1 Raw Materials<\/p>\n\n\n\n
Production primarily uses high-quality scrap steel and a small amount of pig iron, strictly controlling the total residual elements Cu, Ni, Cr, and Ti to \u22640.015%. High-quality lime, fluorite, and pre-melted refining slag are used as slag-forming agents. Deoxidation and alloying utilize silicon-manganese alloys, silicon-calcium alloys, and low-carbon ferromanganese to ensure controllable carbon increase and stable deoxidation.<\/p>\n\n\n\n
2 Process Flow<\/p>\n\n\n\n
A typical short-process route is adopted:<\/p>\n\n\n\n
EAF electric arc furnace primary refining \u2192 LF ladle refining \u2192 VD vacuum degassing \u2192 CCM billet continuous casting \u2192 high-speed wire rod rolling \u2192 finished product inspection and warehousing.<\/p>\n\n\n\n
The entire process is carried out in a closed and protected manner to minimize secondary oxidation and gas absorption.<\/p>\n\n\n\n
3 Key Process Controls for Each Step<\/p>\n\n\n\n
3.1 EAF Electric Arc Furnace Primary Refining Control<\/p>\n\n\n\n
The EAF process focuses on achieving rapid melting, efficient dephosphorization, high-carbon steel tapping, and stable slag blocking, creating low-oxygen, low-phosphorus, and suitable initial conditions for refining.<\/p>\n\n\n\n
Power supply is controlled in stages: high power during melting, appropriate oxygen supply for slag formation during oxidation, and prevention of over-oxidation at the final stage.<\/p>\n\n\n\n
The final carbon content is controlled at 0.72%\u20130.82%, using high carbon steel to reduce deoxidation difficulty and inclusion formation.<\/p>\n\n\n\n
The final phosphorus content is \u22640.012%, with a tapping temperature of 1620\u20131660 \u2103.<\/p>\n\n\n\n
Strict slag control is implemented during tapping to prevent slag from entering the ladle and causing sulfur and phosphorus reversion and secondary oxidation.<\/p>\n\n\n\n
3.2 LF Refining Process Control<\/p>\n\n\n\n
LF is the core process for desulfurization, deoxidation, composition fine-tuning, and inclusion modification in cord steel.<\/p>\n\n\n\n
A high-basicity refining slag system is used, with a basicity R=3.5\u20134.5, maintaining white slag\/carbide slag operation.<\/p>\n\n\n\n
Deep desulfurization is achieved to S\u22640.001%, with a minimum stable level below 0.0008%.<\/p>\n\n\n\n
Composite deoxidation is used, controlling the acid-soluble aluminum content to avoid the formation of large amounts of brittle Al\u2082O\u2083.<\/p>\n\n\n\n
Subsequent calcium treatment modifies high-melting-point inclusions into low-melting-point plastic inclusions, facilitating their flotation and removal.<\/p>\n\n\n\n
Bottom-blowing argon stirring is performed throughout the process. Strong stirring in the early stages promotes desulfurization, while soft blowing in the later stages ensures uniform composition and temperature.<\/p>\n\n\n\n
3.3 Vacuum Degassing Control<\/p>\n\n\n\n
Vacuum degassing is mainly used for degassing, hydrogen reduction, and further removal of fine inclusions.<\/p>\n\n\n\n
Vacuum degree \u226467 Pa, high vacuum maintained for 15\u201325 min, achieving deep dehydrogenation and denitrification.<\/p>\n\n\n\n
After vacuum treatment, soft argon blowing for 12\u201320 min is performed, ideally with slight movement of the molten steel surface without exposure, promoting inclusion aggregation and flotation.<\/p>\n\n\n\n
Control targets: [H]\u22642\u00d710\u207b\u2076, [N]\u226425\u00d710\u207b\u2076, T.O\u226410\u00d710\u207b\u2076.<\/p>\n\n\n\n
3.4 CCM Continuous Casting Process Control<\/p>\n\n\n\n
Continuous casting determines the surface and internal quality of the billet, with key controls focusing on segregation, porosity, cracks, and maintaining purity.<\/p>\n\n\n\n
Full-process protective casting: Long nozzle argon sealing + submerged nozzle + special protective slag to prevent secondary oxidation.<\/p>\n\n\n\n
Tundish superheat is strictly controlled at 15\u201325 \u00b0C; low superheat casting inhibits the rapid development of columnar crystals.<\/p>\n\n\n\n
Electromagnetic stirring in the crystallizer + end-of-line gentle reduction technology significantly improves central carbon segregation.<\/p>\n\n\n\n
Secondary cooling uses weak cooling and uniform water distribution, with a specific water volume of 0.6\u20130.8 L\/kg, reducing surface and subsurface cracks.<\/p>\n","protected":false},"excerpt":{"rendered":"
Research on EAF+LF+VD+CCM Short-Process Production Technology<\/p>\n","protected":false},"author":1,"featured_media":2250,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[18],"tags":[],"class_list":["post-2483","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"_links":{"self":[{"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/posts\/2483","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=2483"}],"version-history":[{"count":0,"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/posts\/2483\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/media\/2250"}],"wp:attachment":[{"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/media?parent=2483"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/categories?post=2483"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/luzixinzuonew.han-light.com\/index.php\/wp-json\/wp\/v2\/tags?post=2483"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}