CN112474870A - Production process of 316 food-grade clean stainless steel seamless pipe - Google Patents
Production process of 316 food-grade clean stainless steel seamless pipe Download PDFInfo
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- CN112474870A CN112474870A CN202011298293.8A CN202011298293A CN112474870A CN 112474870 A CN112474870 A CN 112474870A CN 202011298293 A CN202011298293 A CN 202011298293A CN 112474870 A CN112474870 A CN 112474870A
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- 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
- B21C37/10—Making tubes with riveted seams or with non-welded and non-soldered seams
- B21C37/107—Tube treating or manipulating combined with or specially adapted for use in connection with tube-making machines, e.g. drawing-off devices, cutting-off
-
- 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
- B21C1/00—Manufacture of metal sheets, metal wire, metal rods, metal tubes by drawing
- B21C1/16—Metal drawing by machines or apparatus in which the drawing action is effected by other means than drums, e.g. by a longitudinally-moved carriage pulling or pushing the work or stock for making metal sheets, bars, or tubes
- B21C1/22—Metal drawing by machines or apparatus in which the drawing action is effected by other means than drums, e.g. by a longitudinally-moved carriage pulling or pushing the work or stock for making metal sheets, bars, or tubes specially adapted for making tubular articles
-
- 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
- B21C37/30—Finishing tubes, e.g. sizing, burnishing
-
- 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
- C21D1/19—Hardening; Quenching with or without subsequent tempering by interrupted 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
- 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
- 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
- C23C8/28—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 more than one element being applied in one step
- C23C8/30—Carbo-nitriding
- C23C8/32—Carbo-nitriding of ferrous surfaces
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- 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)
- Chemical Kinetics & Catalysis (AREA)
- Heat Treatment Of Articles (AREA)
- Metal Extraction Processes (AREA)
Abstract
The invention discloses a production process of a 316 food-grade clean stainless steel seamless pipe, which sequentially comprises the following steps: the method comprises the following steps: perforating the tube blank, and step two: removing impurities by acid washing, and step three: drawing the tube blank, and step four: grinding and straightening, and step five: bright annealing, step six: and (5) carrying out co-permeation treatment, and carrying out a seventh step: step eight, step eight: and (7) tempering, step nine: and (7) checking and warehousing. The invention can improve the wall thickness uniformity of the food-grade stainless steel pipe and can improve the surface finish and corrosion resistance of the food-grade stainless steel pipe.
Description
[ technical field ] A method for producing a semiconductor device
The invention relates to the technical field of seamless steel tube production, in particular to the technical field of a production process of a 316 food-grade clean stainless steel seamless tube.
[ background of the invention ]
The food-grade stainless steel pipe is widely applied in various industries, and the requirement on the smoothness of the inner surface of the food-grade stainless steel pipe is high. The relationship between the quality of the treatment of the inner surface and the outer surface of the stainless steel pipe and the corrosion resistance is very close, and the higher the surface smoothness is, the more difficult the adhesion of impurities is, and the better the corrosion resistance is; when the surface smoothness of the inner surface of the pipe is higher, the retention of the inner flow liquid medium is less, the flushing is more favorable, and the corrosion resistance is greatly improved. In the existing production technology, the roughness control of the inner surface of a product is not very accurate, the yield is low, and the production cost is high.
[ summary of the invention ]
The invention aims to solve the problems in the prior art, and provides a production process of a 316 food-grade clean stainless steel seamless pipe, which can improve the wall thickness uniformity of the food-grade stainless steel pipe and improve the surface finish and corrosion resistance of the food-grade stainless steel pipe.
In order to realize the aim, the invention provides a production process of a 316 food-grade clean stainless steel seamless tube, which sequentially comprises the following steps:
the method comprises the following steps: perforating a tube blank, namely heating the raw material tube blank at 1150-plus-1200 ℃, then perforating the heated tube blank on a perforating machine for 20-30min according to the wall thickness of different steel tubes, wherein the perforating temperature is 1100-plus-1150 ℃, and heading;
step two: pickling and impurity removal, namely immersing the raw material pipe blank treated in the step one in pickling solution for pickling and impurity removal, washing the raw material pipe blank with clear water after pickling, and draining;
step three: drawing the tube blank, namely performing surface oil coating lubrication on the raw material tube blank processed in the step two, feeding the raw material tube blank into a drawing machine, performing drawing operation through the matching of an inner die sleeve and a drawing die sleeve, and repeating the operation for multiple times;
step four: polishing and straightening, namely polishing and expanding the raw material pipe blank processed in the step three, straightening the raw material pipe blank after polishing and expanding, and washing and drying the raw material pipe blank;
step five: bright annealing, namely conveying the raw material pipe blank treated in the step four into a heat treatment furnace for bright annealing at the temperature scale of 1100-1120 ℃, and introducing pure hydrogen as protective atmosphere in the bright annealing process;
step six: co-cementation, namely feeding the raw material pipe blank treated in the fifth step into a co-cementation furnace for co-cementation, and preserving the temperature for 30-50min after the thickness of a designated co-cementation layer is reached;
step seven: step-quenching, namely feeding the raw material pipe blank processed in the step six into a quenching furnace for step-quenching;
step eight: tempering, namely tempering the raw material pipe blank treated in the step seven;
step nine: and (5) inspecting and warehousing, namely drying, straightening, pipe cutting, finishing, inspecting and flaw detecting the raw material pipe blanks treated in the step eight, and packaging and warehousing after the raw material pipe blanks are qualified.
Preferably, in the third step, the inner die sleeve is in clearance fit with the drawing die sleeve, and the inner die sleeve can rotate under the action of the circumferential stress difference.
Preferably, a dehumidifier is arranged in the heat treatment furnace in the fifth step, the pressure of the protective atmosphere is 25-30 kBar, and the bright annealing time is 2-3 h.
Preferably, the thickness of the co-permeation layer in the co-permeation treatment of the sixth step is 80-90 μm, and the toughness of the co-permeation layer is ensured when the temperature is kept at 520-580 ℃.
Preferably, nitrogen, ammonia and carbon monoxide are introduced in the process of the step six co-cementation, wherein the introduction amount of the nitrogen is 8-9L/h, the introduction amount of the ammonia is 3-5L/h, and the introduction amount of the carbon monoxide is 6-8L/h.
The invention has the beneficial effects that: according to the invention, the drawing die is adopted for drawing, the inner die sleeve and the drawing die sleeve are in clearance fit, so that the friction resistance between the inner die sleeve and the drawing die sleeve can be avoided, the inner die sleeve can be ensured to rotate under the action of the circumferential stress difference, the wall thickness uniformity, the surface smoothness and the product quality of a finished product can be improved, and the co-permeation layer and the steel pipe are combined more tightly through graded quenching after the co-permeation treatment, the wall thickness uniformity of the food-grade stainless steel pipe can be improved, and the surface finish and the corrosion resistance of the food-grade stainless steel pipe can be improved.
The features and advantages of the present invention will be described in detail by way of examples.
[ detailed description ] embodiments
The invention relates to a production process of a 316 food-grade clean stainless steel seamless pipe, which sequentially comprises the following steps:
the method comprises the following steps: perforating a tube blank, namely heating the raw material tube blank at 1150-plus-1200 ℃, then perforating the heated tube blank on a perforating machine for 20-30min according to the wall thickness of different steel tubes, wherein the perforating temperature is 1100-plus-1150 ℃, and heading;
step two: pickling and impurity removal, namely immersing the raw material pipe blank treated in the step one in pickling solution for pickling and impurity removal, washing the raw material pipe blank with clear water after pickling, and draining;
step three: drawing the tube blank, namely performing surface oil coating lubrication on the raw material tube blank processed in the step two, feeding the raw material tube blank into a drawing machine, performing drawing operation through the matching of an inner die sleeve and a drawing die sleeve, and repeating the operation for multiple times;
step four: polishing and straightening, namely polishing and expanding the raw material pipe blank processed in the step three, straightening the raw material pipe blank after polishing and expanding, and washing and drying the raw material pipe blank;
step five: bright annealing, namely conveying the raw material pipe blank treated in the step four into a heat treatment furnace for bright annealing at the temperature scale of 1100-1120 ℃, and introducing pure hydrogen as protective atmosphere in the bright annealing process;
step six: co-cementation, namely feeding the raw material pipe blank treated in the fifth step into a co-cementation furnace for co-cementation, and preserving the temperature for 30-50min after the thickness of a designated co-cementation layer is reached;
step seven: step-quenching, namely feeding the raw material pipe blank processed in the step six into a quenching furnace for step-quenching;
step eight: tempering, namely tempering the raw material pipe blank treated in the step seven;
step nine: and (5) inspecting and warehousing, namely drying, straightening, pipe cutting, finishing, inspecting and flaw detecting the raw material pipe blanks treated in the step eight, and packaging and warehousing after the raw material pipe blanks are qualified.
The inner die sleeve and the drawing die sleeve are in clearance fit in the third step, the inner die sleeve can rotate under the action of circumferential stress difference, a dehumidifier is arranged in the heat treatment furnace in the fifth step, the pressure of protective atmosphere is 25-30 kBar, the bright annealing time is 2-3h, the thickness of the co-permeation layer in the co-permeation treatment in the sixth step is 80-90 mu m, the toughness of the co-permeation layer is realized when heat preservation is carried out at the temperature of 520-plus-material 580 ℃, nitrogen, ammonia and carbon monoxide gas are introduced in the process of the six co-permeation step, the introduction amount of the nitrogen is 8-9L/h, the introduction amount of the ammonia is 3-5L/h, and the introduction amount of the carbon monoxide gas is 6-8L/h.
According to the invention, the drawing die is adopted for drawing, the inner die sleeve and the drawing die sleeve are in clearance fit, so that the friction resistance between the inner die sleeve and the drawing die sleeve can be avoided, the inner die sleeve can be ensured to rotate under the action of the circumferential stress difference, the wall thickness uniformity, the surface smoothness and the product quality of a finished product can be improved, and the co-permeation layer and the steel pipe are combined more tightly through graded quenching after the co-permeation treatment, the wall thickness uniformity of the food-grade stainless steel pipe can be improved, and the surface finish and the corrosion resistance of the food-grade stainless steel pipe can be improved.
The above embodiments are illustrative of the present invention, and are not intended to limit the present invention, and any simple modifications of the present invention are within the scope of the present invention.
Claims (5)
1. A production process of a 316 food-grade clean stainless steel seamless tube is characterized by comprising the following steps: the method sequentially comprises the following steps:
the method comprises the following steps: perforating a tube blank, namely heating the raw material tube blank at 1150-plus-1200 ℃, then perforating the heated tube blank on a perforating machine for 20-30min according to the wall thickness of different steel tubes, wherein the perforating temperature is 1100-plus-1150 ℃, and heading;
step two: pickling and impurity removal, namely immersing the raw material pipe blank treated in the step one in pickling solution for pickling and impurity removal, washing the raw material pipe blank with clear water after pickling, and draining;
step three: drawing the tube blank, namely performing surface oil coating lubrication on the raw material tube blank processed in the step two, feeding the raw material tube blank into a drawing machine, performing drawing operation through the matching of an inner die sleeve and a drawing die sleeve, and repeating the operation for multiple times;
step four: polishing and straightening, namely polishing and expanding the raw material pipe blank processed in the step three, straightening the raw material pipe blank after polishing and expanding, and washing and drying the raw material pipe blank;
step five: bright annealing, namely conveying the raw material pipe blank treated in the step four into a heat treatment furnace for bright annealing at the temperature scale of 1100-1120 ℃, and introducing pure hydrogen as protective atmosphere in the bright annealing process;
step six: co-cementation, namely feeding the raw material pipe blank treated in the fifth step into a co-cementation furnace for co-cementation, and preserving the temperature for 30-50min after the thickness of a designated co-cementation layer is reached;
step seven: step-quenching, namely feeding the raw material pipe blank processed in the step six into a quenching furnace for step-quenching;
step eight: tempering, namely tempering the raw material pipe blank treated in the step seven;
step nine: and (5) inspecting and warehousing, namely drying, straightening, pipe cutting, finishing, inspecting and flaw detecting the raw material pipe blanks treated in the step eight, and packaging and warehousing after the raw material pipe blanks are qualified.
2. The production process of the 316 food-grade clean stainless steel seamless tube according to claim 1, wherein the production process comprises the following steps: and in the third step, the inner die sleeve is in clearance fit with the drawing die sleeve, and the inner die sleeve can rotate under the action of the circumferential stress difference.
3. The production process of the 316 food-grade clean stainless steel seamless tube according to claim 1, wherein the production process comprises the following steps: and a dehumidifier is arranged in the heat treatment furnace in the fifth step, the pressure of the protective atmosphere is 25-30 kBar, and the bright annealing time is 2-3 h.
4. The production process of the 316 food-grade clean stainless steel seamless tube according to claim 1, wherein the production process comprises the following steps: the thickness of the co-permeation layer in the co-permeation treatment of the sixth step is 80-90 μm, and the toughness of the co-permeation layer is achieved when the heat preservation is carried out at the temperature of 520-580 ℃.
5. The production process of the 316 food-grade clean stainless steel seamless tube according to claim 1, wherein the production process comprises the following steps: and introducing nitrogen, ammonia gas and carbon monoxide gas in the hexachloro-cementation process, wherein the introduction amount of the nitrogen gas is 8-9L/h, the introduction amount of the ammonia gas is 3-5L/h, and the introduction amount of the carbon monoxide gas is 6-8L/h.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011298293.8A CN112474870A (en) | 2020-11-19 | 2020-11-19 | Production process of 316 food-grade clean stainless steel seamless pipe |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011298293.8A CN112474870A (en) | 2020-11-19 | 2020-11-19 | Production process of 316 food-grade clean stainless steel seamless pipe |
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| CN112474870A true CN112474870A (en) | 2021-03-12 |
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| CN202011298293.8A Pending CN112474870A (en) | 2020-11-19 | 2020-11-19 | Production process of 316 food-grade clean stainless steel seamless pipe |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6029714A (en) * | 1994-04-14 | 2000-02-29 | Sumitomo Metal Industries, Ltd. | Stainless steel pipe of bright annealing finish type, having highly-smoothed inner surface and method for producing the same |
| US20020164260A1 (en) * | 2001-02-27 | 2002-11-07 | Takeshi Koga | High-hardness martensitic stainless steel excellent in corrosion resistance |
| JP2007167912A (en) * | 2005-12-22 | 2007-07-05 | Sumitomo Metal Ind Ltd | Method for producing stainless steel tube |
| CN202246831U (en) * | 2011-10-11 | 2012-05-30 | 祁标 | Complete set of sealed box type gas carbonitriding furnace equipment |
| CN104174690A (en) * | 2014-07-21 | 2014-12-03 | 苏州贝思特金属制品有限公司 | Production process of sanitary stainless steel seamless pipe |
| CN104551667A (en) * | 2013-10-16 | 2015-04-29 | 无锡江南高精度冷拔管有限公司 | Cold-rolled high-hardness seamless steel pipe manufacturing method |
| CN107267731A (en) * | 2017-07-01 | 2017-10-20 | 浙江义腾特种钢管有限公司 | A kind of production technology for automobile exhaust system stainless steel tube |
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-
2020
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| US20020164260A1 (en) * | 2001-02-27 | 2002-11-07 | Takeshi Koga | High-hardness martensitic stainless steel excellent in corrosion resistance |
| JP2007167912A (en) * | 2005-12-22 | 2007-07-05 | Sumitomo Metal Ind Ltd | Method for producing stainless steel tube |
| CN202246831U (en) * | 2011-10-11 | 2012-05-30 | 祁标 | Complete set of sealed box type gas carbonitriding furnace equipment |
| CN104551667A (en) * | 2013-10-16 | 2015-04-29 | 无锡江南高精度冷拔管有限公司 | Cold-rolled high-hardness seamless steel pipe manufacturing method |
| CN104174690A (en) * | 2014-07-21 | 2014-12-03 | 苏州贝思特金属制品有限公司 | Production process of sanitary stainless steel seamless pipe |
| JP2018035381A (en) * | 2016-08-29 | 2018-03-08 | 新日鐵住金株式会社 | Production method of stainless steel tube |
| CN107267731A (en) * | 2017-07-01 | 2017-10-20 | 浙江义腾特种钢管有限公司 | A kind of production technology for automobile exhaust system stainless steel tube |
| CN111230515A (en) * | 2020-02-14 | 2020-06-05 | 南京沃尔德特钢有限公司 | Production method of seamless stainless steel tube for boiler heat exchanger |
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