CN204182678U - A kind of four roller rotary rolling mill - Google Patents
A kind of four roller rotary rolling mill Download PDFInfo
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- CN204182678U CN204182678U CN201420607126.0U CN201420607126U CN204182678U CN 204182678 U CN204182678 U CN 204182678U CN 201420607126 U CN201420607126 U CN 201420607126U CN 204182678 U CN204182678 U CN 204182678U
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Abstract
The feature of this four rollers rotary rolling mill is less roll off angle, and be generally 0 ° ~ 10 °, rolled piece is nipped by the small end of roll, shuts out from the large end of roll.Be different from existing planetary rolling to limit due to structure and must adopt large roll off angle, be generally 35 ° ~ 60 °, rolled piece is nipped by the large end of roll, shuts out from small end.The rolled piece internal material flowing of this four rollers rotary rolling mill is identical with instrument linear velocity direction.Because rolled piece is nipped from roll small end, shut out from the large end of roll, operation of rolling roller surface linear velocity increases gradually, with rolled piece material along with the change that extension line speed goes is large is consistent, weaken the slippage of rolled piece material internal and the wearing and tearing to instrument, be more conducive to flowing and the extension of metal.The roll of this four rollers rotary rolling mill can change roller curve according to ideal technology, and Strain During Finishing Stage can reach 2.5 ~ 3 times of workpiece diameters.Be conducive to eliminating rolled piece thread surface, improve dimensional accuracy.
Description
Technical field
The invention belongs to seamless steel pipe planetary oblique rolling technical field, be specifically related to a kind of four roller rotary rolling mill.
Background technology
The production equipment extensively adopted in seamless steel tube production field is at present three-roll planetary mill and four roller planetary cross-mills.
One, three-roll planetary mill
The cone-shaped roll that three-roll planetary mill uses 120 °, three intervals to distribute is rolled rolled piece.Collar revolves round the sun around rolled piece, thus their inner surface forms the deformed area of a taper, because roller declination is arranged, makes rolled piece produce feed motion and by deformed area, thus not need to nip and guider while it rotates.In working continuously, this milling train passes can obtain the percentage elongation of the tandem mill being equivalent to 5 to 8 frames.Roll is driven by an epicyclic train by mair motor.Roll can planetary gear axis tilt on deep bid, and to obtain the roll drift angle produced required for feed motion, another motor is for superposing transmission, and its drives the sun gear in planet circular system, for eliminating any fine rotation of rolled piece.Three-roll planetary mill can to rolled piece finished product cross dimensions stepless changing within a large range, and without the need to changing the hole type design of roll.Different sections requires to obtain simply by the position of synchronous adjustment three cone-shaped rolls.
Three-roll planetary mill under quality index requires, can obtain or better result the same with other milling methods for all.Tissue and the grain flow of rolled material show, the rolling result of three-roll planetary mill has no difference compared with the result of traditional milling method.
The rolled piece that three-roll planetary mill rolls has spiral channel in various degree, and its height is relevant with roll, but can not affect the quality of follow-up rolling or peeling.The workpiece diameter tolerance that three-roll planetary mill rolls can reach 0.75% of its size.
Feature is comprehensive: l, heavy reduction, and the economic percentage elongation of single pass can reach 5 ~ 8; 2, rolled piece non rotating or micro-turn, milling train has good tandem rolling performance; 3, without guide and guard, rolling is stablized.4, the material of energy rolling difficulty distortion; 5, intensification rolling, ensures the temperature requirement of subsequent handling.
Compared with other skew rolling mills, except different on motion mode, outside namely roll rotates around rolled piece, the idea of this technology is also very unique, and rolled piece can become very large angle with the axis of roll, and this can produce following effect:
1), material does not twist in deformation process.This is large for the contraction percentage of area, and is very necessary during rolling thin-wall pipe.
2), larger feeding angle can be realized.The feed angle of conventional mill is 6 ° ~ 12 °, and three-roller planetary rolling mill is 30 ° ~ 40 °, thus greatly improves the deformation efficiency of oblique roll process, can obtain the effect same with axial rolling.
Two, four roller planetary cross-mills
The main feature of four roller planetary rolling tube rolling production new techniques is tandem rollings, combines, form a set of continuous print operating system by extension process (four roller planetary rollings) and finishing rolling step (sizing or stretch reducing).
Four roller planetary rolling tube rolling production technologies summarize the advantage of traditional extension mode, its production technology is as follows: porch hollow bloom being delivered to four roller planetary rollings, plug plug, then four roller planetary rolling shaping districts are sent into, after plug position is determined, hollow hollow forging rolls into, and has reached very high lengthening coefficient.
In the outlet of four roller planetary rollings, the hollow forging after rolling automatically disengages plug, and can directly enter sizing mill or stretch-reducing mill, rolls into the production tube of certain external diameter and wall thickness.Because four roller planetary rollings do not adopt floating core rod, and lengthening coefficient is very high, therefore large 3 ~ 4 times of the weight ratio conventional mill of its blank used.The increase of blank quality also just means that the lumber recovery of Tube Rolling Train improves.
The production effect of four roller planetary rollings:
1), the wall thickness dimension scope of pipe is all wider than all traditional handicrafts.
2), one of four roller planetary rollings important advantage is exactly that blank quality is very large.As the hollow bloom that 8m is long rolled into the long hollow forging of 50m, in this case (as oil field tubulars), lumber recovery can reach 90% ~ 92%.
3), four roller planetary rollings are higher than three traditional rollers, double-roll rolling mill productivity ratio.One of its reason is that mill speed is high, and four roller elongators are higher than three rollers or two roller elongator, because feeding speed can improve with the increase of roller quantity.By reducing rotating mass as far as possible, the speed of roll can significantly improve, thus boosts productivity.
4), the bottleneck that thin-wall steel tube is Cross-rolling elongation milling train is produced.Four roller planetary rollings, compared with traditional Cross-rolling elongation milling train, in production thin-wall steel tube, because roll quantity is many, solve the problem of tail triangle and have the advantage can not replacing analogy.
The production length of pipe evaluates the important symbol of Tube Rolling Train.Four roller planetary rollings not only make product specification convert flexibly, and can produce long tube, up to the present, also can not reach such length with additive method.The maximum length of current production pipe depends primarily on elongator, generally at 15 ~ 40m.And when adopting four roller planetary rollings, tube length depends on perforation process.Use four roller planetary rollings, the lengthening coefficient of pipe can reach 12, and pipe range is not by the restriction of instrument (plug).Such as, the hollow bloom of 10m can be rolled into the hollow forging that 120m is long.
The shortcoming of current three-roller planetary rolling mill and four roller planetary rolling milling trains:
1, efficiency is low, and namely mill speed is low.Mill speed can reach 1m/s in theory, and general practical rolling speed is at about 0.5m/s.
2, for large-scale three-roller planetary rolling mill milling train and four roller planetary rollings, because its revolution deep bid is comparatively large, to part energy be consumed during rotation, and be very high away from its linear velocity of rotating part of rolling centerline.Therefore in the design rotating part lubricating system is required strict.To reliability of structure being strengthened simultaneously, avoiding, when producing, catastrophic failure occurs.
3, when rolling difficult-to-deformation material, because roll is tapered, Strain During Finishing Stage is " thin " very, and roll wear is serious.
4, in actual production, when some difficult distortion of rolling, temperature range narrow special steel can be rolled time.Rolled piece can be there is broken by finishing above.Tail triangle is stayed in roll, causes the stuck imagination of milling train.The reason of this phenomenon is caused to be slide owing to being out of shape during three-roller planetary rolling mill mill milling after back zone exists.When rolled piece is about to roll, rolled piece rear portion forms cavity, and when rolled piece continues to nip, cavity part is crushed, and frictional force reduces, and rolled piece muzzle velocity reduces, and rolled piece tail temperature reduces rapidly, and resistance of deformation increases rapidly, thus causes milling train to kill phenomenon.
5, rolled piece surface easily produces spiral lamination, affects surface quality.In the ordinary course of things, when being furnished with Precise asymptotics below, to three-roller planetary rolling mill milling train rolled piece surface quality do not become topic.If excessive for three-roller planetary rolling mill pipe mill drafts, rolled piece perficial helical line is also not easily eliminated on sizing mill.The reason affecting perficial helical line is a lot, as rolled piece material, and rolling temperature, frictional force size and drafts etc., the double thread degree of depth all has impact, if do not controlled rolled piece quality, can cause irremediable sad office, the bankruptcy of Hunter company of U.S. pipe rolling plant is exactly an example.
The rolling direction of these two kinds of milling trains is all that pipe is nipped from the large end of cone-shaped roll above, shuts out from small end through roll off.Because rolling mill structure needs to arrange travelling gear, larger roll off angle must be adopted.Cause the different diameters of roll concentric reducer a lot.In the operation of rolling, the linear velocity elongatedness direction of roller rotational diminishes gradually, and amplitude of variation is very large, and the linear velocity of rolled piece reduces to become large gradually with diameter, and amplitude of variation is also very large.This just causes the sliding friction between roll and rolled piece.Roll-force increases, and plant capacity increases, and tool wear speeds, service life reduction.
Because forming process instrument hinders the flowing of material, this fatal shortcoming causes these two kinds of milling train major parts can only rolling nonferrous metal tube, and bearing life is short, and roll wear is fast, and instrument cost is very high.Even if there is indivedual factory producing ferrous metal pipe, output is also very low.
Summary of the invention
The object of this invention is to provide a kind of four roller rotary rolling mill.
The present invention four roller rotary rolling mill, is characterized in that being made up of gearbox shaft bearing, gear case body, central gear, auxiliary drive motor, box bearing lid, planetary gear, adpting flange, the first shaft coupling, the second shaft coupling, rolling mill bearing lid, screwdown gear, backing roll, rolling-mill housing, main drive motor, roll, rolling mill bearing;
Described gearbox shaft bearing can be separated along horizonally split face up and down with box bearing lid;
Described rolling mill bearing lid can be separated along horizonally split face up and down with rolling mill bearing;
Gearbox shaft bearing two ends rolling bearing supporting gear box body; Rolling mill bearing two ends rolling bearing supporting rolling-mill housing; Two ends, gear case body center rolling bearing bearing center gear; Gear case body two ends are centrally uniformly distributed 4 planetary gears of rolling bearing supporting;
Rolling-mill housing center be uniformly distributed 4 with the rectangle gathering sill of end slope, described rectangle gathering sill installs roll, screwdown gear, backing roll;
Gear case body, rolling-mill housing, adpting flange, the as a whole revolving body of the first shaft coupling high strength exploitation;
It is 4 revolving bodies that 4 planetary gears are connected with the second shaft coupling with output shaft roll, 4 central gears and 47 planetary gear engaged transmission;
4 central gear planetary gears, roll form planet circular system transmission;
Auxiliary drive motor, gearbox shaft bearing, box bearing lid are fixedly connected with, and auxiliary drive motor central gear key connects;
Main drive motor, rolling mill bearing, rolling mill bearing lid fixed-link, main drive motor, rolling-mill housing are fixedly connected with, and main drive motor driven gear box body, adpting flange, the first shaft coupling, the second shaft coupling, rolling-mill housing rotate.
The feature of this four rollers rotary rolling mill is less roll off angle, and be generally 0 ° ~ 10 °, rolled piece is nipped by the small end of roll, shuts out from the large end of roll.Be different from existing planetary rolling to limit due to structure and must adopt large roll off angle, be generally 35 ° ~ 60 °, rolled piece is nipped by the large end of roll, shuts out from small end.The rolled piece internal material flowing of this four rollers rotary rolling mill is identical with instrument linear velocity direction.Because rolled piece is nipped from roll small end, shut out from the large end of roll, operation of rolling roller surface linear velocity increases gradually, with rolled piece material along with the change that extension line speed goes is large is consistent, weaken the slippage of rolled piece material internal and the wearing and tearing to instrument, be more conducive to flowing and the extension of metal.
The roll of this four rollers rotary rolling mill can change roller curve according to ideal technology, and Strain During Finishing Stage can reach 2.5 ~ 3 times of workpiece diameters.Be conducive to eliminating rolled piece thread surface, improve dimensional accuracy.
The roll of this four rollers rotary rolling mill has longer round gauge section.Be conducive to improving rolled piece geometric accuracy.
(1) this four rollers rotary rolling mill is made up of (see Fig. 1 tetra-roller rotary rolling mill) main driving permanent magnet synchronous torque motor, process auxiliary drive permanent magnet synchronous torque motor, gear-box, circular rolling-mill housing, roll device, screwdown gear, support roller device, coupling system;
(2) in these four rollers rotary rolling mill two ends, two permanent magnet synchronous torque motors are installed, one is main drive motor, being used for driven wheel box body and circular rolling-mill housing rotates, then the rotation of four rolls is driven, another is auxiliary drive motor, be used for adjusting roll rotational speed, to ensure that rolled piece does not turn in the operation of rolling;
(3) this four rollers rotary rolling mill middle gear case forms a planet circular system by a central gear and four planetary gears;
(4) in this four rollers rotary rolling mill, four rolls and back-up chock are arranged in four slide-and-guide grooves of frame respectively, make the operation of rolling more stable;
(5) the throat size that four rolls of four screwdown gear adjustable in this four rollers rotary rolling mill are formed;
(6) planet pin of this four rollers rotary rolling mill middle gear case is connected with roll mandrel shaft coupling;
(7) gear-box of this four rollers rotary rolling mill is connected with circular rolling-mill housing shaft coupling;
(8) main drive motor of this four rollers rotary rolling mill is directly connected with circular rolling-mill housing, and auxiliary drive motor is directly connected with gear-box central gear;
(9) there is bearing at the gear-box of this four rollers rotary rolling mill and circular rolling-mill housing two ends, can synchronous rotary under the drive of main drive motor;
(10) four rolls of this four rollers rotary rolling mill are by the transmission of gear-box train, can synchronous rotary under the drive of stand-by motor;
(11) the roll off angle of this four rollers rotary rolling mill is 0 ° ~ 10 °, and rolled piece is nipped by the small end of roll, shuts out from the large end of roll;
(12) roll of this four rollers rotary rolling mill can change roller curve according to ideal technology, and Strain During Finishing Stage can reach 2.5 ~ 3 times of workpiece diameters;
(13) roll of this four rollers rotary rolling mill has longer round gauge section;
(14) compact conformation of this four rollers rotary rolling mill, appearance and size is little, and all bearings all can select standard rolling bearing;
(15) the roll drafts of this four rollers rotary rolling mill can accurate adjustment separately, and the dimensional accuracy of rolled piece is not by the inconsistent impact brought of each roll wear.
Accompanying drawing explanation
Fig. 1 the present invention four roller rotary rolling mill profile.
Fig. 2 the present invention four roller rotary rolling mill schematic perspective view.
Detailed description of the invention
The invention will be further described for embodiment plan given below; but can not be interpreted as it is limiting the scope of the invention; those skilled in the art to nonessential improvement and adjustment more of the present invention, still belong to protection scope of the present invention according to content of the present invention.
Four roller rotary rolling mill, as shown in Fig. 1, Fig. 2.Four roller rotary rolling mill are made up of gearbox shaft bearing 1 gear case body 2 rolled piece central gear 4 auxiliary drive motor 5 box bearing lid 6 planetary gear 7 adpting flange 8 first shaft coupling 9 second shaft coupling 10 rolling mill bearing lid 11 screwdown gear 12 backing roll 13 rolling-mill housing 14 main drive motor 15 roll 16 rolling mill bearing 17.
The central axis of rolled piece is rolling centerline.The cylindrical housings of gear case body 2 to be one with rolling centerline be axle.The cylindrical housings of rolling-mill housing 14 to be one with rolling centerline be axle.Gearbox shaft bearing 1 can be separated along horizonally split face up and down with box bearing lid 6.Rolling mill bearing lid 11 can be separated along horizonally split face up and down with rolling mill bearing 17.Gear case body 2 adpting flange 8 first shaft coupling 9 second shaft coupling 10 rolling-mill housing 14 will be divided into several parts by overall revolution wheel body in the past.Gearbox shaft bearing 1 two ends rolling bearing supporting gear box body 2.Rolling mill bearing 17 two ends rolling bearing supporting rolling-mill housing 14.Two ends, gear case body 2 center rolling bearing bearing center gear 4.Gear case body 2 two ends are centrally uniformly distributed 4 pairs of rolling bearing supportings, 4 planetary gears 7.Planetary gear 7 is connected with output axle key.Rolling mill bearing 17 two ends rolling bearing supporting rolling-mill housing 14.Rolling-mill housing 14 center be uniformly distributed 4 with the rectangle gathering sill of end slope.Roll 16 screwdown gear 12 backing roll 13 is installed in groove.Roll 16 is connected with output axle key.The gear case body 2 rolling-mill housing 14 adpting flange 8 first shaft coupling 9 as a whole revolving body of high strength exploitation.It is 4 revolving bodies that 4 planetary gears 7 are connected with output shaft second shaft coupling 10 with output shaft roll 16.Central gear 4 and 4 planetary gear 7 engaged transmission.Roll 16 and rolled piece frictional drive.Central gear 4 planetary gear 7 roll 16 rolled piece forms planet circular system transmission.Auxiliary drive motor 5 gearbox shaft bearing 1 box bearing lid 6 is fixedly connected with.Auxiliary drive motor 5 central gear 4 key connects.Main drive motor 15 rolling mill bearing 17 rolling mill bearing lid 11 fixed-link.Main drive motor 15 rolling-mill housing 14 is fixedly connected with.Main drive motor 15 driven gear box body 2 adpting flange 8 first shaft coupling 9 second shaft coupling 10 rolling-mill housing 14 rotates.Auxiliary drive motor 5 drives central gear 4 to rotate.Then because planetary gear 7 carries out spiral roll off around central gear 4 revolution from transferring to produce roll 16 pairs of rolled pieces.The rotating speed of suitable adjustment main drive motor 15 auxiliary drive motor 5 realizes rolled piece non rotating.Rolled piece is rolled into by roll 16 step taper roll shape small end and shuts out from large end.Rolled piece uninterruptedly can extend into leader mill without torsion continuously along rolling centerline and realize continuous rolling.
Roll 16 increases gradually along rolling direction linear velocity.Rolled piece increases gradually along rolling direction linear velocity.This milling method is shaped very favourable to metal flow.This is the difference maximum with other planetary rolling technology of this technology.
Claims (1)
1. four roller rotary rolling mill, is characterized in that being made up of gearbox shaft bearing, gear case body, central gear, auxiliary drive motor, box bearing lid, planetary gear, adpting flange, the first shaft coupling, the second shaft coupling, rolling mill bearing lid, screwdown gear, backing roll, rolling-mill housing, main drive motor, roll, rolling mill bearing;
Described gearbox shaft bearing can be separated along horizonally split face up and down with box bearing lid;
Described rolling mill bearing lid can be separated along horizonally split face up and down with rolling mill bearing;
Gearbox shaft bearing two ends rolling bearing supporting gear box body; Rolling mill bearing two ends rolling bearing supporting rolling-mill housing; Two ends, gear case body center rolling bearing bearing center gear; Gear case body two ends are centrally uniformly distributed 4 planetary gears of rolling bearing supporting;
Rolling-mill housing center be uniformly distributed 4 with the rectangle gathering sill of end slope, described rectangle gathering sill installs roll, screwdown gear, backing roll;
Gear case body, rolling-mill housing, adpting flange, the as a whole revolving body of the first shaft coupling high strength exploitation;
It is 4 revolving bodies that 4 planetary gears are connected with the second shaft coupling with output shaft roll, 4 central gears and 47 planetary gear engaged transmission;
4 central gear planetary gears, roll form planet circular system transmission;
Auxiliary drive motor, gearbox shaft bearing, box bearing lid are fixedly connected with, and auxiliary drive motor central gear key connects;
Main drive motor, rolling mill bearing, rolling mill bearing lid fixed-link, main drive motor, rolling-mill housing are fixedly connected with, and main drive motor driven gear box body, adpting flange, the first shaft coupling, the second shaft coupling, rolling-mill housing rotate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420607126.0U CN204182678U (en) | 2014-10-21 | 2014-10-21 | A kind of four roller rotary rolling mill |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420607126.0U CN204182678U (en) | 2014-10-21 | 2014-10-21 | A kind of four roller rotary rolling mill |
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| CN204182678U true CN204182678U (en) | 2015-03-04 |
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| CN201420607126.0U Withdrawn - After Issue CN204182678U (en) | 2014-10-21 | 2014-10-21 | A kind of four roller rotary rolling mill |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104307875A (en) * | 2014-10-21 | 2015-01-28 | 太原普莱设工程技术有限公司 | Four-roll rotary rolling mill |
| CN110270590A (en) * | 2019-06-20 | 2019-09-24 | 北京科技大学 | A kind of double rotary shaft flexibility skew rolling mills |
| CN112024605A (en) * | 2020-09-07 | 2020-12-04 | 中冶赛迪工程技术股份有限公司 | Four-roller reducing mill with frame changed at one side through double inputs in same direction |
-
2014
- 2014-10-21 CN CN201420607126.0U patent/CN204182678U/en not_active Withdrawn - After Issue
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104307875A (en) * | 2014-10-21 | 2015-01-28 | 太原普莱设工程技术有限公司 | Four-roll rotary rolling mill |
| CN110270590A (en) * | 2019-06-20 | 2019-09-24 | 北京科技大学 | A kind of double rotary shaft flexibility skew rolling mills |
| US11612919B2 (en) | 2019-06-20 | 2023-03-28 | University Of Science And Technology Beijing | Flexible skew rolling mill with dual-rotatable-shafts |
| CN112024605A (en) * | 2020-09-07 | 2020-12-04 | 中冶赛迪工程技术股份有限公司 | Four-roller reducing mill with frame changed at one side through double inputs in same direction |
| CN112024605B (en) * | 2020-09-07 | 2024-05-17 | 中冶赛迪工程技术股份有限公司 | Four-roller reducing mill with homodromous double-input single-side frame replacing function |
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| AV01 | Patent right actively abandoned |
Granted publication date: 20150304 Effective date of abandoning: 20160810 |
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| C25 | Abandonment of patent right or utility model to avoid double patenting |