CN110918842A - Process for preparing common seamless steel grade steel pipe by adopting 35CrMo as plug material - Google Patents
Process for preparing common seamless steel grade steel pipe by adopting 35CrMo as plug material Download PDFInfo
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- CN110918842A CN110918842A CN201911194380.6A CN201911194380A CN110918842A CN 110918842 A CN110918842 A CN 110918842A CN 201911194380 A CN201911194380 A CN 201911194380A CN 110918842 A CN110918842 A CN 110918842A
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- cooling
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- 35crmo
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 52
- 239000010959 steel Substances 0.000 title claims abstract description 52
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 22
- 239000000463 material Substances 0.000 title claims abstract description 21
- 238000001816 cooling Methods 0.000 claims abstract description 40
- 238000005242 forging Methods 0.000 claims abstract description 16
- 238000000034 method Methods 0.000 claims abstract description 15
- 238000010438 heat treatment Methods 0.000 claims abstract description 11
- 239000002994 raw material Substances 0.000 claims abstract description 9
- 238000012545 processing Methods 0.000 claims abstract description 7
- 238000005096 rolling process Methods 0.000 claims abstract description 7
- 238000010301 surface-oxidation reaction Methods 0.000 claims abstract description 7
- 229910000746 Structural steel Inorganic materials 0.000 claims abstract description 4
- 238000005520 cutting process Methods 0.000 claims abstract description 4
- 238000000137 annealing Methods 0.000 claims description 6
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 5
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 5
- 239000004571 lime Substances 0.000 claims description 5
- 238000004321 preservation Methods 0.000 claims description 4
- 238000012958 reprocessing Methods 0.000 claims description 3
- 230000000630 rising effect Effects 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 238000007599 discharging Methods 0.000 claims 1
- 229910045601 alloy Inorganic materials 0.000 description 10
- 239000000956 alloy Substances 0.000 description 10
- 229910052799 carbon Inorganic materials 0.000 description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 238000005098 hot rolling Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000010583 slow cooling Methods 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 229910001563 bainite Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000005034 decoration Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000014509 gene expression Effects 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910001562 pearlite Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J1/00—Preparing metal stock or similar ancillary operations prior, during or post forging, e.g. heating or cooling
- B21J1/003—Selecting material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J1/00—Preparing metal stock or similar ancillary operations prior, during or post forging, e.g. heating or cooling
- B21J1/02—Preliminary treatment of metal stock without particular shaping, e.g. salvaging segregated zones, forging or pressing in the rough
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J1/00—Preparing metal stock or similar ancillary operations prior, during or post forging, e.g. heating or cooling
- B21J1/06—Heating or cooling methods or arrangements specially adapted for performing forging or pressing operations
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
- B21J5/002—Hybrid process, e.g. forging following casting
-
- 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
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention relates to the technical field of seamless steel pipes, in particular to a process for preparing a common seamless steel grade steel pipe by adopting 35CrMo as a plug material, which comprises the following steps: the method comprises the following steps: selecting a round blank made of high-quality structural steel 35CrMo to manufacture an outer water-cooling plug; step two: cutting a 35CrMo raw material in a round steel form into a proper length, and then directly blanking a round blank in a steel rolling workshop to produce a forging stock; step three: heating the forging stock produced in the step two to 980 +/-10 ℃ and then forging the forging stock into a piercing plug blank, stacking the piercing plug blank, and directly processing the piercing plug blank into an outer water-cooling plug after cooling; step four: and (3) performing air cooling on the external water-cooled top in the third step at 1000 +/-10 ℃ for 2h to realize surface oxidation treatment and heat treatment.
Description
Technical Field
The invention relates to the technical field of seamless steel pipes, in particular to a process for preparing a common seamless steel grade steel pipe by adopting 35CrMo as a plug material.
Background
The perforating top is a key tool and die for hot rolling and perforating seamless steel pipes, the quality of the service performance of the perforating top directly influences the hot rolling production of the seamless steel pipes, is a control factor of the production efficiency of the steel pipes, and simultaneously directly influences the consumption cost of hot rolling production tools and the labor intensity of workers, the perforating top is divided into an outer water-cooling perforating top and an inner water-cooling perforating top according to different cooling forms, the inner wall quality of the seamless steel pipes perforated by the inner water-cooling perforating top is good, so that the inner water-cooling perforating top is used for various steel pipes with high requirements on the inner wall quality in common alloy seamless pipes; according to different materials, the piercing plug is divided into a high-alloy piercing plug and a medium-alloy piercing plug. Seamless steel pipes are of various types and are classified into carbon seamless steel pipes (plain pipes), low-alloy seamless pipes, and medium-high alloy seamless pipes, depending on the material. The method is divided into the following steps according to the application: structural pipes, line pipes, oil pipes, drill pipes, nuclear power pipes, and the like. According to different varieties of seamless steel pipes, the materials and the structural forms of the used piercing plugs are different, generally, high-alloy inner water-cooling piercing plugs such as 3Cr2W8V, 25Cr2Ni3W8V, molybdenum-based powder plugs and the like are used for rolling high-alloy and high-alloy seamless pipes, and low-carbon inner water-cooling piercing plugs such as the rolled low-alloy steel: h13, 20Cr2Ni3MoW, 25Cr2Ni3MoW and the like, and the piercing plug for producing carbon seamless steel pipes (ordinary pipes) generally uses a low-carbon medium-alloy internal water-cooling plug, but the service life of the piercing plug is not longer than that of rolled low-alloy seamless steel, so that the cost performance is very low, the tool consumption cost of the carbon seamless steel pipes is increased, and the process for preparing the ordinary seamless steel grade steel pipes by adopting 35CrMo as the plug material is provided for solving the problems.
Disclosure of Invention
The invention aims to provide a process for preparing a common seamless steel grade steel pipe by adopting 35CrMo as a plug material, so as to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme:
a process for preparing a common seamless steel grade steel pipe by adopting 35CrMo as a plug material comprises the following steps:
the method comprises the following steps: selecting materials: selecting a round blank made of high-quality structural steel 35CrMo to manufacture an outer water-cooling plug;
step two: primary processing: cutting a 35CrMo raw material in a round steel form into a proper length, and then directly blanking a round blank in a steel rolling workshop to produce a forging stock;
step three: and (3) reprocessing: heating the forging stock produced in the step two to 980 +/-10 ℃ and then forging the forging stock into a piercing plug blank, stacking the piercing plug blank, and directly processing the piercing plug blank into an outer water-cooling plug after cooling;
step four: surface oxidation treatment and heat treatment: and (5) performing air cooling on the external water cooling top in the third step at 1000 +/-10 ℃ for 2h to realize surface oxidation treatment and heat treatment.
Preferably, in the third step, the temperature is reduced by using a mode of maintaining the temperature of lime and slowly cooling the lime to room temperature.
Preferably, in the cooling process in the third step, a residual heat annealing furnace is adopted to facilitate the annealing treatment of the blank.
Preferably, the external water-cooling top in the fourth step is introduced with controllable gas in the temperature rising process and the heat preservation stage after the temperature rises to 900 ℃ and the furnace is charged, and the furnace is discharged and slowly cooled when the temperature is reduced to 900 ℃ under the controllable atmosphere.
Compared with the prior art, the invention has the beneficial effects that:
compared with the 20Cr2Ni3MoW material internal water-cooling piercing plug with the same specification, the invention effectively saves the cost and has better economic value on the premise of ensuring the equivalent service life.
Detailed Description
Example (b): the invention provides a technical scheme that:
a process for preparing a common seamless steel grade steel pipe by adopting 35CrMo as a plug material, which is a process for preparing a common seamless steel grade steel pipe by adopting 35CrMo as a plug material, comprises the following steps:
the method comprises the following steps: selecting materials: selecting a round blank made of high-quality structural steel 35CrMo to manufacture an outer water-cooling plug;
step two: primary processing: cutting a 35CrMo raw material in a round steel form into a proper length, and then directly blanking a round blank in a steel rolling workshop to produce a forging stock;
step three: and (3) reprocessing: heating the forging stock produced in the step two to 980 +/-10 ℃ and then forging the forging stock into a piercing plug blank, stacking the piercing plug blank, and directly processing the piercing plug blank into an outer water-cooling plug after cooling;
step four: surface oxidation treatment and heat treatment: and (5) performing air cooling on the external water cooling top in the third step at 1000 +/-10 ℃ for 2h to realize surface oxidation treatment and heat treatment.
The mode that adopts lime heat preservation slow cooling to room temperature is cooled down in the step three, in the cooling process in the step three, adopt the waste heat annealing stove to do benefit to the blank and carry out annealing treatment, with the outer water-cooling top in the step four the intensification process and the heat preservation stage of after-loading of rising to 900 ℃ of temperature, furnace cooling is gone into to 900 ℃ of temperature under the controllable atmosphere and is gone out the stove slow cooling, foretell setting up the quality that perforation top production comes out of assurance that can be better, thereby the effectual life who guarantees the perforation top, better assurance the benefit of firm.
Comparative example:
sampling and detecting raw materials and the plug produced by the method:
the raw material is 0Cr2Ni3MoW piercing point, the surface of which is provided with a layer of black oxide film, HRC 36-39 б b 1080-.
The plug is characterized in that a layer of black oxide film is arranged on the surface of a 35CrMo piercing plug, HRC (Rockwell hardness) 32-36 б b890-950MPa Ak is 17-21J (5 body samples), and the microstructure is martensite, bainite and pearlite.
The actual production of seamless steel grade steel pipes is carried out on the raw materials and the plug produced in the invention: the 35CrMo outer water-cooling piercing plug is used for trial rolling of 20# seamless steel pipes on 140 units and 159 units of certain steel pipes, and the specifications of the piercing plug are as follows: phi 138 and phi 142, the service life is 189 and 175, and the service life of the 20Cr2Ni3MoW material with the same specification is 192 and 170 respectively.
In summary, the plug produced by the invention has little difference with the raw materials in terms of Rockwell hardness, tensile strength and impact toughness, and the average service life of the two piercing plugs is equivalent in the actual use process, but compared with the raw materials, the plug produced by the technology can save 5000 yuan per ton, so that the 35CrMo outer water-cooling piercing plug has better economic value when rolling carbon seamless steel pipes (common pipes) and higher user satisfaction.
The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts of the present invention. The foregoing is only a preferred embodiment of the present invention, and it should be noted that there are objectively infinite specific structures due to the limited character expressions, and it will be apparent to those skilled in the art that a plurality of modifications, decorations or changes may be made without departing from the principle of the present invention, and the technical features described above may be combined in a suitable manner; such modifications, variations, combinations, or adaptations of the invention using its spirit and scope, as defined by the claims, may be directed to other uses and embodiments.
Claims (4)
1. A process for preparing a common seamless steel grade steel pipe by using 35CrMo as a plug material is characterized by comprising the following steps of: the method comprises the following steps:
the method comprises the following steps: selecting materials: selecting a round blank made of high-quality structural steel 35CrMo to manufacture an outer water-cooling plug;
step two: primary processing: cutting a 35CrMo raw material in a round steel form into a proper length, and then directly blanking a round blank in a steel rolling workshop to produce a forging stock;
step three: and (3) reprocessing: heating the forging stock produced in the step two to 980 +/-10 ℃ and then forging the forging stock into a piercing plug blank, stacking the piercing plug blank, and directly processing the piercing plug blank into an outer water-cooling plug after cooling;
step four: surface oxidation treatment and heat treatment: and (5) performing air cooling on the external water cooling top in the third step at 1000 +/-10 ℃ for 2h to realize surface oxidation treatment and heat treatment.
2. The process for preparing the common seamless steel grade steel pipe by adopting 35CrMo as the plug material according to claim 1, is characterized in that: and in the third step, the temperature is reduced by adopting a mode of maintaining the temperature of lime and slowly cooling the lime to room temperature.
3. The process for preparing the common seamless steel grade steel pipe by adopting 35CrMo as the plug material according to claim 1, is characterized in that: in the cooling process in the third step, the residual heat annealing furnace is adopted to facilitate the annealing treatment of the blank.
4. The process for preparing the common seamless steel grade steel pipe by adopting 35CrMo as the plug material according to claim 1, is characterized in that: and C, introducing controllable gas into the external water-cooling top in the fourth step in the temperature rising process and the heat preservation stage after the temperature rises to 900 ℃ and the furnace is charged, and discharging and slowly cooling the furnace when the temperature is reduced to 900 ℃ in a controllable atmosphere.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911194380.6A CN110918842A (en) | 2019-11-28 | 2019-11-28 | Process for preparing common seamless steel grade steel pipe by adopting 35CrMo as plug material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911194380.6A CN110918842A (en) | 2019-11-28 | 2019-11-28 | Process for preparing common seamless steel grade steel pipe by adopting 35CrMo as plug material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110918842A true CN110918842A (en) | 2020-03-27 |
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|---|---|---|---|
| CN201911194380.6A Pending CN110918842A (en) | 2019-11-28 | 2019-11-28 | Process for preparing common seamless steel grade steel pipe by adopting 35CrMo as plug material |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04147706A (en) * | 1990-10-12 | 1992-05-21 | Kawasaki Steel Corp | Plug for producing seamless steel pipe |
| CN1112165A (en) * | 1995-04-19 | 1995-11-22 | 宝山钢铁(集团)公司 | Steel pipe perforating heading material |
| CN101077560A (en) * | 2007-07-02 | 2007-11-28 | 登封市泰隆钨钼材料有限公司 | Forging molybdenum plug and preparation method thereof |
| CN101381850A (en) * | 2008-10-23 | 2009-03-11 | 衡阳华菱连轧管有限公司 | Alloyed steel plug for steel tube perforating and production method |
| CN104325259A (en) * | 2014-08-29 | 2015-02-04 | 南通市嘉业机械制造有限公司 | Manufacturing method of seamless steel pipe piercing plug |
| CN104646955A (en) * | 2014-12-18 | 2015-05-27 | 江苏皓宇合金机械有限公司 | Method for preparing 20CrNi4 piercing plug |
-
2019
- 2019-11-28 CN CN201911194380.6A patent/CN110918842A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04147706A (en) * | 1990-10-12 | 1992-05-21 | Kawasaki Steel Corp | Plug for producing seamless steel pipe |
| CN1112165A (en) * | 1995-04-19 | 1995-11-22 | 宝山钢铁(集团)公司 | Steel pipe perforating heading material |
| CN101077560A (en) * | 2007-07-02 | 2007-11-28 | 登封市泰隆钨钼材料有限公司 | Forging molybdenum plug and preparation method thereof |
| CN101381850A (en) * | 2008-10-23 | 2009-03-11 | 衡阳华菱连轧管有限公司 | Alloyed steel plug for steel tube perforating and production method |
| CN104325259A (en) * | 2014-08-29 | 2015-02-04 | 南通市嘉业机械制造有限公司 | Manufacturing method of seamless steel pipe piercing plug |
| CN104646955A (en) * | 2014-12-18 | 2015-05-27 | 江苏皓宇合金机械有限公司 | Method for preparing 20CrNi4 piercing plug |
Non-Patent Citations (2)
| Title |
|---|
| 《钢铁》编写组: "《钢铁》", 31 March 1976, 上海人民出版社 * |
| 吴国梁: "无缝钢管斜轧穿孔顶头的应用", 《钢管技术》 * |
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Application publication date: 20200327 |
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