Technical Committee of PJSC "DSS" talked about qualitative changes and test results in the technology of ingots rolling with cooling-down.
Major changes have affected on time of ingot cooling-down. Method for heating ingots of low alloy steels has changed with the introduction of new technology that positively affects the quality of the metal surface and reduces its cost by eliminating the rectification and gas savings for heating.
"Baptism" of the new technology passed on steel grade20ÕÃÍÌ. Rejections by surface defects on bars are not found, although previously this rejection by surface defects reached 1.7%.
As for the steel grade 19ÕÍÌ, this case will be further investigated by central laboratory of facility because rejection was 6.75% of the rolled products. The main defect was cracks and hairlines.
In addition to these grades, the new technical solution is tested on production on seven grades, where there is no rejection. But the dataset is too small for a final decision.
As a result, Technical Committee decided to apply the new technology to the steel grades that have already tested the new technology, as well as in steel, close to them by their chemical composition. This will not only reduce the rejection, but also improve the competitiveness of products of PJSC "DSS".
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