1250mm 20 Hi Reversible Cold Rolling Mill

Product Description

1250mm 20 Hi Reversible Cold Rolling Mill

1.1.1 General Information
The unit produces a pickled hot rolled coil with a thickness of1.2mm~5mm, which is rolled into a high-precision cold-rolled steel coil of 0.1mm after several passes, using a single-stand reversible four-roll UCM cold rolling mill. The work rolls are provided with positive and negative bends, the intermediate rolls are provided with positive bending rolls and twitching, and the uncoiling machine and the front and back of the frame are provided with a tension coiler, a thickness gauge, a laser speedometer, etc., which can realize large tension rolling. Guarantee high-speed and stable production of thin gauge products.

1.1.2 Characteristics of the Rolling Mill
The 125020Hi reversible cold-rolling unit is designed for a cold-rolling production line with an annual production capacity of 200,000 tons and a single-bay UCM model. The acid washed hot rolled coil is rolled into a chill roll. The unit is equipped with hydraulic AGC, working roller with positive and negative bending roller and segment cooling, intermediate roller positive bending roller and moving, front and rear double X-ray thickness gauge, double laser speedometer and other devices. Its characteristics are:

1. Uncoiler is equipped with CPC automatic centering function, which adopts EMG products from Germany, and improves the centering response speed and position control accuracy.
2. Rolling line adjustment equipment adopts stepwise wedge combination adjustment, and the roll diameter can quickly and automatically control the stepwise wedge displacement of the oil cylinder drive to the right position, realizing automatic and quick adjustment of the rolling line (companys utility model patent:  ZL201120139812.6);

1. ImportedX-ray thickness gauge is adopted, improving the thickness precision of finished strips.
2. Imported laser velocimeter is adopted to realize mass flow AGC control in combination with AGC system, with improved the yield of strips.
3. The rolling mill adopts Simens S7-400 programmable controller, DC drive adopts 6RA80 all-digit speed regulating system, and the electric system takes safety protection measures of overload protection, strip breakage protection, emergency cut-off, etc.; the unit is equipped with functions of strip tail automatic deceleration, accurate stopping and multi-point stopping; coiler is equipped with functions of cycle memory, strip length calculation, and jaw accurate positioning.
4. AGC automatic system adopts S7-400+FM458 structure, which makes the utmost use of the controller and matches the quick response of the high-speed rolling mill.
5. In the second-level automation controlled by AGC, rolling schedule is further improved.
6. All key components and parts of hydraulic system adopt import components and parts, which improves system reliability.
7. Hydraulic AGC system is equipped with advanced functions of constant roll gap control, constant roll force control, constant thickness control, mass flow control, thickness precontrol, tension/speed automatic control, etc.

1. Rolling mill specification:F 1450/F400 1650mm
2. Max rolling pressure: 22000 KN
3. Max rolling torque:135 KN.m
4. Max threading speed: 30m/min
5. Max uncoiling speed: 650m/min
6. Max rolling speed:1500m/min
7. Uncoiling tension: 83 KN
8. Coiling tension: 200~20 KN  (I gear V＜900  m/min)

1. Max coiling speed: 1550m/min
2. Single side bending force of the work roll(positive/negative): 625/420  KN
3. Work roll size:   F400～F3651750  mm

1. Support roll size:F1450~F13301650 mm

1. ≈55  t(lower support roll)
2. Max mounting hardware weight:≈100  t(housing)
3. Outline dimension of the Unit (length x width x height): ≈23x32x11  m  

1. Drive system of main rolling mill, uncoiler and coiler adopts Siemens 6RA80 all-digit DC speed regulation, thyristor power supply and unit PLC control.  
2. The basic automation system of the unit is composed of Siemens S7-400 PLC as the master controller and the corresponding remote I/O(ET-200M), which controls the rolling line and the operation of auxiliary equipment.
3. AGC is a FM458+1.5 level automatic thickness control system with full hydraulic screw-up. It is equipped with control functions of total travel mass flow control, constant roll gap control, constant roll force control, adjustment control, automatic prepressing control, thickness precontrol AGC, thickness monitor AGC, tension/speed AGC, acceleration and deceleration AGC compensation control, roller eccentricity compensation, etc., and it is also equipped with process management functions of rolling process database, data presentation and operating control, product quality tracing, automatic recording of high-speed rolling data, automatic report generation, failure warning, and recording etc.
4.  The rolling mill has adjustment means such as reduction and deviation, working roller positive/negative bending roller and intermediate roller positive bending roller; intermediate roller traverse to set and roll segment cooling and other plate type control means.
5. Upper and lower work rolls are driven separately.
6. Uncoiler is equipped with CPC automatic centering function.

1. The electric system of the rolling mill takes safety protection measures, including overload protection, strip breakage protection, emergency cut-off, etc.; the unit is equipped with functions of strip tail automatic deceleration, accurate stopping, and multi-point stopping; coiler is equipped with functions of cycle memory, strip length calculation, jaw accurate positioning, and work roll spindle accurate positioning.
2. The unit is preset with the process parameter, and detection, presentation, alarming and stored recording for process parameters and equipment key parameters.
3. The master operational console is equipped with human-computer interface, image display of finishing rolling mill state (main parameters like uncoiling, coiling tension value, current value, speed value etc.), manual regulation, rolling process parameter setting, failure warning and report printing.
4. The rolling line elevation adopts stepwise wedge quick regulation.
5. Roll system, turning roll and oil removal roll adopt air-oil lubrication.
6. Strip surface is degreased by the combination of air purge and roller drying and degreasing.
7. Imported X-ray thickness gauge is adopted.
8. Import laser velocimeter is adopted to realize mass flow control, improve strip yield and keep encoder speed.
9. Gears adopt five-level precision 20CrMnMo alloy steel carburizing, quenching gears, and oil injection circulating lubrication.
10. Key parts like the principal axis of the coil mandrel, the fanlike segment and the hollow shaft adopt 34CrNi3Mo alloy forged steel.
11. Components of low-pressure hydraulic system adopt renowned products using imported technologies; key components like the high-pressure AGC system, the bending roll and the CPC system also adopt imported products.