CN102284486A - Process for manufacturing seamless steel tubes by hot rolling - Google Patents
Process for manufacturing seamless steel tubes by hot rolling Download PDFInfo
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- CN102284486A CN102284486A CN2011102444709A CN201110244470A CN102284486A CN 102284486 A CN102284486 A CN 102284486A CN 2011102444709 A CN2011102444709 A CN 2011102444709A CN 201110244470 A CN201110244470 A CN 201110244470A CN 102284486 A CN102284486 A CN 102284486A
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 32
- 239000010959 steel Substances 0.000 title claims abstract description 32
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 29
- 238000000034 method Methods 0.000 title abstract description 13
- 230000008569 process Effects 0.000 title abstract description 11
- 238000005098 hot rolling Methods 0.000 title abstract 3
- 238000005096 rolling process Methods 0.000 claims abstract description 41
- 238000010438 heat treatment Methods 0.000 claims abstract description 40
- 238000005242 forging Methods 0.000 claims description 10
- 238000003303 reheating Methods 0.000 claims description 10
- 238000000605 extraction Methods 0.000 claims description 8
- 230000000717 retained effect Effects 0.000 claims description 8
- 238000004804 winding Methods 0.000 claims description 8
- 210000000481 breast Anatomy 0.000 claims description 4
- 239000011248 coating agent Substances 0.000 claims description 4
- 238000000576 coating method Methods 0.000 claims description 4
- 230000007797 corrosion Effects 0.000 claims description 4
- 238000005260 corrosion Methods 0.000 claims description 4
- 230000007547 defect Effects 0.000 claims description 4
- 238000005553 drilling Methods 0.000 claims description 4
- 239000012535 impurity Substances 0.000 claims description 4
- 230000006698 induction Effects 0.000 claims description 4
- 230000002401 inhibitory effect Effects 0.000 claims description 4
- 238000007689 inspection Methods 0.000 claims description 4
- 229910052742 iron Inorganic materials 0.000 claims description 4
- 229910052748 manganese Inorganic materials 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- 229910052759 nickel Inorganic materials 0.000 claims description 4
- 238000007639 printing Methods 0.000 claims description 4
- 230000009467 reduction Effects 0.000 claims description 4
- 238000004513 sizing Methods 0.000 claims description 4
- 239000007921 spray Substances 0.000 claims description 4
- 229910052720 vanadium Inorganic materials 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 229910052726 zirconium Inorganic materials 0.000 claims description 4
- 230000008901 benefit Effects 0.000 abstract description 2
- 238000004080 punching Methods 0.000 abstract 1
- 238000005516 engineering process Methods 0.000 description 4
- 229910001566 austenite Inorganic materials 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
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- Forging (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
The invention discloses a process for manufacturing seamless steel tubes by hot rolling, comprising the following steps of: (1) heating tube blanks; (2) punching; (3) tandem rolling; (4) concentrating the punched tubular billets in a heating furnace after the tandem rolling is carried out and then heating; (5) mounting a tube knockout machine with five machine racks in back of a tandem rolling machine set with eight machine racks to knock out pierced billets after being tandem rolled for eight times from a mandril and start a next procedure which is a 20-machine-rack tension reducing procedure; (6) configuring a tension reducing machine rack with 20 machine racks and three rollers; introducing the knocked-out pierced billets into the tension reducing machine rack with the 20 machine racks and the three rollers to roll so that the heat finished product steel tubes are obtained; (7) forming the finished product steel tubes after finishing the heat finished product steel tubes. Production efficiency and finished product quality are notably improved by further searching and improving the process for manufacturing the seamless steel tubes by hot rolling, thereby generating more and better steel tubes per unit time and improving economic benefit of enterprises.
Description
Technical field
The present invention relates to the hot rolled seamless steel tube manufacturing process, belong to metal rolled technical field.
Background technology
Existing hot rolled seamless steel tube production process is solid pipe (or steel ingot) is bored a hole and to be rolled into the steel pipe of reservation shape, size and performance; Whole process mainly contains three distortion operations: (1) perforation-solid pipe (steel ingot) pierced billet is become hollow hollow forging; (2) tube rolling-with the wall thickness of hollow forging rolls into preliminary dimension or near the hollow billet of preliminary dimension; (3) decide the tube reducing-external diameter of hollow billet the is rolled into hot production tube of preliminary dimension.
Deciding the tube reducing operation and need dispose a large amount of standby frames in the hot rolled seamless steel tube production technology forming the pass schedule of different standby series, thereby satisfies the hollow billet distortion of rolling back different size, and final production goes out the finished product seamless steel pipe of different size group distance; When the roll stand of size-reducing mill more for a long time, then need more standby frame.Therefore, generally speaking, size-reducing mill and standby frame are the maximum operations of investment in the whole piece seamless steel tube production chain.
Because modified heat treatment cost is higher, enhances competitiveness for reducing production costs, and steel pipe line normalizing process technology again occurred.Its essence is that the steel pipe temperature that tandem rolling is taken off behind the rod reduces to below the Ac1, to ferritic transformation, carry out once phase-change before making steel pipe enter reheating furnace by austenite, in reheating furnace, reheat austenitizing after, utilize recrystallization refine austenite crystal grain.Like this through open subtract after the steel pipe crystal grain of air cooling can be than refinement to some extent in the past, generally can bring up to 9～10 grades from 6～7 grades, toughness also increases.
Therefore, the maximum single processing apparatus of investment in the hot rolled seamless steel tube production technology, i.e. size-reducing mill, actual production usefulness can only have been given play to the effect less than its half capacity of equipment.
Summary of the invention
At the deficiencies in the prior art, one of purpose of the present invention is to provide a kind of hot rolled seamless steel tube manufacturing process.
For achieving the above object, the present invention adopts following technical scheme:
A kind of hot rolled seamless steel tube manufacturing process, pipe composition quality percentage is: C 0.25～0.35%, Si 0.1～0.5%, Ni 5.0-8.5%, Zr 3.5-4.8%, Mn 1.0～2.0%, V 0.05～0.25%, N 0.015～0.030%, Fe surplus and inevitable impurity;
Described manufacturing process is:
(1) pipe is heated in heating furnace;
(2) two punches being set bores a hole to the pipe after heating;
(3) 8 frame tandem rolling tube machines are set behind punch, the hollow billet after the perforation is through on the retained mandrel in advance, extend rolling continuously to the hollow billet after boring a hole by 8 frames of continuous layout and the wrong mutually retained mandrel tandem rolling tube machine of roll gap of adjacent breast roller;
(4) hollow billet behind the drilling/rolling is concentrated in the reheating furnace heats again;
(5) behind 8 frame tandem rolling units, 5 frame winding arbor extraction presses are set, the hollow forging behind 8 tandem rollings is deviate to enter next operation-20 frame stretch reducing operation from plug;
(6) configuration 20 frame three-roller tension reducing mill framves after 5 frame winding arbor extraction press groups take off hollow forging behind the pipe and enter 20 frame three-roller tension reducing mill framves and be rolled, and form hot fished pipe; Sizing reduction can reach 35%～42%, and wall thickness reducing amount can reach 18%～24%, and lengthening coefficient can reach 4.3～5.1, and muzzle velocity can reach 13m/s;
(7) will form fished pipe after the hot fished pipe finishing.
Refinement more: in the described step (1), with heating of pipe blank to 1290～1400 ℃.
Step (1), (4) described heating furnace or reheating furnace comprise inclined-bottom heating furnace, step heating-furnace, rotary heating furnace, tunnel heating furnace, induction heating furnace.
Described heating, its temperature range are 1100～1350 ℃.
Described punch is that vertical cone mill, cone-type piercer machine, Di are given up youngster's punch, pushing piercing machine or press piercing mill.
Described pipe mill is MPM tandem rolling tube machine, PQF three-roller tandem rolling tube machine, roller trio skew rolling pipe machine or push-bench, and wherein hot-rolled temperature is 750-900 ℃.
Described step finishing comprise blow ash, aligning, excision burr tail, hand inspection, defect detecting test, the water pressure test, spray printing sign, corrosion-inhibiting coating, measure each operation or wherein any practical need the combination operation of operation.
The specific embodiment
In order to make those skilled in the art person understand the present invention program better, and above-mentioned purpose of the present invention, feature and advantage can be become apparent more, below embodiment be that the present invention is further detailed explanation:
Embodiment one
A kind of hot rolled seamless steel tube manufacturing process, pipe composition quality percentage is: C 0.35%, Si 0.5%, Ni 8.5%, Zr 4.8%, Mn 2.0%, V 0.25%, N 0.030%, Fe surplus and inevitable impurity;
Described manufacturing process is:
(1) pipe is heated in heating furnace;
(2) two punches being set bores a hole to the pipe after heating;
(3) 8 frame tandem rolling tube machines are set behind punch, the hollow billet after the perforation is through on the retained mandrel in advance, extend rolling continuously to the hollow billet after boring a hole by 8 frames of continuous layout and the wrong mutually retained mandrel tandem rolling tube machine of roll gap of adjacent breast roller;
(4) hollow billet behind the drilling/rolling is concentrated in the reheating furnace heats again;
(5) behind 8 frame tandem rolling units, 5 frame winding arbor extraction presses are set, the hollow forging behind 8 tandem rollings is deviate to enter next operation-20 frame stretch reducing operation from plug;
(6) configuration 20 frame three-roller tension reducing mill framves after 5 frame winding arbor extraction press groups take off hollow forging behind the pipe and enter 20 frame three-roller tension reducing mill framves and be rolled, and form hot fished pipe; Sizing reduction can reach 35%～42%, and wall thickness reducing amount can reach 18%～24%, and lengthening coefficient can reach 4.3～5.1, and muzzle velocity can reach 13m/s;
(7) will form fished pipe after the hot fished pipe finishing.
Refinement more: in the described step (1), with heating of pipe blank to 1400 ℃.
Step (1), (4) described heating furnace or reheating furnace comprise inclined-bottom heating furnace, step heating-furnace, rotary heating furnace, tunnel heating furnace, induction heating furnace.
Described heating, its temperature range are 1350 ℃.
Described punch is that vertical cone mill, cone-type piercer machine, Di are given up youngster's punch, pushing piercing machine or press piercing mill.
Described pipe mill is MPM tandem rolling tube machine, PQF three-roller tandem rolling tube machine, roller trio skew rolling pipe machine or push-bench, and wherein hot-rolled temperature is 900 ℃.
Described step finishing comprise blow ash, aligning, excision burr tail, hand inspection, defect detecting test, the water pressure test, spray printing sign, corrosion-inhibiting coating, measure each operation or wherein any practical need the combination operation of operation.
Embodiment two
A kind of hot rolled seamless steel tube manufacturing process, pipe composition quality percentage is: C 0.25%, Si 0.1%, Ni 5.0%, Zr 3.5%, Mn 1.0%, V 0.05%, N 0.015%, Fe surplus and inevitable impurity;
Described manufacturing process is:
(1) pipe is heated in heating furnace;
(2) two punches being set bores a hole to the pipe after heating;
(3) 8 frame tandem rolling tube machines are set behind punch, the hollow billet after the perforation is through on the retained mandrel in advance, extend rolling continuously to the hollow billet after boring a hole by 8 frames of continuous layout and the wrong mutually retained mandrel tandem rolling tube machine of roll gap of adjacent breast roller;
(4) hollow billet behind the drilling/rolling is concentrated in the reheating furnace heats again;
(5) behind 8 frame tandem rolling units, 5 frame winding arbor extraction presses are set, the hollow forging behind 8 tandem rollings is deviate to enter next operation-20 frame stretch reducing operation from plug;
(6) configuration 20 frame three-roller tension reducing mill framves after 5 frame winding arbor extraction press groups take off hollow forging behind the pipe and enter 20 frame three-roller tension reducing mill framves and be rolled, and form hot fished pipe; Sizing reduction can reach 35%%, and wall thickness reducing amount can reach 18%%, and lengthening coefficient can reach 4.3, and muzzle velocity can reach 13m/s;
(7) will form fished pipe after the hot fished pipe finishing.
Refinement more: in the described step (1), with heating of pipe blank to 1290 ℃.
Step (1), (4) described heating furnace or reheating furnace comprise inclined-bottom heating furnace, step heating-furnace, rotary heating furnace, tunnel heating furnace, induction heating furnace.
Described heating, its temperature range are 1100 ℃.
Described punch is that vertical cone mill, cone-type piercer machine, Di are given up youngster's punch, pushing piercing machine or press piercing mill.
Described pipe mill is MPM tandem rolling tube machine, PQF three-roller tandem rolling tube machine, roller trio skew rolling pipe machine or push-bench, and wherein hot-rolled temperature is 750 ℃.
Described step finishing comprise blow ash, aligning, excision burr tail, hand inspection, defect detecting test, the water pressure test, spray printing sign, corrosion-inhibiting coating, measure each operation or wherein any practical need the combination operation of operation.
Applicant's statement, the present invention illustrates detailed process equipment of the present invention and technological process by the foregoing description, but the present invention is not limited to above-mentioned detailed process equipment and technological process, does not mean that promptly the present invention must rely on above-mentioned detailed process equipment and technological process could be implemented.The person of ordinary skill in the field should understand, any improvement in the present invention to the interpolation of the equivalence replacement of each raw material of product of the present invention and auxiliary element, the selection of concrete mode etc., all drops within protection scope of the present invention and the open scope.
Claims (7)
1. hot rolled seamless steel tube manufacturing process, it is characterized in that: pipe composition quality percentage is: C 0.25～0.35%, Si 0.1～0.5%, Ni 5.0-8.5%, Zr 3.5-4.8%, Mn 1.0～2.0%, V 0.05～0.25%, N 0.015～0.030%, Fe surplus and inevitable impurity;
Described manufacturing process is:
(1) pipe is heated in heating furnace;
(2) two punches being set bores a hole to the pipe after heating;
(3) 8 frame tandem rolling tube machines are set behind punch, the hollow billet after the perforation is through on the retained mandrel in advance, extend rolling continuously to the hollow billet after boring a hole by 8 frames of continuous layout and the wrong mutually retained mandrel tandem rolling tube machine of roll gap of adjacent breast roller;
(4) hollow billet behind the drilling/rolling is concentrated in the reheating furnace heats again;
(5) behind 8 frame tandem rolling units, 5 frame winding arbor extraction presses are set, the hollow forging behind 8 tandem rollings is deviate to enter next operation-20 frame stretch reducing operation from plug;
(6) configuration 20 frame three-roller tension reducing mill framves after 5 frame winding arbor extraction press groups take off hollow forging behind the pipe and enter 20 frame three-roller tension reducing mill framves and be rolled, and form hot fished pipe; Sizing reduction can reach 35%～42%, and wall thickness reducing amount can reach 18%～24%, and lengthening coefficient can reach 4.3～5.1, and muzzle velocity can reach 13m/s;
(7) will form fished pipe after the hot fished pipe finishing.
2. hot rolled seamless steel tube manufacturing process according to claim 1 is characterized in that, in the described step (1), with heating of pipe blank to 1290～1400 ℃.
3. hot rolled seamless steel tube manufacturing process according to claim 1 and 2, it is characterized in that step (1), (4) described heating furnace or reheating furnace comprise inclined-bottom heating furnace, step heating-furnace, rotary heating furnace, tunnel heating furnace, induction heating furnace.
4. hot rolled seamless steel tube manufacturing process according to claim 3 is characterized in that, described heating, and its temperature range is 1100～1350 ℃.
5. hot rolled seamless steel tube manufacturing process according to claim 1 is characterized in that, described punch is that vertical cone mill, cone-type piercer machine, Di are given up youngster's punch, pushing piercing machine or press piercing mill.
6. hot rolled seamless steel tube manufacturing process according to claim 1 is characterized in that described pipe mill is MPM tandem rolling tube machine, PQF three-roller tandem rolling tube machine, roller trio skew rolling pipe machine or push-bench, and wherein hot-rolled temperature is 750-900 ℃.
7. hot rolled seamless steel tube manufacturing process according to claim 1, it is characterized in that, described step finishing comprise blow ash, aligning, excision burr tail, hand inspection, defect detecting test, the water pressure test, spray printing sign, corrosion-inhibiting coating, measure each operation or wherein any practical need the combination operation of operation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011102444709A CN102284486A (en) | 2011-08-24 | 2011-08-24 | Process for manufacturing seamless steel tubes by hot rolling |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011102444709A CN102284486A (en) | 2011-08-24 | 2011-08-24 | Process for manufacturing seamless steel tubes by hot rolling |
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| CN102284486A true CN102284486A (en) | 2011-12-21 |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102581014A (en) * | 2012-02-07 | 2012-07-18 | 王国亮 | Process for producing thin-wall seamless steel tubes |
| CN102632078A (en) * | 2012-05-03 | 2012-08-15 | 无锡西姆莱斯石油专用管制造有限公司 | Production method of J55 steel-grade oil casing capable of resisting impact load |
| CN102974615A (en) * | 2012-11-08 | 2013-03-20 | 聊城市开发区全运钢管制造有限公司 | Rolling process method of punched lining core of steel rod |
| CN106216400A (en) * | 2016-08-03 | 2016-12-14 | 太原磬泓机电设备有限公司 | The external diameter roll seamless steel tube Processes and apparatus installation system more than 60mm |
| CN110340147A (en) * | 2019-07-12 | 2019-10-18 | 林州凤宝管业有限公司 | A kind of outer small-caliber seamless steel pipe production method through being less than 60mm |
| CN111282997A (en) * | 2020-02-17 | 2020-06-16 | 包头钢铁（集团）有限责任公司 | A production method for 12Cr1MoVG hot continuous rolling of heat-resistant seamless steel pipe |
| CN111845912A (en) * | 2020-06-18 | 2020-10-30 | 浙江久鼎机械有限公司 | Round hot-rolled seamless steel tube for vehicle and preparation process thereof |
| CN112974535A (en) * | 2021-02-04 | 2021-06-18 | 大冶特殊钢有限公司 | Manufacturing method of seamless steel tube for cast tube die |
| CN114700367A (en) * | 2022-06-06 | 2022-07-05 | 邢台军华机械科技有限公司 | Seamless steel pipe hot expanding production system |
| CN116116903A (en) * | 2022-12-28 | 2023-05-16 | 鑫鹏源(聊城)智能科技有限公司 | Titanium alloy hot-rolled seamless pipe production system and production process thereof |
-
2011
- 2011-08-24 CN CN2011102444709A patent/CN102284486A/en active Pending
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102581014A (en) * | 2012-02-07 | 2012-07-18 | 王国亮 | Process for producing thin-wall seamless steel tubes |
| CN102632078A (en) * | 2012-05-03 | 2012-08-15 | 无锡西姆莱斯石油专用管制造有限公司 | Production method of J55 steel-grade oil casing capable of resisting impact load |
| CN102974615A (en) * | 2012-11-08 | 2013-03-20 | 聊城市开发区全运钢管制造有限公司 | Rolling process method of punched lining core of steel rod |
| CN106216400A (en) * | 2016-08-03 | 2016-12-14 | 太原磬泓机电设备有限公司 | The external diameter roll seamless steel tube Processes and apparatus installation system more than 60mm |
| CN110340147A (en) * | 2019-07-12 | 2019-10-18 | 林州凤宝管业有限公司 | A kind of outer small-caliber seamless steel pipe production method through being less than 60mm |
| CN111282997A (en) * | 2020-02-17 | 2020-06-16 | 包头钢铁（集团）有限责任公司 | A production method for 12Cr1MoVG hot continuous rolling of heat-resistant seamless steel pipe |
| CN111845912A (en) * | 2020-06-18 | 2020-10-30 | 浙江久鼎机械有限公司 | Round hot-rolled seamless steel tube for vehicle and preparation process thereof |
| CN111845912B (en) * | 2020-06-18 | 2023-09-01 | 浙江久鼎机械有限公司 | Round hot-rolled seamless steel tube for vehicles and preparation process thereof |
| CN112974535A (en) * | 2021-02-04 | 2021-06-18 | 大冶特殊钢有限公司 | Manufacturing method of seamless steel tube for cast tube die |
| CN114700367A (en) * | 2022-06-06 | 2022-07-05 | 邢台军华机械科技有限公司 | Seamless steel pipe hot expanding production system |
| CN116116903A (en) * | 2022-12-28 | 2023-05-16 | 鑫鹏源(聊城)智能科技有限公司 | Titanium alloy hot-rolled seamless pipe production system and production process thereof |
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Application publication date: 20111221 |