Secondary Metallurgy

The Secondary Metallurgy for Steelmaking is the basis for maximum plant availability, short charge-cycle times, low consumption values, and top-quality treated steel. These technologies result in high performance and productivity levels for both supplied and modernized plants, combined with impressive cost savings in secondary metallurgy. From alloy handling to degassing, desulfurization, and decarburization, secondary metallurgy is indispensable to the production of high-quality steel.

Solutions in secondary metallurgy from Primetals Technologies focus on achieving maximum efficiency and productivity through finely tuned process control and automation, ensuring efficient use of personnel and additives as well as short cycle times. Precise scaling of design parameters guarantees verifiable conformance with consumption values, while optimal plant design minimizes space costs for the vacuum pump, alloying facility, and metallurgical vessels. All components from Primetals Technologies are built to withstand the highest everyday loads, achieved through extensive standardization, years of teamwork with selected suppliers, certified output controls, and systematic quality assurance. This results in assured delivery times, high availability, and a long plant lifecycle.

Ladle Furnaces (LF)

Installation of a ladle furnace between the melting and casting areas is vital to assure quality and productivity improvements in steelmaking. Ladle furnace arrangements include single stations with fixed/swiveling gantries or with ladle cars/turrets, and twin stations with two roofs and one swiveling electrode gantry. The compact design guarantees minimum space requirement while offering easy access to the roof and for electrode replacement.

VD/VOD Plants

During vacuum treatment, the carbon, oxygen, nitrogen, hydrogen, and sulfur contents are reduced in different process steps depending on the melt composition. A vacuum alloy hopper system allows for compositional adjustments. Good homogenization and high alloy yields are characteristic features of this process. Depending on the metallurgical reactions in the ladle, a freeboard of 600-1,200 mm is required. To increase productivity, the VD system can be designed as or extended to a twin-vessel system. The VOD system is a tank degassing unit additionally equipped with an oxygen blowing lance, used for producing extra-low carbon stainless steel grades or for chemical heating of the melt in conjunction with aluminum/silicon additions.

RH Plants

The RH process is carried out in a refractory-lined vessel equipped with two snorkels immersed in the steel bath. By reducing system pressure, the melt rises into the vacuum vessel where decarburization, degassing, and other reactions occur. Lift gas injection into one snorkel initiates a circulation process, treating the whole heat quickly. Immersion of the snorkels is either by lowering the vacuum vessel or lifting the ladle. A quick-change vessel system can minimize exchange time.

VLD Plants

The VLD plant represents the ideal solution for secondary metallurgical operations for small heat sizes ranging from 5 to 20 tons. Developed through a joint research project between Primetals Technologies and Dörrenberg Edelstahl, VLD plants economically perform all process steps possible in VD and VOD plants, including special and stainless steel grades production. VLD plants operate worldwide, particularly in micromills, forging shops, and foundries.

Benefits of Secondary Metallurgy Solutions

• Maximum efficiency and productivity: achieved through finely tuned process control and automation
• Precise design parameters: ensures verifiable conformance with consumption values
• Optimal plant design: minimizes space costs for essential equipment
• High alloy yields: characteristic features of vacuum treatment processes
• Compact design: guarantees minimum space requirement and easy access for maintenance