CN104874615B - Bar Wire Product pass low temperature controlled rolling power of motor sharing of load method for designing - Google Patents

Abstract

A kind of Bar Wire Product pass low temperature controlled rolling power of motor sharing of load method for designing, belongs to steel rolling engineering design and production technical field.Method flow is as follows: design is new produces the steel grade resistance of deformation of line product mix → Gleeble thermal simulation measured and emulate every time rolling deformation → simulation under the actual pass of Bar Wire Product as input parameter → employings DEFORM finite element software and calculate the power of every time roll-force nipping, roll and throwing steel process → calculate roll torque → calculate milling train.Advantage is: the calculating of roll-force has taken into full account in each passage pass in diverse location point deformation temperature actual distribution difference, pass diverse location point strain rate actual distribution difference etc. first in diverse location point dependent variable actual distribution difference, pass.It is current calculation rod wire-rod pass low temperature controlled rolling power of motor method the most accurately, thus produces line milling train rated power distribution design for new and zerolling the technological parameter important and reliable basis of offer is provided.

Description

Bar Wire Product pass low temperature controlled rolling power of motor sharing of load method for designing

Technical field

The invention belongs to steel rolling engineering design and production technical field.Particularly relate to a kind of Bar Wire Product pass low temperature controlled rolling Power of motor sharing of load method for designing, produces line design for new and formulate low temperature controlled rolling parameter offer important evidence.

Background technology

Low temperature controlled rolling can significantly improve the serviceability of a lot of steel grade, reduce subsequent handling and process costs etc..Therefore, In recent years, low temperature controlled rolling technology increasingly came into one's own and extensively applied.Its major advantage is as follows: 1. avoid the most again Crystallization, it is thus achieved that the finished product of crystal grain refinement, improves the toughness of some steel grade；2. avoid partial, re-crystallization district, reduce mixed crystal, Improve impact flexibility；3. the subsequent heat treatment time (such as bearing steel, spring steel) of some steel grade is shortened；4. machinery is improved The fatigue strength of part；5. reduce the oxidization burning loss of steel, improve surface quality of steel, especially surface decarburization phenomenon (such as cord steel)；6. yield strength and toughness of material are improved；7. improve dislocation density, increase line defect strengthening effect, Postpone bainitic transformation and start temperature spot, thus ensure that also in meet pearlite+ferritic structure, mechanical property, Welding performances etc. reduce the usage amounts (such as high-strength screw-thread steel) such as microalloy V, Nb under the conditions of using.

Realize every time rated power that the most important condition of low temperature controlled rolling is milling train and should meet low temperature process requirement.Low temperature control Roll and can be through to whole rolling process, including low temperature open rolling, low temperature roughing, low temperature roll, the pre-finish rolling of low temperature, low Temperature finish rolling etc., current Low Temperature Finish even can reach 700-800 DEG C.Owing to each passes all exists temperature rise, especially Its heart portion temperature rise is very big, so in addition to heating furnace low temperature is come out of the stove, it is necessary between milling train, arrange water cooling equipment, and This further increases the heart table temperature difference, particularly with Bar Wire Product groove rolling, pass complex-shaped various (as square hole, Circular hole, flat-rolled hole, edging pass for rolling, ellipse hole, dumbbell hole, double Pedicellus et Pericarpium Trapae cutting hole, four ellipse precutting holes, four ellipse cutting holes, spiral shell Pit etc.), exacerbate rod, the full face temperature of wire rod and flow of metal distributional difference.Wire and rod continuous rolling unit quantity is few Then 18 frame, reaches 30 sorties at most, how appropriate design each sortie rated power burden apportionment, is in design When zerolling newly produces line, it is necessary to the major issue of consideration, if the design of milling train rated power is little, then do not reach low temperature Technological requirement, if power designs is big, then early investment fund strengthens, and later stage energy consumption is high, ton steel rolling cost is high. Equally, also must carry out in existing milling train rated power when formulating concrete zerolling technological parameter.

Along with process-technology-evolutions, currently requiring that bar and wire rod rolling process temperature is more and more lower, mill speed is increasingly faster, During new product line design, the milling train power configuration table accumulated by former many years of experience cannot indiscriminately imitate use, needs to redesign Milling train rated power.And promote requirement to meet product specification, produce line design and require more and more personalized and have Particular craft feature, it is impossible to simple copy.

Milling train power loading size is mainly determined by roll-force, the most commonly used Ai Ke Longde (Ekelund) etc. Some formula Theoretical Calculation roll-forces, and then measuring and calculating power, facts have proved that the formula such as Ekelund are calculating stress in a large number During the thin plate rolling power that direction is the most single and proximate freedom spreads accuracy still can, substantially can be suitable for, but at rod line During complicated pass zerolling, precision is very poor, and main cause is that it fails to consider Bar Wire Product section of pass deformation difference, and Rolling temperature is the lowest, and compound section deformation difference is the biggest, often misleads the reasonable selection of power of motor.Existing roll Acc power computational methods are primarily present following problem:

[1] for simple relative to stress and the thin plate of proximate freedom boradside rolling, Bar Wire Product pass, especially zerolling Tunneling boring Temperature Distribution difference huge, Fig. 1 be rolling Φ 6.5mm specification hypereutectoid high-carbon steel wire rod temperature curve, Can be seen that some passage heart table temperature difference is up to 200 DEG C, and this cross-section temperature difference is difficult to use simple mathematical Model is accurately expressed, it is clear that the formula such as Ekelund do not consider this section heart table temperature difference.

[2] Bar Wire Product pass zerolling tunneling boring dependent variable distributional difference is huge, such as Fig. 2, advises for wire rod Φ 6.5mm Lattice hypereutectoid high-carbon steel wire rod rolling the 27th passage cross section dependent variable distribution field, dependent variable about 0.2 minimum in pass, Maximum reaches 0.9.The formula such as Ekelund do not consider this section dependent variable difference.

[3] Bar Wire Product pass zerolling tunneling boring strain rate distributional difference is huge, such as Fig. 3, wire rod the 28th passage Rolling section maximum strain speed reaches 15000s^-1, minimum only about 2000s^-1.The formula such as Ekelund do not consider This section strain rate difference.

At present both at home and abroad also do not have a set of to count accurately at rod string holes type low temperature controlled rolling power of motor sharing of load design field Calculation method.The advantage of patent of the present invention is: the calculating to roll-force has taken into full account tunneling boring in each passage pass Tunneling boring deflection actual distribution in tunneling boring deformation velocity actual distribution, pass in deformation temperature actual distribution, pass Deng, computational accuracy increases substantially.It it is current calculation rod wire rod low temperature controlled rolling power of motor method the most accurately.Thus Produce line milling train rated power distribution design for new and zerolling technological parameter offer reliable basis is provided.

Summary of the invention

It is an object of the invention to provide a kind of Bar Wire Product pass low temperature controlled rolling power of motor sharing of load method for designing, meter Calculation flow process is as follows: design new product line product mix → Gleeble thermal simulation measures the resistance of deformation of steel grade as input ginseng Number → use every time rolling deformation → simulation under the DEFORM finite element software simulation actual pass of Bar Wire Product to calculate Go out the power of every time roll-force nipping, roll and throwing steel process → calculate roll torque → calculate milling train.Tool Body technology step is as follows:

1, the new line product mix that produces of design: first, it is settled that produce steel grade and the minimum temperature requirement of rolling involved by line, complete Different size pass parameters designs, and the steel grade selecting resistance of deformation maximum carries out subsequent calculations: its rolling temperature requires Maximum (the C of low (750-800 DEG C), carbon equivalent_eq>=0.54%), mill speed the fastest (bar 15-20m/s, wire rod 110-150m/s)。

2, the resistance of deformation of steel grade is measured: use single pass compression to measure on Gleeble3000 hot modeling test machine, Specimen size is Φ 6mm × 15mm, 15 altogether.Austenitizing temperature 1250 DEG C, is incubated 5min, deformation temperature Degree 1073K, 1173K, 1223K, 1273K, 1323K respectively.Strain rate takes 0.1s respectively^-1、1s^-1、10 s^-1, engineering strain 50%, water-cooled immediately after having compressed, make strain stress curve, wherein strain rate is 1s^-1 Strain stress curve experiments result as shown in Figure 4.

3, every time the operation of rolling under the actual pass of employing DEFORM finite element software simulation:

(1) thermal simulation resulting materials strain stress curve is input in DEFORM material depot, newly-built material depot；

(2) Pro/Engineer WildFire (the CAD/CAM/CAE integration three under PTC S. A. of the U.S. is utilized Dimension software) set up rolled piece, roll 3-D geometric model, generate stl file；

(3) utilize DEFORM to import 3-D geometric model, set up rolling geometric model, carry out stress and strain model；

(4) utilize rolling schedule rolling parameter as rolling model roll, the initial condition of workpiece motion s；

(5) the temperature field contrast correction calculated by field measurement temperature and simulation, determines the table between rolled piece and roll The face coefficient of heat transfer, guarantees the accuracy of rolling model with the accuracy of temperature calculation models.

4, use DEFORM to simulate and calculate every time roll-force nipping, roll and throwing steel process:

(1) roll is considered as rigid body, and rolled piece is considered as plastic body, calculates according to rigid plasticity finite element, can accurately determine The roll-force of steel process is nipped, rolls and thrown to each passage rolled piece；

(2) according to roll-force time changing curve, take roll-force maximum of points and calculate as milling train rated power.

5, according to tube rolling simulation roll torque M_Z, drive moment M of a roll_KFor roll torque M_ZWith roll Moment of friction M at bearing_f1Sum.

M_K=M_Z+M_f1=P (a+ ρ₁)

$P=P_{m}S=P_m\frac{b_0+b_1}{2}l$

P roll-force, kN；The a roll-force arm of force, the i.e. vertical dimension of two roll centre lines of force action line-spacing, Mm,ρ₁Friction circle radius at roll bearingmm；P_mAverage unit pressure, MPa；b₀、b₁Roll forward and backward rolled piece width, mm；L contact arc length extent of horizontal projection degree, mm；D rolls Roller diameter, mm；β point of resultant force angle, °；D roll pins having diameter, mm；The friction of μ roll bearing is Number, rolling bearing μ=0.004.

6, the power N of milling train is calculated according to roll torque_D: design motor rated power further according to overload condition.

$N_D=M_{\mathrm{er}}\mathrm{\ω}=\frac{\mathrm{\π}{M}_{\mathrm{er}}{n}_{\mathrm{er}}}{30}$

$M_{\mathrm{er}}=\frac{M_{\max }}{K}$

M_erRated static torque, k Nm；M_maxMaximum moment on static load figure, k Nm；n_erMotor is specified Rotating speed, r/min；K electromotor overload coefficient, non reversible motor K=1.5～2.0.

It is an advantage of the current invention that: the calculating to roll-force has taken into full account diverse location point in each passage pass first Not coordination in deformation temperature actual distribution difference (as some passage tunneling boring temperature difference is up to more than 200 DEG C), pass Put in a dependent variable actual distribution difference (the tunneling boring dependent variable scope such as some passage reaches 0.2-0.9), pass not (the tunneling boring strain rate scope such as some passage reaches co-located point strain rate actual distribution difference 2000s^-1-15000s^-1) etc..It is current calculation rod wire-rod pass low temperature controlled rolling power of motor method the most accurately, thus Produce line milling train rated power distribution design for new and zerolling technological parameter offer reliable basis is provided.

Accompanying drawing explanation

Fig. 1 wire rod Φ 6.5mm specification hypereutectoid high-carbon steel wire rod rolls the temperature curve that 28 passages are omnidistance.

Fig. 2 wire rod Φ 6.5mm specification hypereutectoid high carbon rolling the 27th passage cross section dependent variable field distribution.

The strain rate values of Fig. 3 wire rod Φ 6.5mm specification hypereutectoid high carbon rolling 28 passage whole process diverse location.

Fig. 4 steel grade true stress-true strain curve, (strain rate is 1s^-1Time).

Fig. 5 Φ 10mm HRB600E (14-19# sortie) temperature curve (two sections of water-cooleds, 18# water-cooleds the last period before 14#).

Fig. 6 Φ 10mm HRB600E (19# sortie) nips, rolls and throws the roll-force curve of steel process.

The peak power contrast that Fig. 7 present invention and two kinds of algorithms of Ekelund are obtained.

Detailed description of the invention

Embodiment 1:

Certain newly-built bar produces line, and its rolling mill practice basic demand is as shown in table 1.

Table 1 rolling mill practice requirement

According to Product Process requirement in table 1, calculate the power required for each specification, each steel grade every a time milling train of rolling, Relatively draw maximum, on this basis, design every a time rated power of milling train.

Calculate as a example by five line cutting φ 10mm specifications HRB600E, its finished product mill speed 16.3m/s, essence Milling train group is respectively 14#, 15#, 16#, 17#, 18#, 19#, carries out two sections of water-cooleds, it is ensured that 14# before 14# finishing mill Finishing mill entrance rolled piece surface temperature 780 DEG C, 18# milling train water-cooled the last period ensures that 18# inlet of rolling mill surface temperature is 780 DEG C, the tunneling boring temperature curve of simulation calculation is as it is shown in figure 5, the 19# mill milling force curve calculated is as schemed Shown in 6, and then its rolling power can be obtained.

By that analogy, different steel grades and specification are calculated one by one, compares one by one, obtain every time institute of mm finishing mill unit The peak power needed, as shown in table 2.

The peak power that the mm finishing mill unit that table 2 uses this patent to calculate needs designs with rated power

Mm finishing mill unit	Maximum rolling force kN	Roll speed m/s	Rotating speed r/min	Maximum rolling power kW	Design rated power kW
						14#	490	10.4	618.5	1156.0	1200
15#	581	11.1	650.2	1470.2	1500
						16#	518	11.5	690.9	1151.1,	1200
17#	570	12.1	716.2	1403.8	1500
						18#	475	16.3	972.8	1150.9	1200
19#	824	16.5	980.8	1620.0	1700

The peak power that the mm finishing mill unit that table 3 Ekelund formula calculates needs designs with rated power

From table 2,3 and Fig. 7, the maximum rolling power gap of two kinds of method calculating is very big, according to both Result of calculation, the most newly-built two rolling lines, go into operation after running, in advance according to traditional E kelund formula result of calculation The power of motor distribution of newly-built rolling line cannot meet design requirement；The product line dependence this patent algorithm that later stage is newly-built, newly After producing line operation, this patent algorithm is very accurate, meets low temperature process requirement well, some passage does not occur The problem that power of motor transships or surplus is excessive.

Claims (1)

1. a Bar Wire Product pass low temperature controlled rolling power of motor sharing of load method for designing, it is characterised in that processing step And the technical parameter of control is as follows:

(1) is produced from line product mix location in design: first, it is settled that produce steel grade and the minimum temperature requirement of rolling involved by line, Completing the design of different size pass parameters, the steel grade selecting resistance of deformation maximum carries out subsequent calculations: its rolling temperature is wanted Ask 750-800 DEG C, carbon equivalent C_eq>=0.54%, mill speed: bar 15-20m/s, wire rod 110-150m/s；

(2) resistance of deformation of steel grade is measured: use single pass compression to measure on Gleeble3000 hot modeling test machine, Specimen size is Φ 6mm × 15mm, 15 altogether；Austenitizing temperature 1250 DEG C, is incubated 5min, deformation temperature Degree 1073K, 1173K, 1223K, 1273K, 1323K respectively；Strain rate takes 0.1s respectively^-1、1s^-1、10 s^-1, engineering strain 50%, compress rear water-cooled, make strain stress curve；

(3) every time the operation of rolling under the actual pass of employing DEFORM finite element software simulation:

Thermal simulation resulting materials strain stress curve is input in newly-built material depot DEFORM；

Utilize Pro/Engineer WildFire to set up rolled piece, roll 3-D geometric model, generate stl file；

Utilize DEFORM to import 3-D geometric model, set up rolling geometric model, carry out stress and strain model；

Utilize rolling schedule rolling parameter as rolling model roll, the initial condition of workpiece motion s；

The temperature field contrast correction calculated by field measurement temperature and simulation, determines that the surface between rolled piece and roll is changed Hot coefficient, guarantees the accuracy of rolling model with the accuracy of temperature calculation models；

(4) use DEFORM to simulate and calculate every time roll-force nipping, roll and throwing steel process:

Roll is considered as rigid body, and rolled piece is considered as plastic body, calculates according to rigid plasticity finite element, accurately determines that each passage is rolled The roll-force of steel process is nipped, rolls and thrown to part；

According to roll-force time changing curve, take roll-force maximum of points and calculate as milling train rated power；

(5) according to tube rolling simulation roll torque M_Z, drive moment M of a roll_KFor roll torque M_ZWith roll Moment of friction M at roller bearing_f1Sum；

M_K=M_Z+M_f1=P (a+ ρ₁)

$P=P_{m}S=P_m\frac{b_0+b_1}{2}l$

P roll-force, kN；The a roll-force arm of force, the i.e. vertical dimension of two roll centre lines of force action line-spacing, Mm,ρ₁Friction circle radius at roll bearingmm；P_mAverage unit pressure, MPa；b₀、b₁Roll forward and backward rolled piece width, mm；L contact arc length extent of horizontal projection degree, mm；D rolls Roller diameter, mm；β point of resultant force angle, °；D roll pins having diameter, mm；The friction of μ roll bearing is Number, rolling bearing μ=0.004；

(6) the power N of milling train is calculated according to roll torque_D: design motor rated power further according to overload condition；

$N_D=M_{er}\mathrm{\ω}=\frac{{\mathrm{\πM}}_{er}{n}_{er}}{30}$

$M_{er}=\frac{M_{max}}{K}$

M_erRated static torque, k Nm；M_maxMaximum moment on static load figure, k Nm；n_erMotor is specified Rotating speed, r/min；K electromotor overload coefficient, non reversible motor K=1.5～2.0.