Special Melting & Remelting

The Vacuum Induction Melting (VIM) process has been established as the most important primary vacuum melting technique for today´s industrial production of high performance special steels and super alloys for most demanding applications. Depending on the final application, VIM produced ingots are often used as electrodes in Electro Slag Remelting (ESR) and/or Vacuum Arc Remelting (VAR) processes.

Melting in vacuum has a long history of over 100 years, beginning in the 1920’s after induction furnaces were introduced. During the early sixties larger industrial VIM furnaces were designed for melting increasing quantities of high-temperature super alloys and ultra-high strength steels required by rapidly growing aerospace programs. The subsequent decades have led to a consolidation of the vacuum melting industry with different furnace designs and technical advances in operation for economic production of high-performance materials.

Today, the VIM process is carried out entirely under vacuum or controlled inert gas atmosphere including all operation sequences of charging, melting, alloying, sampling, temperature control, pouring and solidification.

The INTECO VIM furnace has been developed as a multi-chamber design, providing innovative advantages in terms of vacuum performance, melting procedure, casting method and plant ergonomics which enables our customers to reliably produce high end materials in a most modern and economic way.

Variations

• Single- or multi-chamber design
• Modular side charging chamber, trace alloy chamber and T&S manipulator
• Casting chamber in mould tunnel or turn table  design for ingots and barstick production
• Bottom and/or top pouring
• Casting under vacuum, inert gas and atmosphere
• Hot crucible exchange and transfer
• Separate sintering position
• Casting speed control
• Heat sizes from lab scale up to 30t

USP‘s of INTECO Design

• Modular multi-chamber design with small chamber volumes for highest operational flexibility and reliability
• Diagonal split design for melting and casting chamber for best access and safety
• Movable melt chamber bottom for open slag removal as well as accessibility for crucible cleaning, cold charging, relining and maintenance
• Highly efficient vacuum system adjustable to process needs (reduced pump-down time)
• All process related vacuum valves are of vertical design (unaffected by dirt and heat radiation)
• Shortest tundish design for reduced heat losses and risk of nozzle freezing as well as low operational costs for tundish relining
• Automated tilt pouring system for smaller sized systems
• Tailor made ergonomic design to meet customer specific requirements
• Holistic process and production management system (IMAS) including cost optimized alloy calculation

Electro Slag Remelting (ESR) is still one of the most important technologies in the production of steels and super alloys of highest demand for various applications. Starting from the very beginning when ESR was used only as a desulphurization step in the late sixties, the ESR process gained increased popularity for achieving superior ingot quality with respect to segregation level, cleanliness and solidification structure.

Nowadays, the ESR process has already reached industrial maturity and is used for the refinement and quality enhancement of ingots with a variety of different plant concepts. Due to the nature of the ESR process and its complexity, a lot of research and new developments has been carried out over the last decades, resulting in newly developed technologies, plant concepts and designs.

Based on INTECO‘s long term experience in Electro Slag Remelting and our continuous focus on further developments, a wide range of remelting technologies has been developed satisfying todays market requirements. Today, INTECO is in the position to offer tailor-made solutions with the related production technologies for all applications, meeting our customers expectations with respect to product quality and process stability.

Variations

• Short collar mould plants with retractable base plate
• Static mould plants with or without electrode exchange technology
• Combined static / collar mould plants
• Pressure ESR plants (up to 16 bar)
• ESR plants for hollow and rectangular ingot production
• Patented Electro Slag Rapid Remelting (ESRR^®) for billet production
• Labscale ESR furnace
• Large sized ESR furnaces (ingot weight up to 250t)
• Patented Current Conductive Mould (CCM^®) technology for segregation prone alloys

USP‘s of INTECO Design

• Newly developed protective gas system for lowest gas consumption (N₂, Ar)
• Coaxial high current loop to achieve superior ingot quality
• Weighing system and XY-adjustment for precise control of the remelting parameters
• In-depth process know-how and highly sophisticated process control for superior product quality
• Highest yield due to optimized starting and hot topping procedures
• Comprehensive process simulation model exclusively developed with the Montanuniversity of Leoben
• All necessary auxiliary equipment (stub welding, mould cleaning, alloy and slag dosing) available from one single supplier
• Best accessibility and easy maintainance
• Tailor made ergonomic design to meet customer specific requirements
• Holistic process and production management system (IMAS) for overall recipe management, data storage and definition of key performance parameters

The strict quality requirements of end users such as the air and space industry calls for a metallurgical refining process that enhances the product quality to the highest level. The Vacuum Arc Remelting (VAR) process has been developed in the 1950‘s with the aim of satisfying these increased demands on certain material properties of the final product.

Today, the VAR process is used for refining a broad variety of materials such as various steels as well as different nickel or cobalt base super alloys. Because the VAR process is carried out under inert conditions (i.e. vacuum) and with controlled solidification conditions, the remelted ingot is of superior cleanliness and lowest residual gas content.

Based on INTECO‘s long-term experience and know how in the field of vacuum metallurgy as well as sophisticated control systems for remelting systems, a wide range of well-proven and specialized solutions in VAR technology can be offered to our customers meeting the highest standards.

Variations

• VAR for steels, super alloys and reactive materials
• From lab-scale to 30t ingot weight and more
• Partial pressure remelting for minimization of evaporation losses
• Helium cooling system for improved heat transfer between mould wall and ingot
• Automatic adjustment controller
• Patented combined ESR/VAR concept

USP‘s of INTECO Design

• Coaxial furnace design with defined current path for highest reproducibility
• Sophisticated drip short analysis functionality (IDRIP^®)
• Horizontal XY adjustment of the electrode in the crucible for maintaining a constant gap with the possibility of automatic adjustment during the remelting process
• Optimized weighing system for accurate control of the remelting parameter
• Tailor made ergonomic design to meet customer specific requirements
• Best accessibility and easy to maintain
• Comprehensive process simulation model exclusively developed with the University of Leoben
• Holistic process and production management system (IMAS) for overall recipe management, data storage and definition of key performance parameters