{"id":2343,"date":"2026-07-23T07:55:27","date_gmt":"2026-07-23T07:55:27","guid":{"rendered":"https:\/\/hanmetallurgy.com\/?p=2343"},"modified":"2026-07-23T07:55:27","modified_gmt":"2026-07-23T07:55:27","slug":"key-points-of-steel-billet-quality-control-and-defect-prevention","status":"publish","type":"post","link":"https:\/\/luzixinzuonew.han-light.com\/index.php\/key-points-of-steel-billet-quality-control-and-defect-prevention\/","title":{"rendered":"Key Points of Steel Billet Quality Control and Defect Prevention"},"content":{"rendered":"\n

(I) Core Quality Control Indicators<\/strong><\/p>\n\n\n\n

    \n
  1. Surface Quality: No longitudinal cracks, transverse cracks, scratches, slag inclusions, excessively deep vibration marks, and rough surface.<\/li>\n\n\n\n
  2. Internal Quality: No central segregation, porosity, internal cracks, or inclusions; density meets standards.<\/li>\n\n\n\n
  3. Dimensional Accuracy: Cross-sectional dimensional deviation \u2264 \u00b11mm, rhombic deformation (squareness) \u2264 3%, straightness meets standards.<\/li>\n<\/ol>\n\n\n\n

    (II) Full-Process Control Measures<\/strong><\/p>\n\n\n\n

      \n
    1. Steel Source Control – Refining Stage: Strictly control the composition of 300 series stainless steel (Cr and Ni precisely meet standards), reduce S and P content, strengthen inclusion removal, and improve steel cleanliness. Before Casting: After the steel arrives, measure the temperature and take samples to confirm that the superheat and composition meet standards; unqualified steel is strictly prohibited from being cast.<\/li>\n\n\n\n
    2. Casting Process Control – Liquid Level Control: The liquid level in the crystallizer is stable, with fluctuations \u2264 \u00b13mm. Slag entrapment is avoided through automatic control or precise manual adjustment. – Protective Slag Management: Replenish protective slag promptly to ensure a liquid slag layer thickness of 10-15mm, and regularly clean impurities from the slag layer. Equipment Status: Monitor the operating parameters of the crystallizer, secondary cooling system, and straightening equipment in real time; adjust or shut down for maintenance immediately if abnormalities occur.<\/li>\n\n\n\n
    3. Post-Processing Control – Cutting: Ensure the cut is smooth, free of burrs and cracks; clean oxide scale promptly after cutting.Inspection: Inspect the surface quality of each piece; use ultrasonic testing for internal quality; isolate and scrap defective billets promptly. Stacking: Stack according to type, avoiding collisions and moisture to prevent surface corrosion.<\/li>\n<\/ol>\n\n\n\n

      (III) Typical Defect Prevention Plans<\/strong><\/p>\n\n\n\n

        \n
      1. Surface Longitudinal Cracks (Highly Occurs in 300 Series Stainless Steel) – Prevention: Optimize the crystallizer taper (to accommodate austenitic shrinkage), select specialized protective slag, stabilize the liquid level and casting speed, and strictly control superheat (15-25\u2103). 2. Center Segregation and Porosity – Prevention: Reduce superheat, stabilize casting speed, employ gentle reduction technology, and optimize the uniformity of secondary cooling water distribution.<\/li>\n\n\n\n
      2. Inclusion Defects – Prevention: Enhance refining (calcium treatment compatible with 300 series stainless steel), optimize tundish slag-blocking design, increase the adsorption capacity of protective slag, and prevent secondary oxidation.<\/li>\n\n\n\n
      3. Rhomboid Transformation (Square Removal) – Prevention: Employ single-taper\/double-taper crystallizers, enhance corner cooling, precisely calibrate the arc alignment of the fan-shaped segments, and control cooling differences between adjacent surfaces.<\/li>\n<\/ol>\n\n\n\n

        <\/p>\n","protected":false},"excerpt":{"rendered":"

        Steel Billet Quality Control and Defect Prevention<\/p>\n","protected":false},"author":1,"featured_media":2344,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2343","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/posts\/2343","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/comments?post=2343"}],"version-history":[{"count":0,"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/posts\/2343\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/media\/2344"}],"wp:attachment":[{"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/media?parent=2343"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/categories?post=2343"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/tags?post=2343"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}