Estimated Roll Bite Temperatures Encountered in Cold Rolling, and Their Effect in Rolling

1967 ◽  
Vol 89 (3) ◽  
pp. 471-476 ◽  
Author(s):  
H. Inhaber
Keyword(s):  
Cold Rolling ◽  
Strain Rate ◽  
Rolling Mill ◽  
Mathematical Formulation ◽  
Rolling Process ◽  
Cold Rolling Strip ◽  
Rolling Strip ◽  
Roll Bite

In modern cold rolling, strip exit velocities of the order of thousands of feet per minute are employed. Even if only moderate reductions of the strip are performed, large amounts of heat are generated due to deformation and friction. This work presents a mathematical formulation of the problem of the temperature in the roll bite as strain rate is varied (due to Cerni), as well as some calculated examples using a typical small rolling mill. The possible influence of the temperature generated on the rolling process is also considered.

Research on Shape Detecting System of Cold Rolling Strip

2011 ◽  
Vol 697-698 ◽  
pp. 525-528
Author(s):  
Li Po Yang ◽  
Bing Qiang Yu
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Shape Control ◽  
Shape Index ◽  
Cold Rolling Mill ◽  
Cold Rolling Strip ◽  
Rolling Strip ◽  
Quality Stability ◽  
Loop Shape ◽  
Shape Detecting

Comprehensive considered actual working conditions of cold rolling mill, a high precision shape detecting system of cold rolling strip was developed to meet industrial application. Consideration to both follow-up processing technology requirements, dynamic flatness standard curves could be formulated according to different rolling conditions and product specifications, and reliable shape datum were provided for close-loop shape control. This system was successfully used in Angang 1250 mm HC 6-high reversible cold rolling mill. Then the shape index and the quality stability of cold rolling strip were increased significantly, the errors between the calculated values and measured values of the total tension were less than 3%, the precision of shape detecting is 0.2 I and shape indices was within 6 I after the close-loop shape control was input.

Shape Detecting and Shape Control of Cold Rolling Strip

2011 ◽  
Vol 311-313 ◽  
pp. 902-905 ◽  
Author(s):  
Li Po Yang ◽  
Bing Qiang Yu
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Shape Control ◽  
Digital Signal ◽  
Cold Rolling Mill ◽  
Shape Deviation ◽  
Cold Rolling Strip ◽  
Rolling Strip ◽  
Loop Shape ◽  
Shape Detecting

Based on the shape detecting principle and the DSP (Digital Signal Processing) technology, a high-precision shape detecting system of cold rolling strip is developed to meet industrial application. It was successfully used in Angang 1250 mm HC 6-high reversible cold rolling mill. The precision of shape detecting was 0.2 I, the shape deviation was controlled within 6 I after the close loop shape control was input.

Thickness Indirect Measurement Method for Direct Pulling Pilot Cold Rolling Mill

2011 ◽  
Vol 189-193 ◽  
pp. 2670-2674
Author(s):  
Zhi Jie Jiao ◽  
Chun Yu He ◽  
Jian Ping Li ◽  
Xiang Hua Liu
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Measurement Method ◽  
Rolling Process ◽  
Indirect Measurement ◽  
Cold Rolling Mill ◽  
Movement Data ◽  
Program Flow ◽  
New Type ◽  
Exit Speed

Pilot cold rolling mill is the important tool for the cold rolling process researching and new steel grade development. According to the design of the new type direct pulling pilot cold rolling mill, based on the mass flow constant principle, strip exit thickness indirect measurement method is studied. During rolling, strip entry and exit speed can be calculated accurately according to the measured value of two sides’ clamps movement. Data filtering treatment is adopted and program flow chart is designed. Based on the material entry thickness measured manually, exit thickness of all passes can be measured indirectly. This thickness indirect measurement method has been applied successfully on the new type pilot cold rolling mill, and the measurement results show that this method has a good accuracy.

scholarly journals Silicon Steel Strip Profile Control Technology for Six-High Cold Rolling Mill with Small Work Roll Radius

Metals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 401
Author(s):  
Hainan He ◽  
Jian Shao ◽  
Xiaochen Wang ◽  
Quan Yang ◽  
Xiawei Feng
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Steel Strip ◽  
Work Roll ◽  
Rolling Process ◽  
Silicon Steel ◽  
Cold Rolling Mill ◽  
Strip Profile ◽  
Profile Control ◽  
Small Work

Due to the requirement of magnetic properties of silicon steel sheets, producing high-precision size strips is the main aim of the cold rolling industry. The tapered work roll shifting technique of the six-high cold rolling mill is effective in reducing the difference in transverse thickness of the strip edge, but the effective area is limited, especially for a high crown strip after the hot rolling process. The six-high mill with a small work roll size can produce a strip with higher strength and lower thickness under a smaller rolling load. At the same time, the profile of the strip can be substantially improved. By advancing a well-established analytical method, a series of simulation analyses are conducted to reveal the effectiveness of a small work roll radius for the strip profile in the six-high cold rolling process. Through the analysis of flattening deformation and deflection deformation on the load, the change rule of the strip profile produced by the work roll with a small roll diameter can be obtained. Combined with theoretical analysis and industrial experiments, it can be found that the improvement effect of the small work roll radius on the profile of the silicon strip is as significant.

scholarly journals Ultrasonic roll bite measurements in cold rolling: Contact length and strip thickness

2017 ◽  
Vol 232 (2) ◽  
pp. 179-192 ◽  
Author(s):  
Yves Carretta ◽  
Andrew Hunter ◽  
Romain Boman ◽  
Jean-Philippe Ponthot ◽  
Nicolas Legrand ◽  
...  
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Work Roll ◽  
Contact Length ◽  
Strip Thickness ◽  
Rolling Contact ◽  
Thickness Variation ◽  
Rolling Load ◽  
Process Measurements ◽  
Roll Bite

In cold rolling of thin metal strip, contact conditions between the work rolls and the strip are of great importance: roll deformations and their effect on strip thickness variation may lead to strip flatness defects and thickness inhomogeneity. To control the process, online process measurements are usually carried out; such as the rolling load, forward slip and strip tensions at each stand. Shape defects of the strip are usually evaluated after the last stand of a rolling mill thanks to a flatness measuring roll. However, none of these measurements is made within the roll bite itself due to the harsh conditions taking place in that area. This paper presents a sensor capable of monitoring strip thickness variations as well as roll bite length in situ and in real time. The sensor emits ultrasonic pulses that reflect from the interface between the roll and the strip. Both the time-of-flight of the pulses and the reflection coefficient (the ratio of the amplitude of the reflected signal to that of the incident signal) are recorded. The sensor system was incorporated into a work roll and tested on a pilot rolling mill. Measurements were taken as steel strips were rolled under several lubrication conditions. Strip thickness variation and roll-bite length obtained from the experimental data agree well with numerical results computed with a cold rolling model in the mixed lubrication regime.

Analysis of Surface Defects on Stainless Steel Cold Rolling Strip

2011 ◽  
Vol 148-149 ◽  
pp. 684-687
Author(s):  
Feng Yan ◽  
Chun Li Liu ◽  
Ke Qiang Yu
Keyword(s):  
Electron Microscopy ◽  
Stainless Steel ◽  
Cold Rolling ◽  
Surface Defects ◽  
Microscopic Analysis ◽  
Reliable Data ◽  
Cold Rolling Strip ◽  
Rolling Strip ◽  
Pattern Shape ◽  
Scanning Electron

In producing stainless steel cold rolling strip, stripe and decorative pattern shape defects occur on the surface, and influence its quality. This paper uses the spot investigation, defects microscopic analysis and scanning electron microscopy spectrometer methods in order to give a detailed analysis about surface defects, discusses the essence of defects, causes and effects process, puts forward valuable suggestions and provides reliable data for the actual production.

Nonlinear Dynamic Analysis of a Parametrically Excited Cold Rolling Mill

2014 ◽  
Vol 136 (4) ◽  
Author(s):  
Sajan Kapil ◽  
Peter Eberhard ◽  
Santosha K. Dwivedy
Keyword(s):  
Cold Rolling ◽  
Frequency Response ◽  
Governing Equation ◽  
Rolling Mill ◽  
Nonlinear Dynamic Analysis ◽  
Equation Of Motion ◽  
Horizontal Load ◽  
Cold Rolling Mill ◽  
Parametrically Excited ◽  
Roll Bite

In this work, a four high cold rolling mill is modeled as a spring-mass-damper system considering horizontally and vertically applied time-dependent forces due to the interaction between the strip and the working rolls. The effect of vibration of the moving strip on the work roll vibration is also considered for developing the governing equation of motion of the system which is found to be that of a nonlinear parametrically excited system. The governing equation of motion is solved by using the method of multiple scales to find the instability regions and frequency-response curves of the system. The critical amplitude of horizontal load in roll bite is calculated and the frequency-response is studied in detail considering the effect of various process parameters, such as velocity, thickness of strip, time delay, amplitude, and frequency of horizontal load in roll bite. This work can find application in the design and development of high speed and chatter free rolling mills.

scholarly journals Investigation and Optimization of Load Distribution for Tandem Cold Steel Strip Rolling Process

Metals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 677 ◽  
Author(s):  
Xin Jin ◽  
Changsheng Li ◽  
Yu Wang ◽  
Xiaogang Li ◽  
Yongguang Xiang ◽  
...  
Keyword(s):  
Genetic Algorithm ◽  
Cold Rolling ◽  
Prediction Model ◽  
Load Distribution ◽  
Rolling Mill ◽  
Fitness Function ◽  
Steel Strip ◽  
Rolling Process ◽  
Cold Rolling Mill ◽  
Tandem Cold Rolling

In order to improve the cold rolled steel strip flatness, the load distribution of the tandem cold rolling process is subject to investigation and optimization. The strip deformation resistance model is corrected by an artificial neural network that is trained with the actual measured data of 4500 strip coils. Based on the model, a flatness prediction model of strip steel is established in a five-stand tandem cold rolling mill, and the precision of the flatness prediction model is verified by rolling experiment data. To analyze the effect of load distribution on flatness, the flatness of stand 4 is calculated to be 7.4 IU, 10.6 IU, and 16.8 IU under three typical load distribution modes. A genetic algorithm based on the excellent flatness is proposed to optimize the load distribution further. In the genetic algorithm, the classification of flatness of stand 4 calculated by the developed flatness prediction model is taken as the fitness function, with the optimal reduction of 28.6%, 34.6%, 27.3%, and 18.6% proposed for stands 1, 2, 3, and 4, respectively. The optimal solution is applied to a 1740 mm tandem cold rolling mill, which reduce the flatness classification from 10.8 IU to 3.2 IU for a 1-mm thick steel strip.

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