06 1991-02-20 Sumitomo Metal Ind Ltd Surface treated steel tube excellent in corrosion resistance and heat transfer efficiency and its production
JP2002121630A (en) * 2000-08-11 2002-04-26 Sumitomo Metal Ind Ltd Ni BASED ALLOY PRODUCT AND ITS PRODUCTION METHOD
WO2005078148A1 (en) * 2004-02-12 2005-08-25 Sumitomo Metal Industries, Ltd. Metal tube for use in carburizing gas atmosphere
JP2007284704A (en) * 2006-04-12 2007-11-01 Sumitomo Metal Ind Ltd METHOD FOR MANUFACTURING Cr-CONTAINING NICKEL-BASED ALLOY PIPE AND Cr-CONTAINING NICKEL-BASED ALLOY PIPE

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2019502106A (en) * 2015-11-24 2019-01-24 フラマトムＦｒａｍａｔｏｍｅ Steam generator and corresponding manufacturing and use method
JP2022000539A (en) * 2017-10-04 2022-01-04 ノバ ケミカルズ コーポレイション Improved protection surface on stainless steel
JP7147026B2 (en) 2017-10-04 2022-10-04 ノバ ケミカルズ コーポレイション Improved protective surface on stainless steel
US11859291B2 (en) 2017-10-04 2024-01-02 Nova Chemicals (International) S.A. Protective surface on stainless steel
JP2020111828A (en) * 2019-01-16 2020-07-27 Ｊｆｅスチール株式会社 Manufacturing method of press-formed product and press-formed product
JP7107327B2 (en) 2019-01-16 2022-07-27 Ｊｆｅスチール株式会社 Press-molded product manufacturing method and press-molded product
JP7415144B2 (en) 2019-12-04 2024-01-17 日本製鉄株式会社 austenitic stainless steel
JP2020144138A (en) * 2020-05-14 2020-09-10 フラマトムＦｒａｍａｔｏｍｅ Steam generator, and manufacturing method and use method therefor

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