Effect of Crown Shape of Rolls on the Distribution of Stress and Elastic Deformation for Rolling Processes

Servín, Rumualdo; Arreola, Sixtos A.; Calderón, Ismael; Pérez, Alejandro; Miguel, Sandra M. San

doi:10.3390/met9111222

Cited by 11 publications

(5 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, some lines were found to contain zero roll wear after rolling steel. Such records should be disregarded, because, even if such «outliers» are not errors, but are rare exceptional situations, they can still hardly be used [15][16][17].…”

Section: Object and Problem Statementmentioning

confidence: 99%

Big Data as a Tool for Building a Predictive Model of Mill Roll Wear

2021

View full text Add to dashboard Cite

Big data analysis is becoming a daily task for companies all over the world as well as for Russian companies. With advances in technology and reduced storage costs, companies today can collect and store large amounts of heterogeneous data. The important step of extracting knowledge and value from such data is a challenge that will ultimately be faced by all companies seeking to maintain their competitiveness and place in the market. An approach to the study of metallurgical processes using the analysis of a large array of operational control data is considered. Using the example of steel rolling production, the development of a predictive model based on processing a large array of operational control data is considered. The aim of the work is to develop a predictive model of rolling mill roll wear based on a large array of operational control data containing information about the time of filling and unloading of rolls, rolled assortment, roll material, and time during which the roll is in operation. Preliminary preparation of data for modeling was carried out, which includes the removal of outliers, uncharacteristic and random measurement results (misses), as well as data gaps. Correlation analysis of the data showed that the dimensions and grades of rolled steel sheets, as well as the material from which the rolls are made, have the greatest influence on the wear of rolling mill rolls. Based on the processing of a large array of operational control data, various predictive models of the technological process were designed. The adequacy of the models was assessed by the value of the mean square error (MSE), the coefficient of determination (R2), and the value of the Pearson correlation coefficient (R) between the calculated and experimental values of the mill roll wear. In addition, the adequacy of the models was assessed by the symmetry of the values predicted by the model relative to the straight line Ypredicted = Yactual. Linear models constructed using the least squares method and cross-validation turned out to be inadequate (the coefficient of determination R2 does not exceed 0.3) to the research object. The following regressions were built on the basis of the same operational control database: Linear Regression multivariate, Lasso multivariate, Ridge multivariate, and ElasticNet multivariate. However, these models also turned out to be inadequate to the object of the research. Testing these models for symmetry showed that, in all cases, there is an underestimation of the predicted values. Models using algorithm composition have also been built. The methods of random forest and gradient boosting are considered. Both methods were found to be adequate for the object of the research (for the random forest model, the coefficient of determination is R2 = 0.798; for the gradient boosting model, the coefficient of determination is R2 = 0.847). However, the gradient boosting algorithm is recognized as preferable thanks to its high accuracy compared with the random forest algorithm. Control data for symmetry in reference to the straight line Ypredicted = Yactual showed that, in the case of developing the random forest model, there is a tendency to underestimate the predicted values (the calculated values are located below the straight line). In the case of developing a gradient boosting model, the predicted values are located symmetrically regarding the straight line Ypredicted = Yactual. Therefore, the gradient boosting model is preferred. The predictive model of mill roll wear will allow rational use of rolls in terms of minimizing overall roll wear. Thus, the proposed model will make it possible to redistribute the existing work rolls between the stands in order to reduce the total wear of the rolls.

show abstract

Section: Object and Problem Statementmentioning

confidence: 99%

Big Data as a Tool for Building a Predictive Model of Mill Roll Wear

2021

View full text Add to dashboard Cite

show abstract

“…The contact region mesh (BUR-WR and WR-strip) is refined using 20 layers with a growth rate of 1.1; for the contact region, a bonded system (no sliding or separation between faces or edges) is implemented without penetration. The data considered for the analysis are those established for stand M-4 (Lewis United, PA, USA) of a hot rolling mill, in which the materials of the rolls are 5% Cr forged steel for BUR and nodular iron indefinite chilled double pour (ICDP) for the WR, rolling a structural steel [ 26 ].…”

Section: Methodsmentioning

confidence: 99%

Influence of Work Hardening on the Surface of Backup Rolls for a 4-High Rolling Mill Fractured during Rolling Campaign

et al. 2022

View full text Add to dashboard Cite

Backup rolls are the main tool in a four-high rolling mill; the rolling forces applied in load cells promote the fatigue of the material due to mechanical contact between backup rolls and work rolls. This work investigated the causes of recurrent failures in backup rolls, with cracking always initiated on the surface of the roll body and finishing in the main radius between neck and roll body. Aiming to find the causes of failure, visual inspection and morphology of the fracture were performed, complemented with mechanical tests of hardness on the stress concentration area, in addition to validating the results by applying the finite element method, using ANSYS Mechanical Static Structural Software. It was concluded that the fatigue crack initiated on the surface of BUR due to work hardening continued growing up over the fatigued material, creating beach marks, and finally, a fracture occurred in the main radius of BUR due to stress concentration. The work hardening is the main cause of spalling on BURs and other mechanical components exposed to mechanical contact.

show abstract

“…This mechanism, shifting, is nonexistent in the skin pass mill in question due to the type of work it performs. Due to these iterations, Servin [11] created computational models using the finite element method (FEM) to simulate rolling in quad-type laminators with crowned rolls, as shown in Table (Table 1). In this work, Servin [11], made simulations using back-up rolls (BUR) with crown positive and negative and work rolls (WR) with crown positive and negative.…”

Section: Distribution Of Rolling Loadmentioning

confidence: 99%

“…The rolling test was performed as model 4, where the back-up rolls are flat, and the working rolls are positively crowned (50μm). When performing the simulations, the following geometric figures reached the following geometric figures whose heat map indicates the intensity of the applied force, according to Figures (Figures3 and 4[11]).…”

mentioning

confidence: 99%

REDUçãO DA CARGA DE LAMINAçãO DE ENCRUAMENTO NO ENCRUAMENTO DO AçO SAE 1010 ATRAVéS DO COROAMENTO DOS CILINDROS DE TRABALHO

Pereira

2023

ABM Proceedings

View full text Add to dashboard Cite

This paper brings an approach related to the reduction of the rolling load to perform the strain hardening of rolled strips through the change of shape of the working rolls by the implementation of a crown through the process of cylinder grind. To carry out the study, strips of 2.25mm thick and 1200mm wide SAE 1010 steel were skin rolling while the intended strain hardening was 0.8%. Skin pass occurred in a four-high strip mill that has bending and tilting controls. The rolling whose work was carried out is an integrated rolling and the steel strips used for this study were manufactured by the unit itself. The cold rolling of this unit until then worked with flat rolls (without crown), thus, the data obtained in the test rolling were compared with already known data and there was a significant change in terms of force required to generate the same degree of strain hardening of the material.

show abstract

Effect of Crown Shape of Rolls on the Distribution of Stress and Elastic Deformation for Rolling Processes

Cited by 11 publications

References 19 publications

Big Data as a Tool for Building a Predictive Model of Mill Roll Wear

Big Data as a Tool for Building a Predictive Model of Mill Roll Wear

Influence of Work Hardening on the Surface of Backup Rolls for a 4-High Rolling Mill Fractured during Rolling Campaign

REDUçãO DA CARGA DE LAMINAçãO DE ENCRUAMENTO NO ENCRUAMENTO DO AçO SAE 1010 ATRAVéS DO COROAMENTO DOS CILINDROS DE TRABALHO

Contact Info

Product

Resources

About