CN104707870B - Hot rolling and leveling machine shape of working roll method for designing based on multistage roll shape curve matching - Google Patents

Abstract

The present invention relates to a kind of shape of working roll method for designing that can extend hot rolling and leveling machine working roll rolling milimeter number and improve product strip shape quality, refer specifically on the hot rolling and leveling machine not using roll axial float, by shape of working roll curve is designed, reach extend hot rolling and leveling machine working roll rolling milimeter number and improve the purpose of strip shape quality.The present invention uses working roll ground conth curve and the method for compensating curve superposition, forms special shape of working roll curve.Working roll ground conth curve coefficients determines according to Strip Shape Control ability and the on-the-spot practical condition of planisher, and each section of parameter of compensating curve is mainly determined by the position compensating roll wear, size and curve feature, two suite lines carry out the subregion superposition of multistage function after determining.Actual application shows that the hot rolling and leveling machine shape of working roll technology mentioned by the present invention can effectively extend the rolling milimeter number of working roll, improves the strip shape quality of product, reduces production cost.

Description

Hot rolling and leveling machine shape of working roll method for designing based on multistage roll shape curve matching

Technical field:

The present invention relates to metallurgical machinery, automatization and rolling technique, refer specifically to one by multistage curve matching with initial Roll forming is superimposed, thus improves hot rolling and leveling machine working roll rolling milimeter number and the shape of working roll design side of product strip shape quality Method.

Background technology:

On hot-rolled leveling machine production line, the plate shape of belt steel product is mainly relevant with milling train carrying roll gap shape.Impact is rolled The factor of machine carrying roll gap shape mainly has two: one to be roll forming of the roll, and two is the elastic deformation of roll.The former is at the beginning of by roll The thermal deformations of beginning roll forming, the abrasion of roll and roll etc. determine, the load that the latter is born with milling train is relevant.Different are rolled Machine, they are different to the influence degree of roll gap, are required for concrete rolling mill type and study.

Object of study herein is hot rolling and leveling machine.Hot rolling and leveling machine strip steel produce during role be to The hot-strip being cooled to room temperature imposes the small deformation of 0.5%～about 3%, is used for eliminating yield point elongation, improving mechanical property, Plate shape can also be improved simultaneously.

But, in actual production, owing to hot-strip does not the most cool down in formation process, the most do not lubricate, smooth Machine working roll there will be the most serious uneven wear；On the other hand the roll-force of planisher is smaller, causes the bullet of roll Property deformation the least, therefore, roll wear is more prominent on the impact of roll gap and plate shape thereof, badly influences the plate shape of planisher The rolling milimeter number of regulating effect and working roll.

The most fewer about the research of hot rolled strip steel leveling roll wear problem, need hot rolled strip steel leveling work The abrasion making roller is studied targetedly, to extend the rolling milimeter number of planisher working roll, reduce roller consumption and improve plate shape.

Being analyzed the work process of planisher: in formation process, owing to smooth power is less, and smooth speed is low, work Make coefficient of friction between roller and strip steel low, so the wear extent of central region should be the least；Owing to hot-strip is without place Reason directly carries out smooth, and the degree batching rear strip steel each location contacts air in coil of strip hot rolling production process is different, heat Roll the rate of cooling after the chemical composition of strip steel, rolling temperature, rolling and coiling temperature is the most different, after this causes hot rolling reeling The difference of the structure of the iron scale generated on belt steel surface, thickness and character, i.e. with coiled strip steel in width range and on The composition of oxide on lower two surfaces, the difference of heterogeneous microstructure.Fig. 1 is on-the-spot Surfaces of Hot Rolled Strip iron scale distribution Situation map.It is brown iron oxide skin in the middle part of strip steel, the oxygen mainly formed after section cooling after strip steel goes out mm finishing mill unit Changing iron sheet, its composition is mainly Fe₂O₃；And steel edge portion is blue-black iron scale, it is natural cooling after high temperature coiling Lower formation, owing to steel roll rim more can touch oxygen than center, so the oxide components of edge is more complicated, its composition Predominantly Fe₂O₃And Fe₃O₄.Due to Fe₃O₄Hardness be Fe₂O₃5-6 times of hardness, this oxide components and the difference of structure The regions wear causing subsequent hot rolled skin pass mill group working roll body of roll direction corresponding from steel edge portion is different with central region.Cause This, many than central region serious wear of abrasion of steel edge portion position, ultimately cause planisher working roller abrasion in " W " shape Distribution, as shown in Figure 2.This working roll serious uneven wear problem can cause the planisher working roll military service later stage to produce complexity Shape wave, affects the strip shape quality of product.In actual production, can only solve by reducing the rolling frequent roll change of milimeter number.This Way greatly reduces the production efficiency of production line, and ton steel cost increases substantially simultaneously.

Although there being some achievements in research at present in hot rolling and leveling machine working roller abrasion problem, but mainly concentrate on logical The methods such as the size overregulating milling train roll shifting and bending roller force improve the research of working roller abrasion, such as document 1 (hot rolled strip steel leveling The uneven wear of working roll and reduction measure thereof, 2011, Central South University's journal (natural science edition)) with 2250mm hot-strip Planisher is object, studies the uneven wear of working roll, work when utilizing model computational analysis difference shifting strategy The abrasion condition of roller, the deficiency for former strategy proposes new shifting strategy；(Wuhan Iron and Steel Plant 2250 hot rolling and leveling machine is uneven for document 2 Abrasion and plate shape modulating properties, 2009, University of Science & Technology, Beijing's journal) propose to use working roll gradually to be become to negative roller by positive roller The regulating measure changed increases milling train carrying Gap crown, to compensate the carrying that in formation process, working roller abrasion and roll shifting cause The guarantee that is decreased to of Gap crown carries the most stable of Gap crown；Document 3 (hot rolled strip steel leveling working roller abrasion Study on Problems, 2007, metallurgical equipment) propose optimize the smooth production schedule and take rational shifting strategy to improve the mill of working roll Damage situation etc..These researchs all solution cannot never possess the hot rolling and leveling machine of roll shifting function and bring due to roll uneven wear Complex wave and working roll roll the problem that milimeter number is too short.At present, what hot rolling and leveling machine working roll uneven wear brought answers Miscellaneous shape wave problem and roll roll the most not relevant research of the too short production problem of milimeter number and good solution.

Summary of the invention:

In order to solve the problems referred to above, it is an object of the present invention to provide a kind of foundation adopting on the basis of mass data statistical analysis By the roll contour design method of multistage function subregion superposition, be used for improving hot rolling and leveling machine working roll rolling milimeter number, compensate by The serious uneven wear of roll caused in raw material inherent shortcoming thus the problem causing strip shape quality to decline, increase substantially heat Offset rolling milimeter number and the strip shape quality of product of complete machine working roll.

Technical solution of the present invention specifically includes following steps:

1. the Primary Stage Data statistical analysis stage: to the shape of working roll wear data in hot-rolled leveling production line a period of time Gathering in a large number and statistical analysis, calculate the meansigma methods of abrasion on each position of the body of roll, primary Calculation goes out the abrasion of working roll Trend curve.

2. the determination of compensating curve: calculate the compensating curve of shape of working roll according to wear trend curve, due to hot rolling Planisher is limited without the regulating power of roll shifting mechanism and bending roller force, so, working roller abrasion should be symmetric.And scene is surveyed The result of amount is different from theoretical value, and when this is roll shape detecting, working roll position accomplishes that the reasons such as horizontal positioned cause the most completely , therefore, it is necessary first to the non-wearing part of wear curve is compensated on a horizontal linear, then calculate on roll surface along roller The size of each point offset on body length direction.According to this feature symmetrical of wearing and tearing, relative to the symmetry at midpoint on roll forming The offset of position should take the meansigma methods of 2 at symmetric position, thus can tentatively obtain a compensating curve, finally The non-wearing part in compensating curve topping roll two ends is moved to zero point horizontal level.

Step 3: the determination of planisher working roll compensating curve expression formula: observe compensating curve and find that it cannot be with single Mathematic(al) representation determines, accordingly, it would be desirable to carry out piecewise fitting expression according to its curve feature.Curve segmentation position is according to compensating song The feature of line determines, takes-X₀、-X₁、-X₂、X₂、X₁、X₀Main points point, is divided into seven-segment table to show compensating curve:

1) representing for first paragraph horizontal linear, formula is as follows:

Y=0 x ∈ [-X₀,-X₁]

2) can approximate for second segment and represent with straight line, formula is as follows:

Y=a₀x+d₁ x∈[-X₁,-X₂-100]

Owing to second segment straight line and first paragraph straight line are at x₁=-X₁Intersect, therefore obtain:

d₁=-a₀x₁=a₀X₁

Wherein, a₀Represent the slope of this straight line；

3) the 3rd section is changeover portion, it is ensured that second segment straight line is smoothly transitted into the 4th section of curve, uses six order polynomials bent Line is fitted, and formula is as follows:

Y=b₆x⁶+b₅x⁵+b₄x⁴+b₃x³+b₂x²+b₁x+d₂ x∈[-X₂-100,-X₂+100]

Owing to the 3rd section of curve and second segment straight line are at x₂=-X₂-100 intersect, therefore obtain:

d₂=a₀x₂+d₁-b₆x₂ ⁶-b₅x₂ ⁵-b₄x₂ ⁴-b₃x₂ ³-b₂x₂ ²-b₁x₂

Wherein, b₆、b₅、b₄、b₃、b₂、b₁It is six power curve coefficients；

4) the 4th section can be fitted with six order polynomial curves, and formula is as follows:

Y=a₆x⁶+a₅x⁵+a₄x⁴+a₃x³+a₂x²+a₁x+d₃ x∈[-X₂+100,X₂-100]

Owing to the 4th section of curve and the 3rd section of curve are at x₃=-X₂+ 100 intersect, therefore obtain:

d₃=b₆x₃ ⁶+b₅x₃ ⁵+b₄x₃ ⁴+b₃x₃ ³+b₂x₃ ²+b₁x₃+d₂-a₆x₃ ⁶-a₅x₃ ⁵-a₄x₃ ⁴-a₃x₃ ³-a₂x₃ ²-a₁x₃

Wherein, a₆、a₅、a₄、a₃、a₂、a₁It is six power curve coefficients；

5) the 5th section identical with the 3rd section of effect, it is ensured that the 4th section of curve smoothing is transitioned into the 6th section of straight line, and with the 3rd Section curve is symmetrical about working roll center line, it would however also be possible to employ six order polynomial curves are fitted, and formula is as follows:

Y=b₆x⁶-b₅x⁵+b₄x⁴-b₃x³+b₂x²-b₁x+d₂ x∈[X₂-100,X₂+100]

6) the 6th section symmetrical to working roll center line with second segment, formula is as follows:

Y=-a₀x+d₁ x∈[X₂+100,X₁]

7) the 7th section symmetrical to working roll center line with first paragraph, formula is as follows:

Y=0 x ∈ [X₁,X₀]

Therefore, working roll compensating curve can represent by below equation:

$\left\{\begin{array}{cc}y=0& x\∈[-X_0,-X_1];\\ y=a_{0}x+d_1& x\∈[-X_1,-X_2-100];\\ y=b_6{x}^6+b_5{x}^5+b_4{x}^4+b_3{x}^3+b_2{x}^2+b_{1}x+d_2& x\∈[-X_2-100,-X_2+100];\\ y=a_6{x}^6+a_5{x}^5+a_4{x}^4+a_3{x}^3+a_2{x}^2+a_{1}x+d_3& x\∈[-X_2+100,X_2-100];\\ y=b_6{x}^6-b_5{x}^5+b_4{x}^4-b_3{x}^3+b_2{x}^2-b_{1}x+d_2& x\∈[X_2-100,X_2+100];\\ y=-a_{0}x+d_1& x\∈[X_2+100,X_1];\\ y=0& x\∈[X_1,X_0].\end{array}\right.$

Wherein, X₀=L/2, L are defined as planisher working roll roll surface length；X₁=B/2, B are defined as rolled strip steel width Degree；X₂Position for roll wear amount maximum point.

4. the determination of the new roll forming of working roll: obtain being divided into the roll forming compensating curve of seven sections according to step 3, its each point roll forming value Being added to after being multiplied by penalty coefficient on planisher working roll ground conth, penalty coefficient takes between 0.2～0.5, obtains working roll New roll forming discrete points data, wherein x is the roll lateral coordinates with roll surface midpoint as initial point, unit be mm, y be roller Shape value, unit is μm, thus obtains final roll forming grinding curve.

Present invention can extend the rolling milimeter number of planisher by the design of roll shape curve, improves the plate shape of product Quality, roll contour design inputs grinding machine in the way of discrete point after completing and carries out grinding.Therefore, the present invention is at hot rolling and leveling machine On implement that feasibility is strong, low cost.Showing after certain factory's hot rolling and leveling machine uses on the machine, this kind of roll forming is remarkably improved flat The rolling milimeter number of complete machine working roll, improves product strip shape quality.

Accompanying drawing illustrates:

Fig. 1 Surfaces of Hot Rolled Strip iron scale distribution situation figure.

Fig. 2 work on the spot roller mill damages roll shape detecting figure.

Fig. 3 compensating curve segmentation position determines figure.

Fig. 4 working roller abrasion data statistics figure.

Fig. 5 working roller abrasion trendgram.

Fig. 6 working roll compensating curve figure.

Fig. 7 working roll ground conth curve.

The new roll shape curve of Fig. 8 working roll.

Fig. 9 new shape of working roll curve and ground conth curve comparison schematic diagram.

A is black and blue color iron scale；B is brown iron oxide skin.

Detailed description of the invention:

Below in conjunction with detailed description of the invention, the present invention is described further:

The phenomenon that the working roller abrasion problem that occurs for certain factory's hot rolling line planisher is serious, to its shape of working roll Improve.

According to present disclosure, design corresponding shape of working roll curve.

First add up the wear data of planisher working roll, 23 groups of data altogether in the nearly two weeks of this factory, see Fig. 4, meter Calculate the meansigma methods along the abrasion of each position of the body of roll, obtain the wear trend figure of working roll, see Fig. 5.

Offset according to wear trend curve evaluation work roller roll forming, it is necessary first to by the non-wearing part of wear curve Compensate on a horizontal linear, then calculate the size along barrel length direction each point offset on roll surface, due to working roll Wear and tear symmetrical, roll forming takes the meansigma methods of 2 at symmetric position relative to the offset of the position at midpoint, preliminary To a compensating curve, finally non-for compensating curve two ends wearing part is moved to zero point horizontal level, obtain final compensation Curve, is shown in Fig. 6.

Then the compensating curve obtained being carried out piecewise fitting, formula is as follows:

It is first paragraph curve when x ∈ [-900 ,-720], y=0；

It is second segment curve when x ∈ [-720 ,-640], y=0.1788x+128.97；

It is the 3rd section of curve when x ∈ [-640 ,-440],

$\begin{array}{c}y=-1.016\×{10}^{-11}{x}^6-3.263\×{10}^{-8}{x}^5-4.35\×{10}^{-5}{x}^4-0.0307x^3-12.142x^2-2549.105x\\ -221972.90\end{array};$

It is the 4th section of curve when x ∈ [-440,440],

$\begin{array}{c}y=-3.41\×{10}^{-15}{x}^6-1.06\×{10}^{-27}{x}^5+1.50\×{10}^{-9}{x}^4-1.49\×{10}^{22}{x}^3-4.05{\×{10}^{-5}x}^2\\ -3.51\×{10}^{-18}x+1.0309\end{array};$

It is the 5th section of curve when x ∈ [440,640],

$\begin{array}{c}y=-1.016\×{10}^{-11}{x}^6+3.263\×{10}^{-8}{x}^5-4.345\×{10}^{-5}{x}^4+0.0307x^3-12.142x^2+2549.105x\\ -221972.90\end{array};$

It is the 6th section of curve when x ∈ [640,720], y=-0.1788x+128.97；

It is the 7th section of curve when x ∈ [720,900], y=0.

The ground conth of planisher working roll is the recessed roll forming of-60 μm, sees Fig. 7；Employing conic section function representation:

Y=7.407 × 10^-5x²-60 x∈[-900,900]

After above roll forming segment design completes, curve is overlapped, according to the real work situation of planisher, takes compensation Coefficient is 0.25, and compensating curve is overlapped with ground conth after being multiplied by penalty coefficient, i.e. can get new shape of working roll.Combine Conjunction formula is as follows:

When x ∈ [-900 ,-720], y=7.407 × 10^-5x²-60；

When x ∈ [-720 ,-640], y=7.407 × 10^-5x²+0.0447x-27.7575；

When x ∈ [-640 ,-440],

$\begin{array}{c}y=-0.254\×{10}^{-11}{x}^6-8.158\×{10}^{-9}{x}^5-1.0875\×{10}^{-5}{x}^4-7.675\×{10}^{-3}{x}^3-3.035426x^2\\ -637.2762x-55553.225\end{array};$ When

During x ∈ [-440,440],

$\begin{array}{c}y=-8.525\×{10}^{-16}{x}^6-2.65\×{10}^{-28}{x}^5+3.75\×{10}^{-10}{x}^4+2.98\×{10}^{-23}{x}^3+6.397{\×{10}^{-5}x}^2\\ -8.775\×{10}^{-19}x-59.7423\end{array};$

When x ∈ [440,640],

$\begin{array}{c}y=-0.254\×{10}^{-11}{x}^6+8.158\×{10}^{-9}{x}^5-1.0875\×{10}^{-5}{x}^4+7.675{\×{10}^{-3}x}^3-3.035426x^2\\ +637.276x-55553.225\end{array};$

When x ∈ [640,720], y=7.407 × 10^-5x²-0.0447x-27.7575；

When x ∈ [720,900], y=7.407 × 10^-5x²-60。

The laterally discrete point data of roll (interval mono-point of 25mm) can be calculated according to formula above, such as table 1 institute Showing, x is the roll lateral coordinates with roll midpoint as initial point, unit mm, and y is roll forming of the roll value, and unit is μm.Fig. 8 is newly The shape of working roll of design；Fig. 9 is new design work roller roll shape curve and original initial roll shape curve comparison diagram.

The laterally discrete point data of table 1 working roll

x	y	x	y	x	y
						-900	0.00	-275	-53.13	350	-47.85
-875	-3.29	-250	-54.49	375	-45.70
						-850	-6.48	-225	-55.65	400	-43.40
-825	-9.59	-200	-56.64	425	-40.98
						-800	-12.60	-175	-57.46	450	-38.47
-775	-15.51	-150	-58.12	475	-36.05
						-750	-18.34	-125	-58.65	500	-33.61
-725	-21.23	-100	-59.07	525	-31.48
						-700	-22.75	-75	-59.37	550	-29.94
-675	-24.18	-50	-59.58	575	-28.96
						-650	-25.52	-25	-59.70	600	-27.99
-625	-26.77	0	-59.74	625	-26.77
						-600	-27.99	25	-59.70	650	-25.52
-575	-28.96	50	-59.58	675	-24.18
						-550	-29.94	75	-59.37	700	-22.75
-525	-31.48	100	-59.07	725	-21.23
						-500	-33.61	125	-58.65	750	-18.34
-475	-36.05	150	-58.12	775	-15.51
						-450	-38.47	175	-57.46	800	-12.60
-425	-40.98	200	-56.64	825	-9.59
						-400	-43.40	225	-55.65	850	-6.48
-375	-45.70	250	-54.49	875	-3.29
						-350	-47.85	275	-53.13	900	0.00
-325	-49.81	300	-51.57
						-300	-51.57	325	-49.81

Data above is input to grinding machine and carries out grinding, obtain new shape of working roll and carry out upper machine production.

Actual production shows: hot rolling and leveling machine is by using newly-designed shape of working roll, and strip shape quality objection have dropped 36%, flatness defect is effectively controlled；The average rolling milimeter number of planisher working roll is increased to by original 540 kilometers 960 kilometers, greatly reducing a ton steel rider consumption, the grinding roller number of times and the hot rolling and leveling machine that decrease roll dressing workshop raw simultaneously Produce the roll change frequency of line, greatly improve the operating rate producing line, bring huge economic benefit for enterprise.

The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for the skill of this area For art personnel, the present invention can have various modifications and variations.All within the spirit and principles in the present invention, by roll forming technology Improve that planisher working roll rolling milimeter number that roll uneven wear brought is low and under strip shape quality, degradation problem is made Any modification, equivalent substitution and improvement etc., should be included within the scope of the present invention.

Claims (1)

1. hot rolling and leveling machine shape of working roll method for designing based on multistage roll shape curve matching, it is characterised in that this roll forming is bent Line uses the mode that ground conth curve superposes with compensating curve segmentation, specifically comprises the following steps that

Step 1: Primary Stage Data statistical analysis stage: to the shape of working roll wear data in hot-rolled leveling production line a period of time Gather in a large number and statistical analysis, the wear extent of statistics each position of the body of roll, obtain the average of each position wear extent of the body of roll Value, thus obtain the wear trend curve of working roll；

Step 2: the determination of compensating curve: according to the compensating curve of wear trend curve evaluation work roller roll forming, it is necessary first to will It is straight line that the non-wearing part in working roll two ends that wear trend curve is corresponding compensates, and then calculates on roll surface along barrel length The size of direction each point roll forming offset, owing to working roller abrasion is symmetrical, on roll forming relative to the symmetric position at midpoint at Offset take the meansigma methods of 2, tentatively obtain a compensating curve, finally by the non-wear in two ends corresponding for compensating curve Divide and move to dead-center position；

Step 3: the determination of planisher working roll compensating curve expression formula: owing to compensating curve cannot be with single mathematic(al) representation Determining, accordingly, it would be desirable to carry out segmentation expression according to its curvilinear characteristic, segmentation position determines according to the feature of compensating curve, first Definition-X₀、-X₁、-X₂、X₂、X₁、X₀Main points point, compensating curve divides seven sections to represent respectively, and formula is as follows:

1) first paragraph horizontal linear represents, formula is as follows:

,,

2) second segment can approximate and represent with straight line, and formula is as follows:

,,

Owing to second segment straight line and first paragraph straight line existIntersect, therefore obtain:

,

Wherein,Represent the slope of this straight line；

3) the 3rd section is changeover portion, it is ensured that second segment straight line is smoothly transitted into the 4th section of curve, uses six order polynomial curves to enter Row matching, formula is as follows:

,,

Owing to the 3rd section of curve and second segment straight line existIntersect, therefore obtain:

,

Wherein,、、、、、It is six power curve coefficients；

4) the 4th section is fitted with six order polynomial curves, and formula is as follows:

,,

Owing to the 4th section of curve and the 3rd section of curve existIntersect, therefore obtain:

, wherein,、、、、、It is six power curve coefficients；

5) the 5th section identical with the 3rd section of effect, it is ensured that the 4th section of curve smoothing is transitioned into the 6th section of straight line, and with the 3rd section of song Line is symmetrical about working roll center line, uses six order polynomial curves to be fitted, and formula is as follows:

,,

6) the 6th section symmetrical to working roll center line with second segment, formula is as follows:

,,

7) the 7th section symmetrical to working roll center line with first paragraph, formula is as follows:

,,

Wherein, X₀=L/2, L are defined as planisher working roll roll surface length；X₁=B/2, B are defined as rolled strip width；X₂ For the position of roll wear amount maximum point,

Step 4: the determination of the new roll forming of working roll: obtain being divided into the roll forming compensating curve of seven sections according to step 3, its each point roll forming value Being added to after being multiplied by penalty coefficient on planisher working roll ground conth, penalty coefficient takes between 0.2 ~ 0.5, obtains working roll new Roll forming discrete points data, wherein x is the roll lateral coordinates with roll surface midpoint as initial point, unit be mm, y be roll forming of the roll Value, unit is m, thus obtains final roll forming grinding curve.