scholarly journals Resource-saving preparation of the 38KHGNM steel surface for heading of automobile components

2020 ◽  
Vol 157 ◽  
pp. 01006
Author(s):  
Aleksey Filippov ◽  
German Pachurin ◽  
Diana Goncharova ◽  
Gor Gevorgyan ◽  
Mariia Mukhina ◽  
...  
Keyword(s):  
Surface Defects ◽  
Metal Flow ◽  
Steel Grade ◽  
Metallographic Analysis ◽  
Rolled Stock ◽  
Resource Saving ◽  
Cold Upsetting ◽  
Automobile Components ◽  
Hot Rolled ◽  
Decarburized Layer

To produce high-quality fasteners for motor group components of automobiles it is necessary to follow the increased requirements to calibrated rolled stock in terms of surface defects. Therefore, the goal of this paper is to study the reasons, types and depth of the surface defects on the calibrated rolled stock from steel 38KHGNM Ø 12.0 mm on the basis of the metallographic analysis. Before cold upsetting, the hot-rolled products are subjected to metal flow and removal of unacceptable surface defects by means of expensive turning operation during which the screw cuts and cracks might appear. It has been defined, that the hot-rolled stock from steel, grade 38KHGNM, diameter 12.0 мм has nonuniform mechanical properties, grooves, laps and partial decarburization on the surface. The heat treatment of the rolled stock with a decarburized layer on the surface contributes to its further decarburization. Poor alignment of calibrated stock during its turning at the turning machine does not enable to completely remove the decarburized layer with minimum skinning of rolled stock. It has been shown that the use of rolled stock from steel 38KHGNM with surface defects and unreasonably high decarburized layer on the surface increases its rejection by 8% and raises the consumption of rolled stock for manufacturing of important fasteners for the motor group of automobiles.

scholarly journals Establishing the true causes of defects to ensure the quality of continuously cast billets and hot‑rolled products at all stages of the process chain at OJSC “BSW – Management Company of the Holding “BMC”

2021 ◽  
pp. 35-39
Author(s):  
A. V. Tereshchenko ◽  
I. A. Kovaleva
Keyword(s):  
Surface Defects ◽  
Mechanical Damage ◽  
Steel Grade ◽  
Cast Billet ◽  
Hot Metal ◽  
Continuously Cast Billet ◽  
Continuously Cast ◽  
Metal Products ◽  
Hot Rolled

Establishing the true causes of defects is one of the main prerequisites for improving the quality of metal products. One of the undesirable phenomena in the production of continuously cast billets, hot‑rolled products is the oxidation of hot metal in the environment with the formation of scale on its surface. Defects, which are violations of the continuity of the metal and deviations from the normal specified macro‑and microstructure, signifi antly reduce the technological plasticity of the metal in the conditions of its processing and operational stability.After hot rolling of a circle of 95 mm steel grade 30MpV4, surface defects were found in the finishing line. To study and establish the nature of surface defects from hot‑rolled blanks, as well as continuously cast blanks, samples were taken.Analyzing metallographic studies of defects and the production technology of the studied steel grade 30MnB4, it was found that the defects were formed as a result of mechanical damage to the continuously cast billet in the area of the pulling‑correct unit. The reason for the formation of the defect is the ingress of scale on the guide rollers.

scholarly journals Quantitative Evaluation of the Microstructure and Mechanical Properties of Hot Rolled 23MnB4 Steel Grade for Cold Upsetting

2017 ◽  
Vol 62 (2) ◽  
pp. 551-556 ◽  
Author(s):  
D. Kuc ◽  
J. Szala ◽  
I. Bednarczyk
Keyword(s):  
Mechanical Properties ◽  
Quantitative Analysis ◽  
Cooling Rate ◽  
Mechanical Treatment ◽  
Pearlitic Steel ◽  
Steel Grade ◽  
Cold Upsetting ◽  
Rod Rolling ◽  
Thermo Mechanical Treatment ◽  
Hot Rolled

AbstractThe article presents the results of tests of influence of the thermo-mechanical treatment parameters on the mechanical properties and microstructure of steel 23MnB4 for cold-upsetting. Measurements of the ferrite grains and pearlite colonies were conducted with the use of Met-Ilo program supplemented by additional procedures dedicated to structure analysis of ferritic-pearlitic steel. The process of rolling was conducted in simulation in semi-continuous finishing train arrangement with different temperature and cooling rate. Elaborated procedure of quantitative analysis of microstructure and conducted mechanical properties tests will be used during preparations of modified technologies of wire rod rolling to prepare products made of steel, the microstructure of which is characterised higher utility properties.

scholarly journals X-SDD: A New Benchmark for Hot Rolled Steel Strip Surface Defects Detection

Symmetry ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 706
Author(s):  
Xinglong Feng ◽  
Xianwen Gao ◽  
Ling Luo
Keyword(s):  
Surface Defect ◽  
Surface Defects ◽  
Steel Strip ◽  
Rolled Strip ◽  
Rolled Steel ◽  
Strip Surface ◽  
Hot Rolled Strip ◽  
Hot Rolled ◽  
Hot Rolled Steel ◽  
Detection Of Defects

It is important to accurately classify the defects in hot rolled steel strip since the detection of defects in hot rolled steel strip is closely related to the quality of the final product. The lack of actual hot-rolled strip defect data sets currently limits further research on the classification of hot-rolled strip defects to some extent. In real production, the convolutional neural network (CNN)-based algorithm has some difficulties, for example, the algorithm is not particularly accurate in classifying some uncommon defects. Therefore, further research is needed on how to apply deep learning to the actual detection of defects on the surface of hot rolled steel strip. In this paper, we proposed a hot rolled steel strip defect dataset called Xsteel surface defect dataset (X-SDD) which contains seven typical types of hot rolled strip defects with a total of 1360 defect images. Compared with the six defect types of the commonly used NEU surface defect database (NEU-CLS), our proposed X-SDD contains more types. Then, we adopt the newly proposed RepVGG algorithm and combine it with the spatial attention (SA) mechanism to verify the effect on the X-SDD. Finally, we apply multiple algorithms to test on our proposed X-SDD to provide the corresponding benchmarks. The test results show that our algorithm achieves an accuracy of 95.10% on the testset, which exceeds other comparable algorithms by a large margin. Meanwhile, our algorithm achieves the best results in Macro-Precision, Macro-Recall and Macro-F1-score metrics.

scholarly journals An improved Vision Transformer-based method for classifying surface defects in hot-rolled strip steel

2021 ◽  
Vol 2082 (1) ◽  
pp. 012016
Author(s):  
Xinglong Feng ◽  
Xianwen Gao ◽  
Ling Luo
Keyword(s):  
Surface Defect ◽  
Surface Defects ◽  
Steel Strip ◽  
Learning Ability ◽  
Rolled Strip ◽  
Strip Surface ◽  
Strip Steel ◽  
Hot Rolled Strip ◽  
Hot Rolled ◽  
Improved Algorithm

Abstract A new Vision Transformer(ViT) model is proposed for the classification of surface defects in hot rolled strip, optimizing the poor learning ability of the original Vision Transformer model on smaller datasets. Firstly, each module of ViT and its characteristics are analyzed; Secondly, inspired by the deep learning model VGGNet, the multilayer fully connected layer in VGGNet is introduced into the ViT model to increase its learning capability; Finally, by performing on the X-SDD hot-rolled steel strip surface defect dataset. The effect of the improved algorithm is verified by comparison experiments on the X-SDD hot-rolled strip steel surface defect dataset. The test results show that the improved algorithm achieves better results than the original model in terms of accuracy, recall, F1 score, etc. Among them, the accuracy of the improved algorithm on the test set is 5.64% higher than ViT-Base and 2.64% higher than ViT-Huge; the accuracy is 4.68% and 1.36% higher than both of them, respectively.

Investigation into Surface Defects Arising in Hot-Rolled SUP 11A Grade Spring Billets

2008 ◽  
Vol 8 (6) ◽  
pp. 492-497 ◽  
Author(s):  
Santosh Kumar ◽  
Vinod Kumar ◽  
R. K. Nandi ◽  
T. S. Suresh ◽  
Ramen Datta
Keyword(s):  
Surface Defects ◽  
Hot Rolled

Numerical simulation of slab deformation process with different reduction values in vertical rolls of mill 2000 roughing stands

2021 ◽  
Vol 77 (6) ◽  
pp. 675-681
Author(s):  
N. L. Bolobanova ◽  
E. A. Garber
Keyword(s):  
Process Model ◽  
Surface Defects ◽  
Numerical Study ◽  
Rolling Process ◽  
Rolled Stock ◽  
Metal Consumption ◽  
Wide Face ◽  
Total Reduction ◽  
Hot Rolling Mill ◽  
Deform 3D

Perfection of rolled stock production processes at continuous wide-strip hot rolling mill (CWHRM) aimed at minimization of metal consumption, is an effective mean to decrease its cost. In the process of slabs rolling at CWHRM, the metal consumption is stipulated first of all by complicated workpiece forming in roughing stands during consecutive reduction by vertical and horizontal rolls. Results of the numerical study of slab deformation with different values of reduction in vertical rolls of roughing stands of mill 2000 are presented. The implementation of rolling process model based on application of DEFORM-3D program of finiteelement analysis described for evaluation of metal shifting from the edges of slab in the direction of the middle of the width. The convergence of the simulation results with the measurements data of workpiece forming during roughing rolling at Severstal mill 2000 was experimentally confirmed. It was found that an increase of reduction in vertical rolls has no significant effect on the metal shifting from a narrow edge to a wide one. Increase the total reduction in vertical rolls leads to an unfavorable stress-strain state of the edge region and the Cockcroft–Latham criterion rises by 20–30%. It was proposed to reduce the total reduction in the vertical rolls of the roughing stands of mill 2000 down to 40–50 mm. It was shown that increase of time of slab moving from the heating furnace to the scale breaker causes growth the Cockcroft-Latham criterion and does not affect the amount of metal shifting from a narrow face to a wide one. The proposed method of simulation the process of slab deformation in the roughing group of the mill 2000 proved by results of industrial rolling can to be used for further study of the effect of rolls profiling and forming of surface defects with the provision of minimal metal shifting onto a wide face.

Texture Descriptors for Automatic Classification of Surface Defects of the Hot-Rolled Steel Strip

2021 ◽  
pp. 251-260
Author(s):  
Virginia Riego del Castillo ◽  
Lidia Sánchez-González ◽  
Alexis Gutiérrez-Fernández
Keyword(s):  
Surface Defects ◽  
Steel Strip ◽  
Automatic Classification ◽  
Rolled Steel ◽  
Hot Rolled ◽  
Hot Rolled Steel

Fast Position and Accurate Segmentation Algorithms for Detecting Surface Defects of the Thermal-State Heavy Rail Based on Machine Vision

2013 ◽  
Vol 5 (4) ◽  
pp. 40-60
Author(s):  
Xue Wang ◽  
Yiran Chen ◽  
Tao Cheng ◽  
Zhijiang Xie
Keyword(s):  
Nearest Neighbor ◽  
Surface Defects ◽  
Thermal State ◽  
Mean Shift ◽  
Sampling Point ◽  
Positioning Method ◽  
Rolled Condition ◽  
Novel Algorithms ◽  
Hot Rolled ◽  
Heavy Rail

Color imaging in the hot rolled condition provides the better reaction of heavy rail on surface defects. In this paper, it proposes a series of novel algorithms of accurate position and segmentation of surface defects of heavy rail. An image acquisition device is designed on the adjustable camera bracket with the linear array CCD, and based on the correlation among pixels at the image level, a fast positioning method is developed for searching the Region Of Interesting (ROI) of the surface defects. Using the Mean-Shift image filtering algorithm which features multi-parameter kernel function, amendments to the sampling point weights and regional search with the nearest neighbor sampling points, accurate segmentation of the identification character is easily achieved by K-means clustering. Experiments show that this algorithm for the identification of the heavy rail surface defects is proven to be more rapid in testing the inclusions, cracks and oxide skin defects with a good promotional value.

Rational reduction of hot-rolled 40X steel before cold upsetting

2008 ◽  
Vol 38 (7) ◽  
pp. 522-524 ◽  
Author(s):  
G. V. Pachurin ◽  
A. A. Filippov
Keyword(s):  
Cold Upsetting ◽  
Hot Rolled

Automated Visual Inspection of Surface Defects on Hot-Rolled Plate

2011 ◽  
Vol 201-203 ◽  
pp. 1619-1622
Author(s):  
Qiang Song
Keyword(s):  
Visual Inspection ◽  
Surface Defects ◽  
Digital Camera ◽  
Structural Defects ◽  
Rolled Plate ◽  
Inspection System ◽  
Automated Visual Inspection ◽  
Accurate Identification ◽  
Surface Defect Detection ◽  
Hot Rolled

This paper is concerned with the problem of automatic inspection of hot-rolled plate surface using machine vision. An automated visual inspection (AVI) system has been developed to take images of external hot-rolled plate surfaces and the detailed characteristics of the sensor system which include the illumination and digital camera are described. An intelligent surface defect detection paradigm based on morphology is proposed to detect structural defects on plate surfaces. The proposed method has been implemented and tested on a number of hot-rolled plate surfaces. The results suggest that the method can provide an accurate identification to the defects and can be developed into a commercial visual inspection system.

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