CN1544168A - Hollow drill steel rolling process - Google Patents
Hollow drill steel rolling process Download PDFInfo
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- CN1544168A CN1544168A CNA2003101114406A CN200310111440A CN1544168A CN 1544168 A CN1544168 A CN 1544168A CN A2003101114406 A CNA2003101114406 A CN A2003101114406A CN 200310111440 A CN200310111440 A CN 200310111440A CN 1544168 A CN1544168 A CN 1544168A
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- rolling
- roller
- soaking
- induction heating
- axial rolling
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Abstract
The invention relates to a hollow drill steel rolling technique, including the working procedures of medium frequency induction heating, perforating by two roller inclined rolling, reducing diameter by three roller-core inclined rolling, fixing diameter and molding by three-roller vertical rolling, and controlling and cooling, and its character: behind working procedure of the medium frequency induction heating, there is an industrial frequency soaking working procedure and the adopted device is an industrial frequency soaking furnace. It adds industrial frequency soaking working procedure to the steel rolling technique, ensuring the inner gold phase tissue of finished product is uniform; it improves hollow drill steel gold-phase tissue and eliminates the inner-surface thread of the central hole and the roll defect, prolongs the service life of the drill steel.
Description
Technical field
The invention belongs to the steel field, particularly the rolling mill practice of hollow steel.
Background technology
The steel rolling quality is rolling quality the having the greatest impact to fatigue limit of the outer surface and the endoporus of one of key factor that influences the steel life-span, particularly steel.
At present, be representative abroad with Sweden Sandvik company, employing be " steel billet boring belt carcass hot rolling method ", be called for short " boring method ".This method is pulled out skin with the refining steel round blank, after drilling through the hole, insert the potassium steel plug, then with fuel oil or combustion gas heating, on many short stress path rolling mills of special use, roll into hexagonal or the circular hollow steel of inscribed circle diameter φ 19～φ 51mm through 19～21 passages, its production process and technological process are: 50 tons of electric furnaces just refine, the ladle external refining, the vacuum drying oven degassing, continuous casting square billet, (circle base size: φ 122 * 1340 for split rolling method, φ 132 * 1380, φ 146 * 1340mm), the circle base strips off the skin, the circle base bores central through hole, dress potassium steel core, the oil gas heating, reversing two-high mill roughing (9 passage), three-high mill intermediate rolling, the finish rolling of seven short stress milling trains of flat edger roll is become a useful person, online detection, the cold bed control is cold, haircut is loosed core, alignment, sizing, finishing, inspection eventually, the packing warehouse-in.This method technical maturity, the circle base pulls out skin, boring makes the stock steel better, and multi-pass does not have the tension force axial rolling, makes become a useful person tissue and stress state good, product geometric accuracy height, the surfaces externally and internally quality is good.Add its experience accumulation,, do not run into big challenge so far so the finished product quality in kind of its whole pricker, drill steel occupy world lead level for a long time at steel grade, smelting and system pricker process aspect.But Just because of this, its ceternally immutable technological process also has weak point: 1. this method complex process, exigent managerial skills; 2. naked light heating has adverse effect to steel and environment; 3. modern technologies improve steel and nonessential pull out skin, boring can not, adopt boring, pull out skin technology and make the steel lumber recovery reduce about 12～15%; 4. need to be equipped with a large amount of boring, pull out the skin special equipment, φ 30～φ 48mm spray-sucking type drill bit consumption of holing used is very big (only can hole 18～25m) for every; 5. need to increase the smelting roll process and the equipment of potassium steel cores such as preparation and recovery 80Mn14; 6. needing increases technology and the equipment of loosing core, and has further reduced the lumber recovery of steel again.Therefore, this explained hereafter long flow path, equipment investment is many, and the steel waste is big, and the product cost height also has certain environmental pollution.
In view of above factor, at the beginning of 90, domestic by the each side expert according to China national conditions and enterprise's existence conditions at that time, a kind of hollow steel production new technique of succeeding in developing in 1993: " heat is worn-the hot rolling method "." heat is worn-the hot rolling method " main production process of hollow steel: charging, Frequency Induction Heating, Mannesmann piercing, roller trio skew rolling tube reducing, six roller axial rolling moulding, cold bed control cooling, finished product discharging.The advantage of " heat is worn-the hot rolling method " is to have adopted electrical heating, an axial rolling of no tension force is become a useful person behind the tube reducing, need not prepare core and loose core, centre bore is relatively round just, and the lumber recovery height can be produced φ 19～φ 51mm complete series steel product, and reduced investment, product cost is low, non-environmental-pollution, automaticity height.One of shortcoming of this method be blank after heating in medium frequency, internal-external temperature difference is bigger, the finished product inside metallographic after rolling is inhomogeneous; Two of shortcoming is that blank is after the Mannesmann piercing operation, in the hollow oblique milling tube reducing of three rollers, the hollow axial rolling molding procedure of six rollers, blank is forced to stretch and reverse down distortion, central hole size can not get control (mandrelless rolling), can produce darker spiral lamination and fold, the antifatigue stress defective of having aggravated the centre bore inner surface, the hollow steel quality problems of being produced are still more outstanding, service life is shorter, still has big gap apart from international most advanced level.
Domesticly done some useful explorations, its main points are to have increased the plug that centre bore is play supporting role in three roller tube reducing operations to be rolled for this reason.In the operation of rolling, because the effect of frictional force between plug and centre bore inner surface, centre bore has limited reversing of inner surface metal under the effect of radial pressure and frictional force, defectives such as helix that perforation process produces and burr have partly been removed, improve the metallographic structure of hollow steel, improved the centre bore inner surface quality.Its production technology is: the heating of blank naked light, Mannesmann piercing, three roller strap core oblique milling tube reducings, dog, six roller hot drawing moulding.The shortcoming of this rolling mill practice is: 1. the naked light heating has environmental pollution, and heat time heating time is longer, and automaticity is lower, the difficult control of blank oxidation and decarbonization; 2. hot drawing molding procedure still is a mandrelless rolling, and at the tension state compacted under, the metallographic structure of finished product steel material, central hole size, inner surface spiral lamination still can not get better control, and the life-span does not reach perfect condition; 3. the hot drawing moulding process has reduced the lumber recovery of steel because of dog, and the production of major diameter and the heavy steel of overlength is restricted.
In sum, causing short main cause of present steel life-span is the technologic problem of Rolling Production: the one, and round steel blank heating internal-external temperature difference is bigger, and the 2nd, tube reducing and molding procedure center hole shape and inner surface quality can't guarantee.
Summary of the invention
Purpose of the present invention just provides a kind ofly can accurately control the round steel blank temperature, reduce the blank internal-external temperature difference, improve the metallographic structure of hollow steel stocking, eliminate the hollow steel rolling mill practice of centre bore inner surface spiral lamination.
For reaching this purpose, inventive concept of the present invention is after round steel blank heating process, and increase can be controlled blank temperature, reduce the power frequency soaking operation of blank internal-external temperature difference before the perforation process, guarantees that the hollow steel finished product inside metallographic after rolling is even.
Rolling circular hollow steel is behind perforation process, in roller trio skew rolling tube reducing and three roller axial rolling sizing molding procedure, all adopts centre bore cored bar rolling mill practice (that is: " perforation-omnidistance belt carcass steel rolling mill practice ").Rolling regular polygon hollow steel is behind perforation process, in roller trio skew rolling tube reducing and multiple roll axial rolling molding procedure, all adopts centre bore cored bar rolling mill practice (that is: " perforation-omnidistance belt carcass steel rolling mill practice ").This has just improved the metallographic structure of hollow steel stocking, has eliminated centre bore inner surface spiral lamination and other rolling defect, has prolonged the service life of steel.
For realizing purpose of the present invention, technical scheme of the present invention is to increase power frequency soaking operation before perforation process, guarantee the blank internal-external temperature difference be controlled at ± 30 ℃ in, its rolling mill practice is: charging, Frequency Induction Heating, power frequency soaking, Mannesmann piercing, three roller strap core oblique milling tube reducings, three roller axial rolling sizing moulding, control cooling, finished product discharging, the employed equipment of power frequency soaking operation is the power frequency soaking pit.Because this technology added power frequency soaking operation, guaranteed that the hollow steel finished product inside metallographic after rolling is even, thereby improved the fatigue limit of hollow steel, prolonged service life.This technology is used for rolling circular hollow steel.
What the application of hollow steel was more is regular polygon hollow steel.The technology of rolling regular polygon hollow steel is: charging, Frequency Induction Heating, power frequency soaking, Mannesmann piercing, three roller strap core oblique milling tube reducings, multiple roll axial rolling moulding, control cooling, finished product discharging; Multiple roll axial rolling moulding refers to: six roller axial rolling moulding, seven roller axial rolling moulding, eight roller axial rolling moulding, nine roller axial rolling moulding; Employed equipment is respectively: six roller axial rolling make-up machines, seven roller axial rolling make-up machines, eight roller axial rolling make-up machines, nine roller axial rolling make-up machines, its axial rolling machine are evenly arranged roll respectively, are respectively six rollers or seven rollers or eight rollers or nine rollers.Regular polygon refers to: regular hexagon, positive heptagon, octagon, positive nonagon; Wherein: regular hexagon is present widely used hollow steel, and we have applied for utility model patent (application number: 03254996.2) positive heptagon, octagon, positive nonagon hollow steel.This technology is used for rolling regular hexagon, positive heptagon, octagon, positive nonagon hollow steel.
Improvement project
When rolling hollow steel, adopt " perforation-omnidistance belt carcass steel rolling mill practice ".
For the omnidistance belt carcass of circular hollow steel promptly: tube reducing operation, sizing operation all are with round mandrel rolling.Its rolling mill practice is: charging, Frequency Induction Heating, power frequency soaking, Mannesmann piercing, three roller strap core oblique milling tube reducings, three roller strap core axial rolling sizing moulding, control cooling, finished product discharging.Tube reducing operation, sizing molding procedure all are with round mandrel rolling (the diameter of mandrel size according to different size, is determined according to hollow steel standard).This technology is used for rolling circular hollow steel.
Refer to for the omnidistance belt carcass of regular polygon hollow steel: tube reducing operation, axial rolling molding procedure all are with round mandrel rolling.Its rolling mill practice is: charging, Frequency Induction Heating, power frequency soaking, Mannesmann piercing, three roller strap core oblique milling tube reducings, multiple roll belt carcass axial rolling moulding, control cooling, finished product discharging; Wherein multiple roll axial rolling moulding refers to: six roller axial rolling moulding, seven roller axial rolling moulding, eight roller axial rolling moulding, nine roller axial rolling moulding; Employed equipment is respectively: six roller axial rolling make-up machines, seven roller axial rolling make-up machines, eight roller axial rolling make-up machines, nine roller axial rolling make-up machines, its axial rolling machine are evenly arranged roll respectively, are respectively six rollers or seven rollers or eight rollers or nine rollers.Tube reducing operation, axial rolling molding procedure all are with round mandrel rolling (the diameter of mandrel size according to different size, is determined according to hollow steel standard).This technology is used for rolling regular hexagon, positive heptagon, octagon, positive nonagon hollow steel.
Owing to adopted " perforation-omnidistance belt carcass steel rolling mill practice ", axiality, cylindricity and the surface roughness requirement of hollow steel centre bore have been guaranteed, improved the metallographic structure of hollow steel stocking, eliminate centre bore inner surface spiral lamination and other rolling defect, reached the further raising hollow steel purpose in service life.
Advantage and good effect
The present invention has added the soaking operation after the heating process in steel rolling process, guarantee that the hollow steel finished product inside metallographic after rolling is even; In tube reducing and axial rolling molding procedure, all adopt centre bore cored bar rolling mill practice, improved the metallographic structure of hollow steel stocking, eliminated centre bore inner surface spiral lamination and other rolling defect, prolonged the service life of hollow steel.The present invention is used for rolling circle, regular hexagon, positive heptagon, octagon, positive nonagon hollow steel.
The specific embodiment
Embodiment one
Band is by the circular hollow steel rolling mill practice flow process and the equipment of power frequency soaking operation:
| Operation | Equipment | |
| ????1 | Charging | |
| ????2 | Frequency Induction Heating (1150～1180 ℃) | Medium Frequency Induction Heating Furnace |
| ????3 | Power frequency soaking (internal-external temperature difference ± 30 ℃) | Multistation power frequency soaking pit |
| ????4 | Mannesmann piercing | The two-roller skew-rolling machine |
| ????5 | Three roller strap core oblique milling tube reducings | Three-roll cross rolling mill |
| ????6 | Three roller axial rolling sizing moulding | Three roller axial rolling sizing mills |
| ????7 | (temperature after rolling＞850 ℃) control cooling | Cold bed |
| ????8 | The finished product discharging | |
Embodiment two
Band is by omnidistance belt carcass rolling mill practice flow process of the circular hollow steel of power frequency soaking operation and equipment:
| Operation | Equipment | |
| ????1 | Charging | |
| ????2 | Frequency Induction Heating (1150～1180 ℃) | Medium Frequency Induction Heating Furnace |
| ????3 | Power frequency soaking (internal-external temperature difference ± 30 ℃) | Multistation power frequency soaking pit |
| ????4 | Mannesmann piercing | The two-roller skew-rolling machine |
| ????5 | Three roller strap core oblique milling tube reducings | Three-roll cross rolling mill |
| ????6 | Three roller strap core axial rolling sizing moulding | Three roller axial rolling sizing mills |
| ????7 | (temperature after rolling＞850 ℃) control cooling | Cold bed |
| ????8 | The finished product discharging |
Embodiment three
Band is by the regular hexagon hollow steel rolling mill practice flow process and the equipment of power frequency soaking operation:
| Operation | Equipment | |
| ????1 | Charging | |
| ????2 | Frequency Induction Heating (1150～1180 ℃) | Medium Frequency Induction Heating Furnace |
| ????3 | Power frequency soaking (internal-external temperature difference ± 30 ℃) | Multistation power frequency soaking pit |
| ????4 | Mannesmann piercing | The two-roller skew-rolling machine |
| ????5 | Three roller strap core oblique milling tube reducings | Three-roll cross rolling mill |
| ????6 | Six roller axial rolling moulding | Six roller axial rolling make-up machines |
| ????7 | (temperature after rolling＞850 ℃) control cooling | Cold bed |
| ????8 | The finished product discharging | |
Embodiment four
Band is by the positive heptagon of power frequency soaking operation, octagon, positive nonagon hollow steel rolling mill practice flow process and equipment:
| Operation | Equipment | |
| ????1 | Charging | |
| ????2 | Frequency Induction Heating (1150～1180 ℃) | Medium Frequency Induction Heating Furnace |
| ????3 | Power frequency soaking (internal-external temperature difference ± 30 ℃) | Multistation power frequency soaking pit |
| ????4 | Mannesmann piercing | The two-roller skew-rolling machine |
| ????5 | Three roller strap core oblique milling tube reducings | Three-roll cross rolling mill |
| ????6 | Seven rollers or eight rollers or nine roller axial rolling moulding | Seven rollers or eight rollers or nine roller axial rolling make-up machines |
| ????7 | (temperature after rolling＞850 ℃) control cooling | Cold bed |
| ????8 | The finished product discharging |
Embodiment five
Band is by the regular hexagon of power frequency soaking operation, positive heptagon, octagon, the omnidistance belt carcass rolling hollow steel technological process of positive nonagon and equipment:
| Operation | Equipment | |
| ????1 | Charging | |
| ????2 | Frequency Induction Heating (1150～1180 ℃) | Medium Frequency Induction Heating Furnace |
| ????3 | Power frequency soaking (internal-external temperature difference ± 30 ℃) | Multistation power frequency soaking pit |
| ????4 | Mannesmann piercing | The two-roller skew-rolling machine |
| ????5 | Three roller strap core oblique milling tube reducings | Three-roll cross rolling mill |
| ????6 | Six rollers or seven rollers or eight rollers or nine roller strap core axial rolling moulding | Six rollers or seven rollers or eight rollers or nine roller axial rolling make-up machines |
| ????7 | (temperature after rolling＞850 ℃) control cooling | Cold bed |
| ????8 | The finished product discharging | |
Claims (5)
1. hollow steel rolling mill practice, its operation has the Frequency Induction Heating operation, the Mannesmann piercing operation, three roller strap core oblique milling tube reducing operations, three roller axial rolling sizing molding procedure, the control refrigerating work procedure is characterized in that: also have power frequency soaking operation after the Frequency Induction Heating operation, the equipment that is adopted is the power frequency soaking pit.
2. by the described hollow steel of claim 1 rolling mill practice, it is characterized in that: three roller axial rolling sizing molding procedure bands circle mandrel rolling.
3. hollow steel rolling mill practice, its operation has the Frequency Induction Heating operation, the Mannesmann piercing operation, three roller strap core oblique milling tube reducing operations, six roller axial rolling molding procedure, the control refrigerating work procedure is characterized in that: also have power frequency soaking operation after the Frequency Induction Heating operation, the equipment that is adopted is the power frequency soaking pit.
4. hollow steel rolling mill practice, its operation has the Frequency Induction Heating operation, the Mannesmann piercing operation, three roller strap core oblique milling tube reducing operations, the control refrigerating work procedure, it is characterized in that: after the Frequency Induction Heating operation, also have power frequency soaking operation, the equipment that is adopted is the power frequency soaking pit, after three roller strap core oblique milling tube reducing operations, also have seven roller axial rolling molding procedure or eight roller axial rolling molding procedure or nine roller axial rolling molding procedure, its axial rolling machine is evenly arranged roll respectively, and the roll number is seven rollers or eight rollers or nine rollers.
5. by claim 3 or the described hollow steel of claim 4 rolling mill practice, it is characterized in that: six roller axial rolling molding procedure or seven roller axial rolling molding procedure or eight roller axial rolling molding procedure or nine roller axial rolling molding procedure bands circle mandrel rolling.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200310111440 CN1233481C (en) | 2003-11-24 | 2003-11-24 | Hollow drill steel rolling process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200310111440 CN1233481C (en) | 2003-11-24 | 2003-11-24 | Hollow drill steel rolling process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1544168A true CN1544168A (en) | 2004-11-10 |
| CN1233481C CN1233481C (en) | 2005-12-28 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200310111440 Expired - Fee Related CN1233481C (en) | 2003-11-24 | 2003-11-24 | Hollow drill steel rolling process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1233481C (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102039311A (en) * | 2010-09-29 | 2011-05-04 | 江苏诚德钢管股份有限公司 | Short-flow longitudinal rolling production method for small-bore high-alloy seamless steel pipe |
| 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 |
| CN103071679A (en) * | 2011-10-25 | 2013-05-01 | 都江堰市鑫奥岩土锚固材料有限公司 | One-step forming technology of hollow anchor rod |
| CN104353668A (en) * | 2014-10-08 | 2015-02-18 | 中冶赛迪工程技术股份有限公司 | Production line for rolling hollow steel and rolling forming production method for hollow steel |
| CN106552820A (en) * | 2016-12-02 | 2017-04-05 | 河南千王钎具有限责任公司 | The preparation method of hexagon cored steel |
| CN114558891A (en) * | 2022-03-04 | 2022-05-31 | 贵州捷盛钻具股份有限公司 | Hot rolling method of hollow steel for drill rod, hollow steel and hot rolling mill |
| CN114733916A (en) * | 2022-03-04 | 2022-07-12 | 贵州捷盛钻具股份有限公司 | Hollow steel hot rolling method for drill rod, hollow steel, heat insulation box and hot rolling mill |
-
2003
- 2003-11-24 CN CN 200310111440 patent/CN1233481C/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102039311A (en) * | 2010-09-29 | 2011-05-04 | 江苏诚德钢管股份有限公司 | Short-flow longitudinal rolling production method for small-bore high-alloy seamless steel pipe |
| CN103071679A (en) * | 2011-10-25 | 2013-05-01 | 都江堰市鑫奥岩土锚固材料有限公司 | One-step forming technology of hollow anchor rod |
| 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 |
| CN104353668A (en) * | 2014-10-08 | 2015-02-18 | 中冶赛迪工程技术股份有限公司 | Production line for rolling hollow steel and rolling forming production method for hollow steel |
| CN106552820A (en) * | 2016-12-02 | 2017-04-05 | 河南千王钎具有限责任公司 | The preparation method of hexagon cored steel |
| CN114558891A (en) * | 2022-03-04 | 2022-05-31 | 贵州捷盛钻具股份有限公司 | Hot rolling method of hollow steel for drill rod, hollow steel and hot rolling mill |
| CN114733916A (en) * | 2022-03-04 | 2022-07-12 | 贵州捷盛钻具股份有限公司 | Hollow steel hot rolling method for drill rod, hollow steel, heat insulation box and hot rolling mill |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1233481C (en) | 2005-12-28 |
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