scholarly journals Study on Failure in Outer Ring of Work Roll Bearing in Hot Rod Rolling Mill

Author(s):  
Sang-Min Byon ◽  
2019 ◽  
Vol 1 (1) ◽  
Author(s):  
Zhengnan Sun ◽  
Dongxiao Hou ◽  
Liang Xu ◽  
Peiming Shi

Considering the influence caused by a early single pit defect on the outer raceway of the work roll bearing, a 2-DOF plate strip rolling mill vertical vibration model with a single point weak fault on the outer raceway was established. With the practical parameters of the roughing mill of the 1780 hot continuous rolling mill, the vertical vibration characteristics of the rolling mill work roll with different rotating speed and different single pit defect area on the bearing outer raceway are analyzed by numerical simulation. It is found that with the change of the rotation speed of the work roll, different nonlinear vibration behaviors occurred, such as superharmonic resonance, main resonance, combined resonance and sub-harmonic resonance. Especially the subharmonic resonance of the work roll is more harmful than the main resonance when the work roll speed is twice the rotation speed corresponding to the first and second natural frequency of the rolling mill. This work provides a theoretical basis for further clarifying the effect caused by a early defect of the work roll bearing on the mill vibration.


2014 ◽  
Vol 989-994 ◽  
pp. 3386-3389
Author(s):  
Zhu Wen Yan ◽  
Hen An Bu ◽  
Dian Hua Zhang ◽  
Jie Sun

The influence on the shape of the strip from rolling force fluctuations has been analyzed. The combination of intermediate roll bending and work roll bending has been adopted. The principle of rolling force feed-forward control has been analyzed. The feed-forward control model has been established on the basis of neural networks. The model has been successfully applied to a rolling mill and a good effect has been achieved.


2018 ◽  
Vol 15 ◽  
pp. 59-64 ◽  
Author(s):  
Nobuki Yukawa ◽  
Eiji Abe ◽  
Shohei Fujiwara

Metals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 401
Author(s):  
Hainan He ◽  
Jian Shao ◽  
Xiaochen Wang ◽  
Quan Yang ◽  
Xiawei Feng

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.


2018 ◽  
Vol 104 (12) ◽  
pp. 722-727 ◽  
Author(s):  
Akira Yanagida ◽  
Ryuichi Ujiie ◽  
Riku Oi

2013 ◽  
Author(s):  
Lei Song ◽  
Mingang Shen ◽  
Xuebo Chen ◽  
Junsheng Wang

Author(s):  
Yves Carretta ◽  
Andrew Hunter ◽  
Romain Boman ◽  
Jean-Philippe Ponthot ◽  
Nicolas Legrand ◽  
...  

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.


2014 ◽  
Vol 14 (6) ◽  
pp. 707-714 ◽  
Author(s):  
Soma Ghosh ◽  
Pankhuri Sinha ◽  
Shivanandan Indimath ◽  
Goutam Mukhopadhyay ◽  
Sandip Bhattacharya

2011 ◽  
Vol 383-390 ◽  
pp. 4825-4830
Author(s):  
Xian Jin Shi ◽  
Di Ping Wu ◽  
Zhi Ying Gao

Vertical vibration is universal in the vertical system of rolling mill. It has a seriously bad effect on the quality of strip. Dynamic model of the vertical system plays an important role in the analysis of vertical vibration in rolling mill. On the basis of 1420mm six roller cold rolling mill, ADAMS rigid model and flexibility model are established in this paper. Contact stiffness of rollers is calculated through ansys simulation. Contact stiffness between the work-roll and strip is calculated by using theoretical methods and stiffness of mill stand is calculated by simplifying mill stand structure. Natural frequency and some amplitude-frequency response of vertical vibration are analyzed. The test results prove that the modeling method is feasible. Vibration derived from the deformation of rolls can be observed directly in the flexible model, which can’t be realized in the rigid body model. At the same time, the new method of calculating vertical system stiffness is also proved to be reasonable.


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