CN101020193A - Finishing mill capable of treating side bulge in medium width cold rolled coiled steel band - Google Patents

Abstract

The present invention belongs to the field of steel rolling technology, and is especially finishing mill capable of treating side bulge in medium width cold rolled coiled steel band. The finishing mill includes tandem mill frames arranged successively with upper and lower working rolls and upper and lower backing rolls, and the improved working rolls are curved rolls of symmetrical curve. The present invention has reasonable design, convenient operation, and raised hot rolling yield and quality.

Description

Finishing mill device capable for the treatment of side bulge in medium width cold rolled coiled steel band

Technical field

The present invention relates to a kind of steel rolling equipment, particularly the rolling device of hot rolling medium-width strip finish rolling operation belongs to technical field of steel rolling.

Background technology

One of the major defect of middle broadband cold-rolled steel coils " snare drum " is meant that steel band local crowning occurs, is strip by near part, vertically distributes along steel band, apart from strip edge edge 30～200mm." snare drum " appears at the softer steel grade of material usually, and width is 30～100mm.Make steel roll binding easily after cold rolling coil " snare drum " annealing, and also can't eliminate this defective, cause the belt steel surface injustice, can't normally use through smooth operation.At present, the method that solves " snare drum " is to adjust ways such as plate shape, raising milling train control accuracy, control hot rolling cooling water in cold rolling or hot-rolled process, but these all can not tackle the problem at its root.For a long time, " snare drum " is the thorny problem that is perplexing middle broadband cold rolling mill quality and ordinary production always, " snare drum " defective odds is higher, usually reach 10～30%, reach 80% in the time of more, many middle broadbands cold rolling mill is often taked to excise or the way of using of demoting is handled, and not only influences the lumber recovery of cold rolling coil, also, have a strong impact on the product quality and the economic benefit of enterprise because of the product quality objection.

Summary of the invention

The present invention is used to overcome the defective of prior art and a kind of finishing mill device capable for the treatment of side bulge in medium width cold rolled coiled steel band is provided, and this device is basic " snare drum " defective of eliminating by changing roll profile.

The alleged problem of the present invention is realized by following technical scheme:

A kind of finishing mill device capable for the treatment of side bulge in medium width cold rolled coiled steel band, comprise the tandem mill frame that is arranged in order in the formation, each frame is provided with upper and lower working roll and upper and lower backing roll, its special feature is: described working roll 1 is the curve roller, be that work roll surface outline line 1-1 is the curve that is symmetrically distributed with body of roll center line, described curve is determined by following formula:

$Z=\left\{\begin{array}{cc}C\left(\cos \frac{{\mathrm{\&alpha;}}_{s}y}{{3l}_s}\right)& 0\&le;y\&le;{2\mathrm{<figure-callout\; id="0"\; label="l\; s"\; filenames="A20071006159300081.png"\; state="\{\{state\}\}">l</figure-callout>}}_s\\ 0& {2l}_s<y\&le;l_w/2\end{array}\right.$

L in the formula _wBe barrel length, C value-0.020～-0.100mm, l _sBe barrel length l _w0.2～0.5 times, α _sIt is 180 °～360 °.

Above-mentioned finishing mill device capable for the treatment of side bulge in medium width cold rolled coiled steel band, the roller shoulder site surface outline line 2-1 of described backing roll 2 adopt as lower curve:

${\mathrm{\&delta;}}_{\mathrm{\&gamma;}}={\mathrm{\&delta;}}_0{\left(\frac{z}{l_z}\right)}^{\mathrm{\&alpha;}}$

δ in the formula ₀Value 0.50mm～2.00mm, l _zValue 50mm～120mm, α value 2～5.

Above-mentioned finishing mill device capable for the treatment of side bulge in medium width cold rolled coiled steel band, the roller shoulder site surface outline line 2-2 of described backing roll 2 also can adopt following two sections broken lines:

${\mathrm{\&delta;}}_{\mathrm{\&gamma;}}=\begin{array}{}\end{array}\left\{\begin{array}{cc}{k}_1\&times;z& 0\&le;z\&le;z_1\\ {\mathrm{\&delta;}}_1+{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="A20071006159300081.png,A20071006159300091.png"\; state="\{\{state\}\}">k</figure-callout>}}_2\&times;(z-z_1)& z_1<z\&le;l_z\end{array}\right.$

δ in the formula ₁Value 0.20～1.00mm, z ₁Value 40～80mm, k ₁Value 0.0020～0.0050, k ₂Value 0.0100～0.0350, l _zValue 50mm～120mm.

Above-mentioned finishing mill device capable for the treatment of side bulge in medium width cold rolled coiled steel band, described top working roll adopt curve roller, bottom working roll to adopt common plain-barreled roll or bottom working roll to adopt curve roller, top working roll to adopt common plain-barreled roll or upper and lower working roll to adopt identical curve roller.

The major defect snare drum problem of broadband cold-rolled steel coils is improved existing hot-rolled process finishing mill device in the present invention is directed to, and its each frame working roll adopts the particular curve roll shape of middle part indent; Each rack support roller adopts shoulder to form the curve roll shape of chamfering with curve or broken line.After the improvement, solve " snare drum " problem substantially, shown that through on probation this art designs is reasonable, easy to operate, can obviously reduce " snare drum " defective, improved lumber recovery, the qualification rate of hot-strip in the cold rolling process.The present invention can make full use of existing equipment, needn't use too much investment just can solve " snare drum " problem, simple, the realization easily of method, and do not influence original technological process of production.

The specific embodiment

Description of drawings

Fig. 1 is the curve synoptic diagram (not in scale) of work roll surface outline line;

Fig. 2 is the curve synoptic diagram (not in scale) of backing roll roller shoulder site surface outline line;

Fig. 3 is that backing roll roller shoulder site surface outline line is the curve synoptic diagram (not in scale) of two broken lines;

Fig. 4 is schematic diagram of the present invention (not in scale):

Fig. 5 is each breast roller position view (not in scale).

Number in the figure is expressed as follows: 1. working roll; 1-1. work roll surface outline line; 2. backing roll; 2-1. backing roll roller shoulder site surface outline line; 2-2. backing roll roller shoulder site surface outline line (during two broken lines); 3. steel band.

The specific embodiment

Referring to Fig. 4, the present invention includes and arrange 7 finishing mill F1～F7 from left to right successively, upper and lower working roll 1 and upper and lower backing roll 2 all are set on each frame, for solving steel band snare drum problem, the present invention has at first carried out optimal design to working roll body of roll axis direction contour curve, the working roll of optimizing is the particular curve roll shape of body of roll middle part indent, its roll shape is in conjunction with suitable bending roller force setting value, can improve band steel section configuration, reduce because obvious edge thickening appears in section configuration, reach the purpose of improving plate shape condition simultaneously.Referring to Fig. 1, work roll surface outline line 1-1 is the curve that is symmetrically distributed with body of roll center line, and described curve is determined by following formula:

$Z=\left\{\begin{array}{cc}C\left(\cos \frac{{\mathrm{\&alpha;}}_{s}y}{{3l}_s}\right)& 0\&le;y\&le;{2\mathrm{<figure-callout\; id="0"\; label="l\; s"\; filenames="A20071006159300081.png"\; state="\{\{state\}\}">l</figure-callout>}}_s\\ 0& {2l}_s<y\&le;l_w/2\end{array}\right.$

In the formula, C, l _s, α _sBe in conjunction with rolling scaduled, the constant definite (optimization aim is that even roller presses the power distribution indirectly, and the method for optimization is to reduce the peak value of roll gap pressure) according to optimization aim.C value-0.020 in the formula～-0.100mm, l _sBe barrel length l _w0.2～0.5 times, α _sBe 180 °～360 °, b/2 is wide half of plate, l _w/ 2 is half of barrel length, and D is a roller diameter.

After working roller was determined, need further designed the roll shape of backing roll.For pressing power indirectly, even roller distributes, improve the wearing and tearing of backing roll limit portion, improve the service life of backing roll, according to the backing roll roll shape of scene use and the typical rolling scaduled corresponding rules that provide, adopt the analysis software of band steel of hot strip mill section configuration, carry out the analog computation analysis, the shoulder roller curve of backing roll is optimized design.Referring to Fig. 2, according to the requirement of roll shape optimization aim (evenly roll gap pressure distributes), the power function curve below the roller shoulder position contour curve 2-1 of backing roll 2 adopts: ${\mathrm{\&delta;}}_{\mathrm{\&gamma;}}={\mathrm{\&delta;}}_0{\left(\frac{z}{l_z}\right)}^{\mathrm{\&alpha;}}$

δ in the formula ₀, l _z, α is the constant of determining according to optimization aim, wherein δ ₀Value 0.50mm～2.00mm, l _zValue 50mm～120mm, α value 2～5.

Referring to Fig. 3, be design and the manufacturing processing of simplifying backing roll, the chamfering that backing roll shoulder site surface outline line 2-2 also can adopt two sections broken lines to constitute, ${\mathrm{\&delta;}}_{\mathrm{\&gamma;}}=\left\{\begin{array}{cc}{k}_1\&times;\mathrm{<figure-callout\; id="0"\; label="z"\; filenames="A20071006159300081.png"\; state="\{\{state\}\}">z</figure-callout>}& 0\&le;z\&le;z_1\\ {\mathrm{\&delta;}}_1+{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="A20071006159300081.png,A20071006159300091.png"\; state="\{\{state\}\}">k</figure-callout>}}_2\&times;(z-z_1)& z_1<z\&le;{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="A20071006159300081.png,A20071006159300091.png"\; state="\{\{state\}\}">l</figure-callout>}}_2\end{array}\right.$

l _zBe the length of chamfering, δ in the formula ₁, z ₁, k ₁, k ₂It also is the constant of determining according to optimization aim.δ ₁Value 0.20～1.00mm, z ₁Value 40～80mm, k ₁Value 0.0020～0.0050, k ₂Value 0.0100～0.0350, l _zValue 50mm～120mm.

The present invention can be as required, and top working roll adopts curve roller, bottom working roll to adopt common plain-barreled roll or bottom working roll to adopt curve roller, top working roll to adopt common plain-barreled roll or upper and lower working roll to adopt identical curve roller.

The processing of above-mentioned backing roll and working roll all is accurately to process on numerically control grinder.Requirement guarantees enough cool times before the working roll grinding, eliminates the influence of residual heat roll shape, makes that machine roll shape situation is gone up in the roll shape reflection after the grinding really.After being equipped with above-mentioned roll shape,, reduce rolling milimeter number in conjunction with certain bending roller force, adjust rolling procedure, be rolled under essentially identical rolling mill practice condition, can shut out satisfactory hot rolled plate, " snare drum " degradation rate after this hot rolled plate is cold rolling can drop to below 3%.

2 embodiment below are provided

Broadband production line in certain hot rolling, mm finishing mill unit have 7 rolling mill F1～F7, working roll barrel length l _wBe 900mm, roller footpath D is 350～480mm.The backing roll barrel length is 800mm, and roller directly is 730～850mm.

First test of carrying out on this production line, F1～F7 backing roll all adopts two sections broken lines, chamfering height δ ₀Be 0.7mm, l _zBe 80mm, δ ₁, z ₁, k ₁, k ₂Be respectively 0.2mm, 55mm, 0.0036,0.020.F1～F7 bottom working roll is a plain-barreled roll, and top working roll adopts above-mentioned curve roller, and b/2 is 360mm, c, l _s, α _sSee the following form etc. parameter:

	On the F1	On the F2	On the F3	On the F4	On the F5	On the F6	On the F7
								α s(degree)	270°	270°	270°	270°	270°	270°	270°
C(mm)	-0.10	-0.10	-0.075	-0.055	-0.075	-0.065	-0.030
								l s(mm)	225	225	225	225	220	225	225

Test rolling unit such as following table:

Sequence number	Steel grade	Specification	The piece number	Remarks
					①	Q235	4.0*520	5	Hot rolling material
②	Q235	3.0*520	5	The transition material
					③	Q195L	3.5*720	37	Main stocking (cooling rolls)
④	Q195L	3.0*720	52	Main stocking (cooling rolls)
					Add up to			99

Result of the test: cold rolling material 57 volumes of part in the main stocking, through cold rolling back check snare drum descending series 1 volume, snare drum degradation rate is 1.75%.

Second test carrying out on this production line, F1～F7 backing roll all adopts two sections broken lines, chamfering height δ ₀Be 1mm, l _zBe 80mm, δ ₁, z ₁, k ₁, k ₂Be respectively 0.2mm, 55mm, 0.0036,0.0320.F1～F7 bottom working roll is a plain-barreled roll, and top working roll adopts above-mentioned curve roller, and b/2 is 360mm, c, l _s, α _sSee the following form etc. parameter:

	On the F1	On the F2	On the F3	On the F4	On the F5	On the F6	On the F7
								α s(degree)	270°	270°	270°	270°	270°	270°	270°
C(mm)	-0.09	-0.09	-0.075	-0.075	-0.045	-0.045	-0.030
								l s(mm)	225	225	225	225	220	225	225

Test rolling unit such as following table:

Sequence number	Steel grade	Specification	The piece number	Remarks
					①	Q235	4.0*520	5	Hot rolling material
②	Q235	3.0*520	5	The transition material
					③	08AL	3.5*710	47	Main stocking (cooling rolls)
④	Q195L	3.0*720	69	Main stocking (cooling rolls)
					Add up to			127

Result of the test: cold rolling material 117 volumes of main stocking are 1 volume through checking out snare drum degradation volume number after cold rolling, and snare drum degradation rate is 0.85%.

Claims (4)

1. finishing mill device capable for the treatment of side bulge in medium width cold rolled coiled steel band, comprise the tandem mill frame that is arranged in order in the formation, each frame is provided with upper and lower working roll and upper and lower backing roll, it is characterized in that: described working roll (1) is the curve roller, be that work roll surface outline line (1-1) is the curve that is symmetrically distributed with body of roll center line, described curve is determined by following formula:

$Z=\left\{\begin{array}{cc}C(\cos \frac{{\mathrm{\&alpha;}}_{s}y}{3l_s}+1)& 0\&le;y\&le;2l_s\\ 0& 2l_s<y\&le;l_w/2\end{array}\right.$

L in the formula _wBe barrel length, C value-0.020～-0.100mm, l _sBe barrel length l _w0.2～0.5 times, α _sIt is 180 °～360 °.

2. finishing mill device capable for the treatment of side bulge in medium width cold rolled coiled steel band according to claim 1 is characterized in that: the roller shoulder site surface outline line (2-1) of described backing roll (2) adopts as lower curve:

${\mathrm{\&delta;}}_r={{\mathrm{\&delta;}}_0\left(\frac{z}{l_z}\right)}^{\mathrm{\&alpha;}}$

δ in the formula ₀Value 0.50mm～2.00mm, l _zValue 50mm～120mm, α value 2～5.

3. finishing mill device capable for the treatment of side bulge in medium width cold rolled coiled steel band according to claim 1 is characterized in that: the roller shoulder site surface outline line (2-1) of described backing roll (2) adopts following two sections broken lines:

${\mathrm{\&delta;}}_r=\left\{\begin{array}{cc}{k}_1\&times;z& 0\&le;z\&le;z_1\\ {\mathrm{\&delta;}}_1+k_2\&times;(z-z_1)& z_1<z\&le;l_z\end{array}\right.$

δ in the formula ₁Value 0.20～1.00mm, Z ₁Value 40～80mm, k ₁Value 0.0020～0.0050, k ₂Value 0.0100～0.0350, l _zValue 50mm～120mm.

4. according to claim 1 or 2 or 3 described finishing mill devices capable for the treatment of side bulge in medium width cold rolled coiled steel band, it is characterized in that: described top working roll adopts curve roller, bottom working roll to adopt common plain-barreled roll or bottom working roll to adopt curve roller, top working roll to adopt common plain-barreled roll or upper and lower working roll to adopt identical curve roller.

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