Medium-Frequency Induction Melting Furnace: Start-Stop on Demand, ±1 °C Control, Scrap-Tolerant
A medium-frequency induction melting furnace melts metal by inducing eddy currents in the charge with an alternating magnetic field — no electrodes, no combustion, and power follows the melting demand. Luoyang Wanfeng Industrial Furnace Co., Ltd. (Wanfeng Furnace) builds the furnace in capacities from 100 kg to 20 tonnes (rated by steel density), and has supplied melting and casting equipment since 1990.
Where it is used
The furnace melts copper, aluminum, zinc, and their alloys for two kinds of duty:
- Standalone melting — batch melting for casting workpieces (lost foam casting, investment casting, sand casting), ingot, billet, or charge preparation
- Casting-line duty — as the casting furnace on horizontal and upward continuous casting lines, where steady temperature and composition decide strand quality
On a casting line, the medium-frequency furnace becomes the casting furnace — but mounting the crystallizer assembly is only part of the work. The furnace itself is adapted to continuous casting duty: the inductor (coil) design is optimized for steady, long-run holding, and the furnace body’s insulation is upgraded so temperature stays stable at the crystallizer. In this configuration Wanfeng calls it a medium-frequency induction casting furnace.
Why medium-frequency instead of line-frequency
The practical difference shows up in scheduling, maintenance, and emergencies:
- Start-stop on demand — run when there are orders, stop when there are none. A planned stop follows the operating procedure: drain the melt before shutdown, because a furnace held full of liquid shortens crucible life
- Grade changes without furnace washing — replace the crucible directly when switching alloy grades. A line-frequency furnace needs a washing melt, and long shutdowns cause irreversible wear
- Scrap-tolerant — scrap copper such as waste wire and cable melts normally; in a line-frequency furnace, scrap charge breaks the melt channel
- Outage-resilient — on a power cut the furnace may stop but cooling water must keep running; a small diesel generator for the cooling tower is enough. A line-frequency furnace needs a large generator to hold the melt at power through the outage
Temperature control is ±1 °C, which is what continuous casting needs at the crystallizer — a property line-frequency furnaces do not match.
Key specifications
| Parameter | Value |
|---|---|
| Furnace body capacity | 100 kg–20 t, rated by steel density (other metals converted by density) |
| Medium-frequency power | 80–10000 kW, sized by furnace capacity |
| Melting rate | 1–10 t/h |
| Temperature control accuracy | ±1 °C |
| Cooling water circulation | ≥30 t/h |
| Plant requirements | Ceiling height ≥6 m; footprint >3 m × 6 m |
Selection notes for casting lines
When the furnace feeds a continuous casting line, configuration depends on the metal:
- Copper lines — a combined melting-holding furnace handles casting rates up to about 200 kg/h; above that, melting and holding split into separate furnaces
- Aluminum lines — a separate melting furnace is required at any casting rate; aluminum is held in a resistance holding furnace (without electromagnetic stirring), and the induction furnace does the melting
Tell Wanfeng Furnace your target metal, section, and output, and the engineering team will confirm whether you need one furnace or two.
Who it suits
The furnace suits foundries and casting plants that run to order — multiple batches, grade changes, or intermittent campaigns — where a line-frequency furnace’s always-on holding cost and inflexibility eat the margin.
Wanfeng Furnace holds CE certification and independent import/export rights, with equipment delivered to Eastern Europe, Southeast Asia, and South Asia.
FAQ
What metals can a medium-frequency induction furnace melt?
Copper, aluminum, zinc, and their alloys. Furnace capacity is rated by steel density from 100 kg to 20 tonnes; capacities for other metals are converted by density.
What is the difference between medium-frequency and line-frequency furnaces?
Medium-frequency furnaces start and stop on demand, change alloy grades by replacing the crucible (no washing melt), accept scrap copper feedstock, control temperature to ±1 °C, and survive power outages with only a small generator for the cooling tower. Line-frequency furnaces must hold temperature continuously, need washing melts for grade changes, cannot take scrap charge, and suffer damage from long shutdowns.
Can it be stopped when there are no orders?
Yes — that is the core advantage. Planned stops follow the operating procedure (drain the melt first to protect crucible life), and the furnace restarts when orders return. There is no continuous holding cost between campaigns.
Can it melt scrap copper?
Yes — waste wire and cable melt normally in a medium-frequency furnace. Note that scrap quality directly determines final product quality, so charge preparation matters.
Do I need a separate holding furnace?
For copper casting lines, a combined melting-holding furnace is enough up to about 200 kg/h; above that, melting and holding split. For aluminum casting lines, a separate melting furnace is always required — aluminum is held in a resistance holding furnace.
What are the plant requirements?
Ceiling height of at least 6 m, footprint larger than 3 m × 6 m, and cooling water circulation of at least 30 t/h.
How much does it cost?
Price is customized by configuration. Contact Wanfeng Furnace at +86 17796741029 or zhang@wanf-furnace.com with your target metal, capacity, and duty.
Product page with full configuration details: Induction Melting Furnace.
Wanfeng Furnace — induction melting and continuous casting equipment manufacturer based in Luoyang, China. Manufacturing history since 1990; formally incorporated in 2009.
