CN104588549B - Multi-ring roll-forming method for thin ring parts - Google Patents

Abstract

The invention discloses a multi-ring roll-forming method for thin ring parts to solve the problems of the prior art that during thin ring part processing, production efficiency is low and the performance of annular parts is poor. The method comprises the steps of 1, blank manufacturing, wherein a first annular part blank is manufactured; 2, rolling groove designing; 3, forming parameter designing; 4, roll forming, wherein the first annular part blank is arranged on a core roller (2) in a sleeving mode, the core roller (2) moves upwards to roll the first annular part blank, the next step is executed after a second annular part blank is formed by rolling the first annular part blank, the core roller (2) moves downwards till the second annular ring part blank is clamped by the core roller (2) and a second driving roller (6), deep groove rolling is conducted and finished after the depth of a deep groove reaches a predetermined value so that a third annular part blank can be formed, the third annular part blank is taken down, inner ring burrs on the third annular part blank are removed through a lathe, the three thin ring part blanks are separated, and the flat end faces of the thin ring part blanks are finally machined to obtain qualified thin annular parts.

Description

The multi-ring roll-forming method of slim ring

Technical field

A kind of a kind of the present invention relates to roll-forming method of ring-shaped work pieces, it more particularly relates to slim ring The multi-ring roll-forming method of part.

Background technology

Refering to Fig. 2, ring geometric properties shown in figure is height h very little, and diameter is very big, and ratio of height to diameter is generally less than 1:25, Such ring is referred to as slim ring, and it often applies to automobile axle reinforcing ring.Reinforcing ring is important zero of automobile axle Part, its effect not only accepts total reduction device assembly and axle housing, and strengthens in the middle part of axle housing, so by this ring working environment, Determine it and must have higher intensity.Nowadays such slim ring processing method mainly has plasma cutting, casting, welding Deng, and above processing method all has a lot of defects.Such as plasma cutting, the reinforcing ring stay in grade that it processes, Good welding performance, but because plasma cutting speeds are slow, greatly reduce production efficiency, thus also have impact on the warp of enterprise Ji benefit；Although and cast and welding also can process qualified ring, due to casting and welding process in, metal Inside has a series of defect such as bubble, crackle it is impossible to ensure the mechanical property of this ring, causes this ring service life Short, thus largely effecting on this ring quality.It is known that ring rolling is the most effectual way of production and processing ring, it is not only Ensure that ring quality, and production efficiency is high.If but such slim ring directly utilizes ring rolling, rolling Easily the defects such as distortion occur in journey, so tending not to enough directly carry out production and processing with ring rolling.

Content of the invention

The technical problem to be solved is to overcome low production efficiency and ring in the existing slim ring course of processing A kind of problem of part poor performance, there is provided the multi-ring roll-forming method of slim ring.

For solving above-mentioned technical problem, the present invention adopts the following technical scheme that realization：Described slim ring is multi-ring The step of roll-forming method is as follows：

1) base：

Described base prepares No. 1 ring blank；

2) rolling groove design：

Described rolling groove design is driven roller and the design of core roller, and its step is as follows：

(1) driven roller and the diameter of core roller work surface are determined：

In order that No. 1 ring blank can either continuously nip in the operation of rolling and ensure that ring can be forged, driven roller Following condition should be met with core roller diameter：

Driven roller and core roller limit radius R₁And R₂：

In formula：R_1min、R_2min, R, r be respectively in least radius and No. 1 ring blank of driven roller and core roller work surface Outer radius, unit is mm；β=arctan μ is angle of friction, and μ is coefficient of friction, is taken as 0.5 for 45 steel；

(2) driven roller maximum radius is allowed by ring rolls driven roller and core roller center are away from size limitation；Core roller Maximum radius not can exceed that No. 1 ring blank internal bore radius；

(3) core roll shape chamber size design：

Core roller is designed as enclosed pass, die cavity width B₀Minima can not be more than the wall thickness of No. 1 ring blank；Die cavity height h_c=h₁+ 0.3～0.5mm, core roll shape cavity dumping degree α value is α=1 °～3 °；And in the die cavity face of cylinder and core roller 2 up/down steps Place carries out chamfering R_C, value is taken as R_C=3mm, die cavity up/down steps height value is h_t=h；

(4) second driven roller size design

The effect of the second driven roller is that No. 2 ring blanks are cut into three connected slim ring blanks, concrete size As follows：

Radius of clean-up R of the second driven roller₃Radius R equal to driven roller₁：I.e. R₃=R₁；

The height h of the second driven roller_s1=h_s2+2h+2h₃+ f, f are at the upper and lower two cylindrical surface of the second driven roller two outside the boss Exceed the height value of single slim ring, take

Height h between two structure identical boss_s2=h+ λ h, λ take 0.01；Two boss sections are all designed as isosceles ladder Shape, and design fillet R in outside the boss_S, its value is R_S=R-0.1～0.3mm, wherein R are the circle of 3 ring part blank groove Angular radius, its concrete size is as follows：

Boss inside heightOutside heightFlare radius R_S=0.5mm；

Boss is used for slot portion width：Wherein a is gross weight thickness at the end of 3 ring part blank rolling Degree.

3) forming parameter design：

Forming parameter design selects the forming parameter of driven roller rotating speed and feed rate of idle roll, and its step is as follows：

(1) driven roller rotary speed n₁Represent：Wherein：V is feed speed, and unit is mm/s；△h For feed of every rotation, unit is mm；

(2) all play a role in two rolling sequences in operation of rolling SMIS roller, core roller can be upper and lower by hydraulic cylinder Mobile, feed rate of idle roll is directly proportional to feed of every rotation, and it had not only met and ensure that ring forging thoroughly but also guarantee ring can be just Often nip, so its ultimate value is as follows：

In formula：R₁、R₂It is respectively the radius of driven roller and core roller, R, r are respectively the outer, inside radius of No. 1 ring blank, single Position is mm；β=arctan μ is angle of friction, and μ is coefficient of friction；

(3) during rolling deep trouth, in order to ensure that the second driven roller can smoothly cut No. 2 ring blanks, initial Stage core roller adopts the little amount of feeding, prevents the flow of metal when cutting No. 2 ring blanks of core roller serious, when carrying out rolling steady Using large inflow；It is to reduce feed speed it is ensured that full circle quality in the full circle stage.

4) roll forming：

(1) No. 1 ring blank is enclosed within core roller, core roller moves No. 1 ring blank of rolling, when rolling No. 1 ring blank System is configured to during No. 2 ring blanks enter next step；

(2) core roller is displaced downwardly to and with the second driven roller, No. 2 ring blanks is clamped, roll deep trouth, when deep trouth reach pre- During sizing, deep trouth rolling sequence terminates to be configured to 3 ring part blank；

(3) taking off 3 ring part blank adopts lathe car to remove the inner ring gross weight on 3 ring part blank, three slim ring hairs Base separates, and finally processes qualified slim ring to slim ring blank flat end face.

Base described in technical scheme comprises the steps：

1) determine 3 ring part blank volume V：

Wherein：D is 3 ring part blank external diameter, and unit is millimeter；D is the internal diameter after 3 ring part blank removes gross weight, single Position is millimeter；h₁For 3 ring part blank whole height at the end of rolling, unit is millimeter；h₂For groove height inside deep trouth, unit For millimeter；h₃For groove height outside deep trouth, unit is millimeter；A is Web thickness, and unit is millimeter；

2) determine that K is compared in rolling：

The ring rolling ratio of square-section is taken as K=1.5～3；

3) determine No. 1 ring blank height：

Using enclosed groove rolling, No. 1 ring blank whole height is h₁=3h+2h₃, wherein h is finally single slim ring The height of part；

4) determine No. 1 ring blank internal diameter d₀And outer diameter D₀:

Based on plastic deformation constancy of volume principle, and ring rolling highly determines No. 1 ring hair than with 3 ring part blank Base internal diameter d₀And outer diameter D₀For

5) designed according to above, blanking first, bar is heated in electric furnace 1200 DEG C, then by bar in forcing press On carry out jumping-up, punching, remove gross weight, and elimination internal stress of annealing, be finally rolled into the torus that radial section is square-section No. 1 ring blank of shape.

Compared with prior art the invention has the beneficial effects as follows：

1. the multi-ring roll-forming method of slim ring of the present invention is directed to and produces in the slim ring course of processing at present Efficiency is low, the defect such as ring poor performance, by rational design rolling technological parameter it is proposed that the concept of " grinds multi-ring ", that is, Disposably grind three slim ring blanks, be equivalent to and blank is manufactured with the height more than 3 times of original slim ring rolled, Thus returning in the roll-forming method of general rectangle ring.

2. refer to Fig. 9, implement only original vertical ring rolling machine simply to be changed during the multi-ring roll-forming method of slim ring Make, on the basis of original ring rolls, the symmetric position of driven roller is installed one and carries the roll of " cutting knife " and this is ground The core roller of ring machine is set to feed rolls, is so conducive to core roller can play a role in two rolling sequences；Rolling ring after repacking Machine can make two benches carry out on same ring rolls and without taking off ring, which save the time, increased work effect Rate, decreases equipment investment.

3. the multi-ring roll-forming method of slim ring of the present invention effectively improves slim ring cutting, casting in the past Low production efficiency in manufacture process, some column defects such as ring poor performance such as make, weld, and can process within a short period of time Go out qualified product, improve production efficiency, and saved processing cost, considerably increase economic benefit.

Brief description

The present invention is further illustrated below in conjunction with the accompanying drawings：

Fig. 1 is the FB(flow block) of the multi-ring roll-forming method of slim ring of the present invention；

Fig. 2 is on slim ring front view in embodiment in the multi-ring roll-forming method of slim ring of the present invention Full sectional view；

Fig. 3 is slim ring of the present invention multi-ring roll-forming method rolling principle schematic diagram；

Fig. 4 is No. 1 ring blank that the multi-ring roll-forming method of slim ring of the present invention is adopted is initial Full sectional view on ring blank front view；

Fig. 5 is the 3 ring part blank being processed using the multi-ring roll-forming method of slim ring of the present invention is Full sectional view on two rolling sequences final drip molding front view；

Fig. 6 is the partial enlarged view of the deep groove structure between two slim ring blanks at A in Fig. 5；

Fig. 7 is in the ring rolls after implementing the repacking that the multi-ring roll-forming method of slim ring of the present invention is adopted Driven roller front view on full sectional view；

Fig. 8 is in the ring rolls after implementing the repacking that the multi-ring roll-forming method of slim ring of the present invention is adopted Core roller front view on full sectional view；

Fig. 9 is in the ring rolls after implementing the repacking that the multi-ring roll-forming method of slim ring of the present invention is adopted The second driven roller front view on full sectional view；

Figure 10 is the partial enlarged view of the second driven roller boss at B in Fig. 9；

In figure：1. driven roller, 2. core roller, 3. guide roller, 4. ring, 5. signal roller, 6. the second driven roller.

Specific embodiment

Below in conjunction with the accompanying drawings the present invention is explained in detail：

Refering to Fig. 1, when being rolled using the multi-ring roll-forming method of slim ring of the present invention, determine No. 1 first The shape of ring blank and volume；Require to design rational rolling groove further according to slim ring；It is then determined that forming parameter； Last roll forming.First ring 4 is placed on core roller 2 when being rolled, then on core roller 2 move, treat No. 1 ring blank with During driven roller 1 contact, start the first rolling sequence, the i.e. rolling of square-section No. 2 ring blank；To be rolled to certain size Shape No. 2 ring blanks, core roller 2 moves down, and so that No. 2 ring blanks is contacted with the second driven roller 6, start the operation of rolling of deep trouth I.e. the second rolling sequence, until being rolled into 3 ring part blank, then utilizes lathe to remove 3 slim rings on 3 ring part blank Gross weight between part blank, so that 3 slim ring blanks are separated, finally processes to slim ring blank flat end face Qualified slim ring.

The step of the multi-ring roll-forming method of slim ring of the present invention is as follows：

1. base：(No. 1 ring blank of preparation)

The step of No. 1 ring blank of preparation is as follows：

1) determine 3 ring part blank volume V：

Wherein：D is 3 ring part blank external diameter, and unit is millimeter；D is the internal diameter after 3 ring part blank removes gross weight, single Position is millimeter；h₁For 3 ring part blank whole height at the end of rolling, unit is millimeter；h₂For groove height inside deep trouth, unit For millimeter；h₃For groove height outside deep trouth, unit is millimeter；A is Web thickness, and unit is millimeter.

2) determine that K is compared in rolling：

The ring rolling of square-section is taken as K=1.5～3 than typically, and when ring external diameter is larger, K value obtains greatly a bit, Smaller value is taken it is contemplated that this slim ring external diameter is larger, so rolling ratio takes higher value to be 2.5 when less.

3) determine No. 1 ring blank height：

Using enclosed groove rolling, No. 1 ring blank whole height is h₁=3h+2h₃, wherein h is finally single slim ring The height of part.

4) determine No. 1 ring blank internal diameter d₀And outer diameter D₀:

Based on plastic deformation constancy of volume principle, and ring rolling highly determines No. 1 ring blank internal diameter than with ring d₀And outer diameter D₀For

5) refer to Fig. 4, designed according to above, blanking first, bar is heated in electric furnace 1200 DEG C, then by bar Jumping-up, punching are carried out on forcing press, removes gross weight, and elimination internal stress of annealing, finally it is rolled into No. 1 ring blank；I.e. No. 1 ring The blank of the part Blank Design radially annulus bodily form in rectangular cross-section section.

2. rolling groove design：

3 ring part blank forming process is divided into No. 2 ring blank rolling sequences and deep trouth rolling sequence.No. 2 ring blanks , mainly by driven roller 1 and core roller 2 roll forming, its process is as rectangle ring roll form process for rolling sequence；And deep trouth Rolling by the second driven roller 6 and the common roll forming of core roller 2, its process similar to " cutting " process, due to being to be rolled into Shape, so making 3 ring part blank maintain metallic continuity well, part performance keeps good.Driven roller 1 shape designs For cylinder；In order to limit the axial direction flowing of metal in the grooving stage, core roller 2 is designed as enclosed pass, thus ensureing well The end face quality of grooving stage 3 ring part blank.And the second driven roller 6 shape of working surface and the final roll forming of ring blank When shape corresponding, driven roller 1 and core roller 2 design size as follows：

1) driven roller 1 and the diameter of core roller 2 work surface are determined：

In order that No. 1 ring blank can either continuously nip in the operation of rolling and ensure that ring can be forged, driven roller 1 Following condition should be met with core roller 2 diameter：

Driven roller 1 and core roller 2 limit radius (R₁And R₂)：

In formula：R_1min、R_2min, R, r be respectively the least radius of driven roller 1 and core roller 2 work surface and No. 1 ring blank Interior outer radius, unit is mm；β=arctan μ is angle of friction, and μ is coefficient of friction, is typically taken as 0.5 for 45 steel.

2) certain, also restricted for driven roller 1 and their maximum radius of core roller 2, driven roller 1 maximum radius is ground Driven roller 1 and core roller 2 centre-to-centre spacing size limitation that ring machine is allowed；And the maximum radius of core roller 2 not can exceed that No. 1 ring blank Internal bore radius, otherwise No. 1 ring blank can not be inserted in core roller 2.

3) core roller 2 cavity dimension design：

In order to ensure that No. 2 ring blanks, in the end face quality that the second body rolling sequence is deep trouth rolling sequence, prevent " fish Tail " and warping phenomenon, core roller 2 is designed as enclosed pass, and its die cavity width B₀Minima can not be more than the wall of No. 1 ring blank Thick；Die cavity height h_c=h₁+ 0.3～0.5mm, so contributes to No. 1 ring blank and puts in die cavity well, and arrange core roller Die cavity gradient α, its value takes α=1 °～3 °；And carry out chamfering R at the die cavity face of cylinder with core roller 2 up/down steps_C, its value Take R_C=3mm, to prevent distortion；Inoperative to ring rolling due to it for die cavity up/down steps height, be simply Limit metal axial flowing during ring rolling well, so hard requirement do not done to its height be taken as h_t=h.

4) the second driven roller 6 size design

The effect of the second driven roller 6 is mainly when No. 1 ring blank is rolled down to preliminary dimension, and No. 2 ring blanks are divided It is segmented into three connected slim ring blanks, that is, similar to " cutting " process, its concrete shape and final cutting forming Slim ring is corresponding, and concrete size is as follows：

Radius of clean-up R of the second driven roller 6₃Radius R equal to driven roller 1₁：I.e. R₃=R₁；

The height h of the second driven roller 6_s1=h_s2+2h+2h₃+ f, in the second driven roller 6, two structure identical boss are mainly used In No. 2 ring blanks of second stage " cutting ", f is for ensureing 6 liang of outside the boss of ring stable rolling the second driven roller upper and lower two Exceed the height value of single slim ring at the face of cylinder, typically takeAnd two height h between boss_s2=h+ λ h, λ typically take 0.01；In order to reduce the rolling resistance in the operation of rolling, two boss sections are all designed as isosceles trapezoid, and in outside the boss design Fillet R_S, its value is R_S=R-0.1～0.3mm, wherein R are the radius of corner of 3 ring part blank groove, are so conducive to convex Platform can smoothly cut No. 2 ring blanks, and greatly reduces stress concentration, so that this process is smoothed out.It is concrete Size is as follows：

Boss inside heightOutside heightFlare radius R_S=0.5mm；

Boss is used for slot portion width：Wherein a is gross weight thickness at the end of 3 ring part blank rolling Degree.

3. forming parameter design：

Forming parameter mainly includes driven roller 1 rotating speed, core roller 2 feed speed, and design is as follows：

1) driven roller 1 rotary speed n₁Represent：Wherein：V is feed speed, and unit is mm/s；△h For feed of every rotation, unit is mm.

2) due to all playing a role in two rolling sequences in operation of rolling SMIS roller 2, so core roller 2 is set to feed Roller, and being moved up and down by hydraulic cylinder, to ensure in the operation of rolling and driven roller 1 or the second driven roller 6 can Contact.Core roller 2 feed speed is directly proportional to feed of every rotation, and it should not only meet and ensure that ring forging thoroughly but also should be ensured that ring Part can normally nip, so its ultimate value is as follows：

In formula：R₁、R₂It is respectively the radius of driven roller 1 and core roller 2, R, r are respectively the outer, inside radius of No. 1 ring blank, Unit is mm；β=arctan μ is angle of friction, and μ is coefficient of friction.

3) during rolling deep trouth, in order to ensure that the second driven roller 6 can smoothly cut No. 2 ring blanks, initial Stage core roller 2 adopts the less amount of feeding, prevents core roller 2 flow of metal when cutting No. 2 ring blanks serious, flat carrying out rolling Using compared with large inflow when steady, save the time, improve productivity ratio, be to reduce feed speed it is ensured that full circle quality in the full circle stage.

4. roll forming：

1) No. 1 ring blank is enclosed within core roller 2, core roller 2 moves No. 1 ring blank of rolling, its process is equivalent to rectangle The ring rolling process in section, enters next when being rolling to No. 1 ring blank when preliminary dimension is configured to No. 2 ring blanks Step；

2) core roller 2 is displaced downwardly to and is clamped No. 2 ring blanks with the second driven roller 6, rolls deep trouth, assumes in this process No. 2 ring blank internal diameters are constant, flowed mostly to according to metal fluidity and constant-volume principle deep trouth metal and so that external diameter is increased, when Deep trouth reaches deep trouth rolling sequence during preliminary dimension to be terminated, that is, shape 3 ring part blank.

3) taking off 3 ring part blank adopts lathe car to remove the inner ring gross weight on 3 ring part blank, three slim ring blanks Separate, qualified slim ring is finally processed to slim ring blank flat end face.

Embodiment：

Refering to Fig. 2, in figure is the slim ring that need to process, and slim ring is certain automobile axle reinforcing ring, this ring geometry A size of：Slim ring outside diameter D_OutwardFor 506mm, i.e. D_Outward=506mm, interior circular diameter d_InteriorFor 424mm, d_Interior=424mm, highly H is 20mm, i.e. h=20mm.

The step of the multi-ring roll-forming method of slim ring is as follows：

1. base：

Refering to Fig. 2, disposably roll three slim rings through the final determination of finite element modelling, according to finally roll out Multiple slim ring schematic cross-sections (Fig. 5), determine this rolling mill practice according to constancy of volume principle in metal plastic forming processes Required blank volume is 3801893.16mm³, and assume that No. 2 ring blank internal diameters are constant in second operation of rolling, can obtain Going out No. 2 ring blanks of rectangle a size of external diameter that the first rolling sequence finally gives is D₂=499mm, internal diameter is d₂=422mm； Designed according to ring blank, determine that rolling ratio is 2.5, finally determine the outer diameter D of No. 1 ring blank₀=315.3mm, internal diameter is d₀ =168.8mm, highly for h₁=68mm.

2. rolling groove design

1) according to driven roller 1 and core roller 2 dimension limit design requirement, in this clad-rolling process, the work of driven roller 1 is straight Footpath is designed as 400mm, highly for 70mm；

2) core roller 2 working diameter is designed as 150mm, and in order to prevent metal axial flowing in the operation of rolling, core roller designs For enclosed pass, its die cavity height h_cIt is designed as 68+0.3～0.5mm, and die cavity boss downside inclined angle alpha takes 1 °, so has Help ring smoothly to put in die cavity, and projection width B₀It is designed as 40mm, take boss height h_tFor falling inside 20mm, and die cavity Angle R_CFor 1 °～3 °；

3) due to the not very specific reference frame of this deep groove annular piece roller milling roller size design, temporarily referring also to straight-flanked ring Dimension of roller design requirement in the part operation of rolling, design the second driving roller diameter drives with the first stage that roller diameter is identical to be 400mm, height h_s1It is designed as 68mm, projection width B₁For 41mm, and boss inside height h_s3For 4mm, outside height h_s2For 2mm, and in outside chamfering R_sFor 0.5mm, inside two boss between be highly h_s2For 20.2mm；

3. forming parameter design：

In ring first rolling sequence, in order to ensure that ring can forge, and can continuously nip driven roller rotating speed and set It is set to 10rad/s, feed rate of idle roll is set to 1.5mm/s；Second rolling sequence the second driven roller rotating speed is also configured as 10rad/s, and in order to prevent the rolling of ring deep trouth, just the incipient stage enters dosage excessive metal generation Severe distortion, starts just Using less amount of feeding 1mm/s；When comparison to be rolled is steady, the amount of feeding is increased to 2mm/s, in order to protect at the end of waiting rolling fast Card ring rolling is stable, and keeps full circle effect preferably, and the amount of feeding is adjusted to 0.8mm/s, until rolling terminates.

4. roll forming：First No. 1 ring blank is enclosed within core roller 2, then makes to move on core roller 2 by hydraulic system, When No. 1 ring blank is contacted with driven roller 1, stop move, then driven roller 1 rotates, rotating speed be 10rad/s, core roller 2 with The little amount of feeding of 1.5mm/s, to upper feeding, starts ring first rolling sequence, and No. 1 ring blank diameter starts to increase, treats outside ring When footpath reaches preliminary dimension 499mm, that is, it is configured to No. 2 ring blanks, No. 2 ring blanks are contacted with signal roller 5, thus equipment is sent out Go out termination signal, core roller 2 moves down, and with No. 2 ring blank lower contacts, at this moment in the second driven roller 6 move, until with No. 2 rings Part blank contacts, beginning the second rolling sequence, i.e. deep trouth rolling sequence, and now the second driven roller 6 rotating speed is set to 10rad/s, , first with 1mm/s feeding, when comparison to be rolled is steady, the amount of feeding is increased to 2mm/s, in order to ensure ring at the end of waiting rolling fast for core roller 2 Part rolling is stable, and keeps full circle effect preferably, and the amount of feeding is adjusted to 0.8mm/s, until 3 ring part blank forming, entirely Looping mill rolling process terminates.Then 3 ring part blank is taken off, then carries out boring, car removes the gross weight between three slim ring blanks, And carry out planar end surface, finally process standard compliant slim ring.

Claims (2)

1. a kind of multi-ring roll-forming method of slim ring is it is characterised in that the described multi-ring roll-forming method of slim ring Step as follows：

1) base：

Described base prepares No. 1 ring blank；

2) rolling groove design：

Described rolling groove design is driven roller (1) and the design of core roller (2), and its step is as follows：

(1) driven roller (1) and the diameter of core roller (2) work surface are determined：

In order that No. 1 ring blank can either continuously nip in the operation of rolling and ensure that ring can be forged, driven roller (1) and Core roller (2) diameter should meet following condition：

Driven roller (1) and core roller (2) limit radius R₁And R₂：

In formula：R_1min、R_2min, R, r be respectively the least radius of driven roller (1) and core roller (2) work surface and No. 1 ring blank Interior outer radius, unit is mm；β=arctan μ is angle of friction, and μ is coefficient of friction, is taken as 0.5 for 45 steel；

(2) driven roller (1) maximum radius is allowed by ring rolls driven roller (1) and core roller (2) centre-to-centre spacing size limitation；Core The maximum radius of roller (2) not can exceed that No. 1 ring blank internal bore radius；

(3) core roll shape chamber size design：

Core roller (2) is designed as enclosed pass, die cavity width B₀Minima can not be more than the wall thickness of No. 1 ring blank；Die cavity height h_c =h₁+ 0.3～0.5mm, core roll shape cavity dumping degree α value is α=1 °～3 °；And in the die cavity face of cylinder and core roller 2 up/down steps Place carries out chamfering R_C, value is taken as R_C=3mm, die cavity up/down steps height value is h_t=h；

(4) second driven roller (6) size design

The effect of the second driven roller (6) is that No. 2 ring blanks are cut into three connected slim ring blanks, and concrete size is such as Under：

Radius of clean-up R of the second driven roller (6)₃Radius R equal to driven roller (1)₁：I.e. R₃=R₁；

The height h of the second driven roller (6)_s1=h_s2+2h+2h₃+ f, f are the upper and lower two cylindrical surfaces of the second driven roller (6) two outside the boss Place exceeds the height value of single slim ring, takes

Height h between two structure identical boss_s2=h+ λ h, λ take 0.01；Two boss sections are all designed as isosceles trapezoid, and Design fillet R in outside the boss_S, its value is R_S=R-0.1～0.3mm, wherein R are the fillet half of 3 ring part blank groove Footpath, its concrete size is as follows：

Boss inside heightOutside heightFlare radius R_S=0.5mm；

Boss is used for slot portion width：Wherein a is Web thickness at the end of 3 ring part blank rolling；

3) forming parameter design：

Forming parameter design selects the forming parameter of driven roller (1) rotating speed and core roller (2) feed speed, and its step is as follows：

(1) driven roller (1) rotary speed n₁Represent：Wherein：V is feed speed, and unit is mm/s；△ h is Feed of every rotation, unit is mm；

(2) all play a role in two rolling sequences in operation of rolling SMIS roller (2), core roller (2) pass through hydraulic cylinder can more than Lower movement, core roller (2) feed speed is directly proportional to feed of every rotation, and it had not only met and ensure that ring forging thoroughly again guarantee ring energy Enough normally nip, so its ultimate value is as follows：

$v\≥v_{\min }=6.55\×{10}^{-3}{n}_1\frac{R_1^2}{R}{(\frac{R}{R_1}-\frac{r}{R_1})}^2(1+\frac{R_1}{R_2}+\frac{R_1}{R}-\frac{R_1}{r})$

$v\≤v_{max}=\frac{2{\mathrm{\β}}^2{n}_1{R}_1^2}{{(1+\frac{R_1}{R_2})}^2}(1+\frac{R_1}{R_2}+\frac{R_1}{R}-\frac{R_1}{r})$

In formula：R₁、R₂It is respectively the radius of driven roller (1) and core roller (2), R, r are respectively the outer, inside radius of No. 1 ring blank, Unit is mm；β=arctan μ is angle of friction, and μ is coefficient of friction；

(3) during rolling deep trouth, in order to ensure that the second driven roller (6) can smoothly cut No. 2 ring blanks, in initial rank Section core roller (2) adopts the little amount of feeding, prevents core roller (2) flow of metal when cutting No. 2 ring blanks serious, flat carrying out rolling Large inflow is adopted when steady；It is to reduce feed speed it is ensured that full circle quality in the full circle stage；

4) roll forming：

(1) No. 1 ring blank is enclosed within core roller (2), core roller (2) is upper to move No. 1 ring blank of rolling, when by No. 1 ring blank Roll forming is to enter next step during No. 2 ring blanks；

(2) core roller (2) is displaced downwardly to and with the second driven roller (6), No. 2 ring blanks is clamped, roll deep trouth, when deep trouth reaches During preliminary dimension, deep trouth rolling sequence terminates to be configured to 3 ring part blank；

(3) taking off 3 ring part blank adopts lathe car to remove the inner ring gross weight on 3 ring part blank, and three slim ring blanks divide From qualified slim ring is finally processed to slim ring blank flat end face.

2. according to the multi-ring roll-forming method of slim ring described in claim 1 it is characterised in that described base include as Lower step：

1) determine 3 ring part blank volume V：

$V=\frac{\mathrm{\π}}{4}\[D^2-{(d-2a)}^2\]h_1-\frac{\mathrm{\π}}{4}(D^2-d^2)(h_2+h_3)$

Wherein：D is 3 ring part blank external diameter, and unit is millimeter；D is the internal diameter after 3 ring part blank removes gross weight, and unit is Millimeter；h₁For 3 ring part blank whole height at the end of rolling, unit is millimeter；h₂For groove height inside deep trouth, unit is milli Rice；h₃For groove height outside deep trouth, unit is millimeter；A is Web thickness, and unit is millimeter；

2) determine that K is compared in rolling：

The ring rolling ratio of square-section is taken as K=1.5～3；

3) determine No. 1 ring blank height：

Using enclosed groove rolling, No. 1 ring blank whole height is h₁=3h+2h₃, wherein h is final single slim ring Highly；

4) determine No. 1 ring blank internal diameter d₀And outer diameter D₀:

Based on plastic deformation constancy of volume principle, and ring rolling highly determines in No. 1 ring blank than with 3 ring part blank Footpath d₀And outer diameter D₀For

$d_0=\frac{d}{k}$

$D_0=\sqrt{\frac{\[D^2-{(d-2a)}^2\]h_1-(D^2-d^2)(h_2+h_3)}{h_1}+{\left(\frac{d}{k}\right)}^2};$

5) designed according to above, blanking first, bar is heated in electric furnace 1200 DEG C, then that bar is enterprising in forcing press Row jumping-up, punching, remove gross weight, and elimination internal stress of annealing, finally it is rolled into the 1 of the annulus bodily form that radial section is square-section Number ring blank.