CN102699102A - Production process method of small-caliber cold-drawing seamless steel tube used for boiler - Google Patents
Production process method of small-caliber cold-drawing seamless steel tube used for boiler Download PDFInfo
- Publication number
- CN102699102A CN102699102A CN2012101861600A CN201210186160A CN102699102A CN 102699102 A CN102699102 A CN 102699102A CN 2012101861600 A CN2012101861600 A CN 2012101861600A CN 201210186160 A CN201210186160 A CN 201210186160A CN 102699102 A CN102699102 A CN 102699102A
- Authority
- CN
- China
- Prior art keywords
- tube
- pipe
- cold
- boiler
- steel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Metal Extraction Processes (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention provides a production process method of a small-caliber cold-drawing seamless steel tube used for a boiler. The technological method including the steps of heating with an annular heater, punching by oblique rolling, tube-rolling by an automatic tube rolling mill, reducing a diameter by using a reducing mill through hot-rolling, cold-drawing and performing heat treatment is adopted. As high temperature of a steel tube is utilized to perform diameter reduction process on the steel tube, diameter reduction rate reaches to 25%, number of cycles of the cold-drawing of the steel tube is reduced, cold-drawing amount is respectively reduced by 30-70%, optimal production technology of the steel tube of a high-pressure boiler is created, energy consumption for steel tube production is reduced, and production efficiency is improved. According to the invention, a tube billet is obliquely placed in the annular heating furnace through a mechanical arm to lengthen the heating length, so that an overlong steel tube can be produced by using the lengthened tube billet. Under the condition of short-process production process the performance control method of the cold-drawing seamless steel tube is adopted by the boiler, the technologies such as small flow, multiple nozzles arranged at the side surfaces and the like are adopted by the heat treatment furnace; a computer fuzzy control technology is adopted by the heating furnace and the heat treatment furnace to control atmospheres inside the furnace; and the performances and organization of the produced cold-drawing boiler steel tubes are satisfied with standard requirements.
Description
Technical field
The present invention relates to the manufacturing technique method of a kind of boiler, especially the process of low-cost production ultralong overweight steel pipe with small-bore solid drawn tube.
Background technology
In order to satisfy station boiler to overcritical, ultra supercritical demand for development; Improve the process industrial art performance of boiler with seamless steel pipe, the length that small-bore Boiler Used Coldly pulls out seamless steel pipe develops more than 12m, and the diameter of raw materials for production pipe and length increase; The traditional processing technology method mainly comprises the steps: perforation, plug rolling, cold-drawn and heat treatment; Because the length of fished pipe increases, cause the pipe increasing diameter to cause the cold-drawn passage to increase greatly, therefore the heating of pipe blank length of former firing equipment can not meet the demands; Cold-drawn processing also exists energy consumption high, efficient low with defective such as cost increase.
When some has the boiler of length requirement to use small-caliber steel pipe in production, since the restriction of rolling equipment length, the production that need feed intake with bigger pipe, and, could satisfy the above length requirement of steel pipe 12m through multi-pass cold-drawn processing.Like the steel pipe of specification Φ 51 * 6 * 12000mm, need to use Φ 90mm, the pipe of length 2000mm to feed intake to produce and just can reach 12000mm length, 5 passages of cold-drawn.Under the normal condition, no special length requirement is used Φ 75mm, and length 1500mm pipe feeds intake and produces just passablely, only needs 3 passages of cold-drawn.
Produce with bigger pipe material, will increase the cold-drawn passage, need to increase heat treatment, pickling, operation such as lubricated, supplement production materials such as consumes energy and sulfuric acid, the treating capacity of increase spent acid.In producing the seamless steel tube for boiler production technology in enormous quantities, the size of demand rolled steel tube and cold-drawn finished product is approaching as far as possible, reduces the cold-drawn passage.The main means that adopt are the sizes that reduce the drawn tube material through hot-rolling method.The general pipe production of adopting near finished diameter, and because the mill length restriction, little pipe has satisfied not the requirement of product substance.Therefore, need seek a kind of new process,, not increase the cold-drawn passage again, even can reduce cold-drawn passage, the reduction energy and supplies consumption to increase the length and the substance of product.
Summary of the invention
Above-mentioned deficiency to the prior art existence; Technical problem to be solved by this invention is length and the substance that how to increase product; And reduce the cold-drawn passage as far as possible, reach and reduce production costs, and the manufacturing technique method of a kind of boiler with small-bore solid drawn tube is provided.
Solve the technical problem, the technical scheme that the present invention adopts is: boiler is characterized in that with the manufacturing technique method of small-bore solid drawn tube, comprises following processing step:
Roll piercing: heating of pipe blank to 1180-1220 ℃, is delivered to pipe in the graceful formula punch and bores a hole;
The automatic tube rolling mill tube rolling: perforation back steel pipe pulls out to automatic tube rolling mill and carries out tube rolling by pulling out the steel machine;
Reducing mill hot rolling tube reducing: the temperature of steel is pulled out to the mini-stretch reducing mill tube reducing by pulling out the steel machine at 840 ℃～900 ℃ behind the tube rolling, and sizing reduction is controlled at 22%～25%;
Cold-drawn:, send to heat treatment after the cold-drawn with the cold-drawn of chain type drawbench;
Heat treatment: temperature controlling range: 600～1050 ℃, Control for Kiln Temperature precision ± 5 ℃, the time is 20-120 minute.
Further, the concrete steps of process of the present invention comprise:
1) removes blemish with the emery wheel reconditioning after the pipe pickling, and be cut into the length that needs;
2) with rollgang pipe is delivered to rotary heating furnace charging manipulator, manipulator is clamped pipe and is sent in the stove, is rotated into radial line to be 35 ° of angles; After being heated to 1180-1220 ℃, changing into radial line by discharging machinery hand-screw and to be 35 ° of angles, clamp pipe after, 35 ° of derotations are return pipe are placed rollgang, pipe is delivered in the graceful formula punch and carries out roll piercing;
3) pull out to automatic tube rolling mill and carry out tube rolling by pulling out the steel machine;
4) temperature of steel is pulled out to the mini-stretch reducing mill tube reducing sizing reduction 25% by pulling out the steel machine behind the tube rolling about 840-900 ℃;
5) treat to carry out pickling and lubricated with sulfuric acid after the steel pipe cooling, use the cold-drawn of chain type drawbench again;
6) fished pipe send heat-treatment furnace to heat-treat, temperature controlling range: 600～1050 ℃, and Control for Kiln Temperature precision ± 5 ℃, the time is 20-120 minute.
7) reach the steel pipe of performance requirement after the heat treatment, send to align, the Pipe Cutting finishing.
Compare prior art, the short flow process of the present invention is produced the manufacturing technique method of boiler with small-bore solid drawn tube, has following beneficial effect:
1, adopts hot-working roll piercing+automatic tube rolling mill tube rolling+reducing mill hot rolling tube reducing+cold-drawn+heat-treatment technology method, utilize the high temperature of steel pipe, steel pipe is carried out the processing of hot rolling tube reducing; Reducing rate reaches 25%; Reduce the cycle-index of steel pipe cold-drawn, reduce cold-drawn amount 30～70% respectively, created the optimum production process of high-pressure boiler steel pipe; Reduce the steel pipe's production energy resource consumption, improved production efficiency.
2, the present invention is tiltedly put pipe through manipulator in rotary heating furnace, increases heated length, realizes with the pipe production overlength steel pipe behind the lengthening.
3, under the productive technology of short flow condition; Boiler Used Coldly pulls out the Properties Control method of seamless steel pipe; Heat-treatment furnace adopts low discharge; Technology such as many burners side arrangement, heating furnace and heat-treatment furnace are with computer fuzzy control technology control furnace atmosphere, and the performance of the cold-drawn seamless steel tube for boiler of production, tissue satisfy standard-required.
The present invention especially is fit to the steel pipe that low-cost production length and substance all have requirement.
Description of drawings
Fig. 1 is the manufacturing technique method flow chart of boiler of the present invention with small-bore solid drawn tube.
The specific embodiment
Below in conjunction with specific embodiment the present invention is done further explain.
A kind of boiler is with the manufacturing technique method of small-bore solid drawn tube, and concrete steps are:
Remove blemish with the emery wheel reconditioning after the pipe pickling; The pipe that reconditioning is good winches to the length that bar shears is cut into to be needed with crane; With rollgang pipe is delivered to rotary heating furnace charging manipulator, manipulator is clamped pipe and is sent in the stove, is rotated into radial line to be 35 ° of angles; Place pipe, increase heated length.Heating of pipe blank is changed into radial line by discharging machinery hand-screw and to be 35 ° of angles after 1180-1220 ℃, clamp pipe after, 35 ° of derotations are return pipe are placed rollgang.Pipe is delivered in the graceful formula punch and bores a hole.Perforation back steel pipe pulls out to automatic tube rolling mill and carries out tube rolling by pulling out the steel machine, and the temperature of steel is pulled out to the mini-stretch reducing mill tube reducing by pulling out the steel machine about 850 ℃ behind the tube rolling; Sizing reduction 25%, the steel pipe behind the tube reducing is taken the lead with the hydraulic pressure heading machine, and the back of taking the lead is collected and is stacked; Treat to deliver to pickling tube after the steel pipe cooling, carry out pickling with sulfuric acid; Remove the iron scale of steel pipe, inspection steel tube surface situation carries out removing with abrasive machine to defective.Steel pipe after the removal of defects is delivered to pickling in the pickling tube again, lubricated after the pickling, and the steel pipe after lubricating is delivered to cold-drawn, with the cold-drawn of chain type drawbench, sends to heat treatment after the cold-drawn.The steel pipe that need carry out cold-drawn again carries out pickling again and lubricates; Arrive cold-drawn again, fished pipe send heat-treatment furnace to heat-treat, and heat-treatment furnace adopts many burners, low discharge, side arrangement technology; The fuzzy control technology of computer is adopted in temperature control; Temperature controlling range: 600～1050 ℃, Control for Kiln Temperature precision ± 5 ℃, the time is 20-120 minute.Heat treatment comprises 800～1050 ℃ of normalized treatment, and the time is 20-25 minute; 600～750 ℃ of temper, the time is 1.5～2 hours.Different according to rolling shapes and wall thickness are selected the proper heat treatment mode, need normalized treatment behind aligning, to carry out temper again like steel alloy, then only need normalized treatment to get final product for low-carbon (LC) tubing.
Reach the steel pipe of performance requirement after the heat treatment, send at last align, the Pipe Cutting finishing.The laggard pedestrian worker's check of steel pipe finishing, nondestructive inspection, qualified steel pipe is packed warehouse-in.
Explanation is at last; Above embodiment is only unrestricted in order to technical scheme of the present invention to be described; Although with reference to preferred embodiment the present invention is specified, those of ordinary skill in the art should be appreciated that and can make amendment or be equal to replacement technical scheme of the present invention; And not breaking away from the aim and the scope of technical scheme of the present invention, it all should be encompassed in the middle of the claim scope of the present invention.
Claims (3)
1. boiler is characterized in that with the manufacturing technique method of small-bore solid drawn tube, comprises following processing step:
Roll piercing:, pipe is delivered in the graceful formula punch bores a hole again with heating of pipe blank to 1180～1220 ℃;
The automatic tube rolling mill tube rolling: perforation back steel pipe pulls out to automatic tube rolling mill and carries out tube rolling by pulling out the steel machine;
Reducing mill hot rolling tube reducing: the temperature of steel is pulled out to the mini-stretch reducing mill tube reducing by pulling out the steel machine at 840 ℃～900 ℃ behind the tube rolling, and sizing reduction is controlled at 22%～25%;
Cold-drawn:, send to heat treatment after the cold-drawn with the cold-drawn of chain type drawbench;
Heat treatment: temperature controlling range: 650～1050 ℃, Control for Kiln Temperature precision ± 5 ℃, the time is 20-120 minute.
2. according to the manufacturing technique method of the said boiler of claim 1, it is characterized in that concrete steps comprise with small-bore solid drawn tube:
1) removes blemish with the emery wheel reconditioning after the pipe pickling, and be cut into the length that needs;
2) with rollgang pipe is delivered to rotary heating furnace charging manipulator, manipulator is clamped pipe and is sent in the stove, is rotated into radial line to be 35 ° of angles; After being heated to 1180～1220 ℃, changing into radial line by discharging machinery hand-screw and to be 35 ° of angles, clamp pipe after, 35 ° of derotations are return pipe are placed rollgang, pipe is delivered in the graceful formula punch and carries out roll piercing;
3) pull out to automatic tube rolling mill and carry out tube rolling by pulling out the steel machine;
4) temperature of steel is pulled out to the mini-stretch reducing mill tube reducing sizing reduction 25% by pulling out the steel machine behind the tube rolling about 840 ℃-900 ℃;
5) treat to carry out pickling and lubricated with sulfuric acid after the steel pipe cooling, use the cold-drawn of chain type drawbench again;
6) fished pipe send heat-treatment furnace to heat-treat, temperature controlling range: 600～1050 ℃, and Control for Kiln Temperature precision ± 5 ℃, the time is 20-120 minute;
7) reach the steel pipe of performance requirement after the heat treatment, send to align, the Pipe Cutting finishing.
3. according to the manufacturing technique method of the said boiler of claim 1 with small-bore solid drawn tube, it is characterized in that said heat treatment comprises 800～1050 ℃ of normalized treatment, the time is 20-25 minute; 600～750 ℃ of temper, the time is 1.5～2 hours.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210186160.0A CN102699102B (en) | 2012-06-07 | 2012-06-07 | Production process method of small-caliber cold-drawing seamless steel tube used for boiler |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210186160.0A CN102699102B (en) | 2012-06-07 | 2012-06-07 | Production process method of small-caliber cold-drawing seamless steel tube used for boiler |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102699102A true CN102699102A (en) | 2012-10-03 |
| CN102699102B CN102699102B (en) | 2015-06-03 |
Family
ID=46892320
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210186160.0A Expired - Fee Related CN102699102B (en) | 2012-06-07 | 2012-06-07 | Production process method of small-caliber cold-drawing seamless steel tube used for boiler |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102699102B (en) |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102921763A (en) * | 2012-12-05 | 2013-02-13 | 天津市大地工贸有限公司 | Seamless steel tube processing technology |
| CN102921752A (en) * | 2012-11-15 | 2013-02-13 | 河海大学常州校区 | Hydraulic pressure cold-drawing production technique of metal pipe, and complete device of hydraulic pressure cold-drawing production technique |
| CN102962290A (en) * | 2012-11-21 | 2013-03-13 | 嘉兴市新纪元钢管制造有限公司 | High-efficiency production process capable of improving surface accuracy of cold-drawn seamless steel tube |
| CN103272877A (en) * | 2013-05-23 | 2013-09-04 | 苏州贝思特金属制品有限公司 | Low-carbon inconel seamless tube |
| CN103921066A (en) * | 2014-03-18 | 2014-07-16 | 泰州双羊精密无缝钢管有限公司 | Method for manufacturing seamless steel pipes for shock absorbers |
| CN103921065A (en) * | 2014-03-18 | 2014-07-16 | 泰州双羊精密无缝钢管有限公司 | Manufacturing method of vehicle seamless steel tubes |
| CN104174688A (en) * | 2014-07-21 | 2014-12-03 | 苏州贝思特金属制品有限公司 | Production process of seamless stainless steel tube |
| CN104307876A (en) * | 2014-10-20 | 2015-01-28 | 张家港市人和高精管有限公司 | Production process of precise seamless steel tube for hydraulic cylinder |
| CN104815845A (en) * | 2015-05-28 | 2015-08-05 | 攀钢集团成都钢钒有限公司 | Machining method of steel pipe |
| CN104907352A (en) * | 2015-05-20 | 2015-09-16 | 湖州华特不锈钢管制造有限公司 | Condenser stainless steel pipe production method |
| CN107685088A (en) * | 2017-09-30 | 2018-02-13 | 徐州翔凯重工科技有限公司 | A kind of preparation method of drawn tube |
| CN111468557A (en) * | 2020-04-29 | 2020-07-31 | 浙江新航不锈钢有限公司 | Cold-drawing production line and production process for stainless steel seamless tube |
| CN111495984A (en) * | 2020-05-10 | 2020-08-07 | 江苏联峰实业有限公司 | Production method of reducing round bar rolled steel |
| CN112605150A (en) * | 2020-11-26 | 2021-04-06 | 衡阳鸿常机化有限公司 | Low-cost seamless steel tube manufacturing method |
| CN113477857A (en) * | 2021-04-06 | 2021-10-08 | 江苏太平洋精锻科技股份有限公司 | Forming processing method of hollow motor shaft |
| CN113546979A (en) * | 2021-07-22 | 2021-10-26 | 良启金属南通有限公司 | Preparation process of high-strength metal bar |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1113458A (en) * | 1994-12-23 | 1995-12-20 | 宝山钢铁(集团)公司 | Production process for hot-rolled boiler pipe of 12Cr2MoWVTiB steel alloy |
| CN101440428A (en) * | 2008-12-19 | 2009-05-27 | 常州市新亚不锈钢管有限公司 | Production method of seamless stainless steel tube for high-pressure boiler |
| CN101954377A (en) * | 2010-09-13 | 2011-01-26 | 胡顺珍 | Full-floating mandrel tandem-rolling seamless steel pipe production process |
| CN102319764A (en) * | 2011-07-18 | 2012-01-18 | 新兴铸管股份有限公司 | Method for manufacturing stainless steel seamless tube |
| CN102363256A (en) * | 2011-06-16 | 2012-02-29 | 深圳市北科航飞生物医学工程有限公司 | A method of processing cobalt-base alloy superfine thin-walled tubes for stents |
-
2012
- 2012-06-07 CN CN201210186160.0A patent/CN102699102B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1113458A (en) * | 1994-12-23 | 1995-12-20 | 宝山钢铁(集团)公司 | Production process for hot-rolled boiler pipe of 12Cr2MoWVTiB steel alloy |
| CN101440428A (en) * | 2008-12-19 | 2009-05-27 | 常州市新亚不锈钢管有限公司 | Production method of seamless stainless steel tube for high-pressure boiler |
| CN101954377A (en) * | 2010-09-13 | 2011-01-26 | 胡顺珍 | Full-floating mandrel tandem-rolling seamless steel pipe production process |
| CN102363256A (en) * | 2011-06-16 | 2012-02-29 | 深圳市北科航飞生物医学工程有限公司 | A method of processing cobalt-base alloy superfine thin-walled tubes for stents |
| CN102319764A (en) * | 2011-07-18 | 2012-01-18 | 新兴铸管股份有限公司 | Method for manufacturing stainless steel seamless tube |
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102921752A (en) * | 2012-11-15 | 2013-02-13 | 河海大学常州校区 | Hydraulic pressure cold-drawing production technique of metal pipe, and complete device of hydraulic pressure cold-drawing production technique |
| CN102962290B (en) * | 2012-11-21 | 2016-06-15 | 浙江新纪元管业科技有限公司 | Improve the production technology of solid drawn tube surface accuracy |
| CN102962290A (en) * | 2012-11-21 | 2013-03-13 | 嘉兴市新纪元钢管制造有限公司 | High-efficiency production process capable of improving surface accuracy of cold-drawn seamless steel tube |
| CN102921763A (en) * | 2012-12-05 | 2013-02-13 | 天津市大地工贸有限公司 | Seamless steel tube processing technology |
| CN103272877A (en) * | 2013-05-23 | 2013-09-04 | 苏州贝思特金属制品有限公司 | Low-carbon inconel seamless tube |
| CN103921066A (en) * | 2014-03-18 | 2014-07-16 | 泰州双羊精密无缝钢管有限公司 | Method for manufacturing seamless steel pipes for shock absorbers |
| CN103921065A (en) * | 2014-03-18 | 2014-07-16 | 泰州双羊精密无缝钢管有限公司 | Manufacturing method of vehicle seamless steel tubes |
| CN104174688A (en) * | 2014-07-21 | 2014-12-03 | 苏州贝思特金属制品有限公司 | Production process of seamless stainless steel tube |
| CN104307876A (en) * | 2014-10-20 | 2015-01-28 | 张家港市人和高精管有限公司 | Production process of precise seamless steel tube for hydraulic cylinder |
| CN104907352A (en) * | 2015-05-20 | 2015-09-16 | 湖州华特不锈钢管制造有限公司 | Condenser stainless steel pipe production method |
| CN104815845A (en) * | 2015-05-28 | 2015-08-05 | 攀钢集团成都钢钒有限公司 | Machining method of steel pipe |
| CN107685088A (en) * | 2017-09-30 | 2018-02-13 | 徐州翔凯重工科技有限公司 | A kind of preparation method of drawn tube |
| CN111468557A (en) * | 2020-04-29 | 2020-07-31 | 浙江新航不锈钢有限公司 | Cold-drawing production line and production process for stainless steel seamless tube |
| CN111495984A (en) * | 2020-05-10 | 2020-08-07 | 江苏联峰实业有限公司 | Production method of reducing round bar rolled steel |
| CN112605150A (en) * | 2020-11-26 | 2021-04-06 | 衡阳鸿常机化有限公司 | Low-cost seamless steel tube manufacturing method |
| CN113477857A (en) * | 2021-04-06 | 2021-10-08 | 江苏太平洋精锻科技股份有限公司 | Forming processing method of hollow motor shaft |
| CN113477857B (en) * | 2021-04-06 | 2022-11-08 | 江苏太平洋精锻科技股份有限公司 | Forming processing method of hollow motor shaft |
| CN113546979A (en) * | 2021-07-22 | 2021-10-26 | 良启金属南通有限公司 | Preparation process of high-strength metal bar |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102699102B (en) | 2015-06-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102699102B (en) | Production process method of small-caliber cold-drawing seamless steel tube used for boiler | |
| CN104759850B (en) | A kind of aluminium alloy height barrier part processing technique | |
| CN104259199B (en) | Stainless steel wire rod rolling mill practice | |
| CN103480647B (en) | A kind of device and production method thereof of producing reinforcing bar without heating low temperature Direct Rolling small billet | |
| CN104439933B (en) | Technological method for improving performance of large-diameter carbon steel cast and rolled flange part | |
| RU2523398C1 (en) | PRODUCTION OF SEAMLESS COLD-FORMED OIL-WELL TUBING SIZED TO 114,3×6, 8×9000-10700 mm FROM CORROSION-RESISTANT ALLOY OF "ХН30МДБ-Ш" GRADE | |
| KR20010022646A (en) | Method for producing steel rolling bearing rings | |
| RU2527578C2 (en) | PRODUCTION OF SEAMLESS COLD-FORMED OIL-WELL TUBING SIZED TO 88,9×6,45×9000-10700 mm FROM CORROSION-RESISTANT ALLOY OF "ХН30МДБ-Ш" GRADE | |
| CN111589871A (en) | Production line and production process of small-caliber thick-wall seamless steel pipe | |
| CN102632175A (en) | Radial forging process of cast-state magnesium alloy tube | |
| CN106180195B (en) | 508 millimeters of heavy caliber seamless steel pipe hot continuous rolling process | |
| CN110899335A (en) | Short-process manufacturing method of small-caliber marine titanium alloy seamless pipe | |
| CN102615138A (en) | Method for manufacturing titanium pipe | |
| CN104399745A (en) | Steekle mill production line provided with roughing mill and work method of steekle mill production line | |
| JP4672022B2 (en) | Equipment for producing metal products by rolling | |
| CN104399748B (en) | A kind of production technology that can replace conventional broadband steel hot continuous rolling | |
| CN104438333A (en) | Tri-roller reciprocating type skew rolling technique of seamless pipes | |
| CN105290281B (en) | The production method of the nickeliferous ring forging of large thick-wall | |
| CN101862949A (en) | Backward extrusion forging method | |
| CN110340147A (en) | A kind of outer small-caliber seamless steel pipe production method through being less than 60mm | |
| CN102703838B (en) | Production process for PSL-2 grade non-tempered N80 steel grade oil casing pipes | |
| CN212442565U (en) | Production line of small-caliber thick-wall seamless steel pipe | |
| CN101468360B (en) | Seamless oil well steel tube restraint tandem rolling processing equipment | |
| CN106269857A (en) | The production technology that carbon steel is coiled | |
| CN102974615A (en) | Rolling process method of punched lining core of steel rod |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20150603 Termination date: 20210607 |