Induction Melting vs Resistance Melting vs Gas Melting: Engineering Comparison for Metal Melting Applications
Table of Contents
- Quick Answer
- Comparison Overview
- Working Principle Comparison
- Key Technical Parameters
- Efficiency and Energy Cost Comparison
- Temperature Control Comparison
- Material Quality and Surface Condition
- Safety and Compliance Comparison
- Maintenance Comparison
- Total Cost of Ownership
- Engineering Selection Guide
- Common Engineering Mistakes
- Common Problems and Solutions
- Real Project Case Study
- Honest Limitations of Both Methods
- Final Recommendation
- FAQ
This engineering guide compares induction melting, resistance melting and gas melting for foundries, recycling plants, die-casting workshops, non-ferrous metal processors and metal heat-treatment factories. It explains how each melting method works, where each method performs well, and where it becomes inefficient or difficult to control. Buyers, engineers and production managers can use this comparison to select a suitable furnace for aluminum, copper, brass, steel, iron, zinc, precious metals and alloy melting based on efficiency, melting rate, metal quality, safety, emissions, maintenance and total cost of ownership.
Quick Answer
For most modern metal melting applications requiring clean operation, fast melting, accurate temperature control and lower oxidation, induction melting is usually the best engineering choice. Resistance melting is suitable for small to medium non-ferrous melting, holding, laboratory use and clean temperature-controlled processes where melting speed is not the highest priority. Gas melting is still practical where fuel is cheap, electrical capacity is limited, furnace capacity is large, or the process is simple and tolerant of oxidation and exhaust heat loss. In short, choose induction melting for productivity and quality, resistance melting for simple electric melting and holding, and gas melting for low-capital or fuel-driven large-capacity operations.
Comparison Overview
Metal melting can be achieved by several heat-generation methods, but the three most common industrial choices are induction melting, resistance melting and gas melting. Each method can melt metal, but the heat path, temperature response, energy loss, furnace structure and maintenance requirements are very different.
Induction melting uses electromagnetic induction to generate heat directly inside the metal charge. This direct heating mechanism is one of the main reasons induction furnaces are widely used in foundries and metal processing plants for steel, iron, copper, aluminum, brass, bronze, precious metals and alloy melting. Industry suppliers and technical references commonly describe induction melting as clean, efficient and well controlled because no flame or combustion gases contact the molten metal directly.
Resistance melting uses electrical resistance heating elements to generate heat, which is then transferred to the crucible or furnace chamber by radiation and convection. The metal does not usually generate heat internally; instead, it absorbs heat from the hot furnace environment or crucible wall. This method is common in small aluminum melting furnaces, precious-metal furnaces, laboratory furnaces, heat-treatment furnaces and holding furnaces.
Gas melting uses combustion of natural gas, LPG, propane, diesel or other fuel to heat the furnace chamber, crucible or metal bath. It remains popular because gas burners are simple, familiar and scalable. In regions where electricity is expensive and gas is cheap, gas melting may appear attractive. However, gas-fired furnaces lose significant heat through exhaust gases, furnace walls and door openings, and combustion can increase oxidation, dross and workplace emissions.
The best choice depends on material type, furnace capacity, local electricity price, gas price, production rhythm, emissions rules, alloy quality requirements and available maintenance skill. A furnace should not be selected only by purchase price. A low-cost furnace can become expensive if it consumes more energy, burns more metal, requires more labor, produces more dross or fails to meet environmental requirements.
Working Principle Comparison
Induction Melting Principle
An induction melting furnace consists of an induction power supply, water-cooled copper coil, crucible or refractory lining, furnace shell, cooling system and control cabinet. When alternating current flows through the copper coil, it produces an alternating magnetic field. The metal charge inside the crucible is cut by this magnetic field, generating eddy currents inside the metal. These eddy currents create heat due to electrical resistance.
For ferrous metals, magnetic effects also contribute during the early heating stage below the Curie temperature. Once the metal reaches high temperature or becomes molten, eddy-current heating remains the main heat source. The important point is that heat is generated directly inside the metal, not only transferred from outside. This gives induction melting fast response, strong power density and good temperature control.
Resistance Melting Principle
A resistance melting furnace uses electrical heating elements made from materials such as resistance alloy wire, silicon carbide, molybdenum disilicide or graphite, depending on temperature range and furnace atmosphere. When current passes through the element, electrical resistance converts electrical energy into heat. The heat is transferred to the crucible and then to the metal.
Resistance melting is indirect heating. The heating element, furnace chamber, insulation and crucible must first become hot, and then the charge absorbs heat. This gives resistance furnaces stable and clean heating, but the melting speed is usually slower than induction melting for the same useful metal output. Resistance furnaces are often excellent for holding molten aluminum, melting precious metals, controlled atmosphere applications, heat treatment and small batch melting.
Gas Melting Principle
A gas melting furnace uses burners to combust fuel with air or oxygen-enriched air. The flame heats the furnace chamber, crucible wall or metal bath by radiation, convection and conduction. In a crucible furnace, the burner heats the outside of the crucible and the crucible transfers heat to the metal. In a reverberatory furnace, the flame and hot gases heat the metal bath more directly.
Gas melting is mature and easy to understand, but the heat path is longer and less controlled. Hot exhaust gases leave the furnace and carry away energy. Flame contact, oxygen and combustion products can increase oxidation and dross, especially with aluminum, copper alloys and zinc-containing metals.
Key Technical Parameters
| Parameter | Induction Melting | Resistance Melting | Gas Melting | Engineering Impact |
|---|---|---|---|---|
| Heating Method | Electromagnetic heating inside the metal | Heating elements transfer heat to crucible/chamber | Fuel combustion heats crucible or bath | Direct heating usually gives induction faster response and better energy utilization. |
| Typical Metals | Steel, iron, aluminum, copper, brass, bronze, precious metals | Aluminum, zinc, lead, precious metals, small copper alloys | Aluminum, copper alloys, cast iron, zinc, general foundry metals | Material type and melting temperature strongly influence furnace choice. |
| Melting Speed | Fast | Medium to slow | Medium to fast depending on burner design | Fast melting improves production capacity and reduces waiting time. |
| Temperature Control | Excellent with electronic power control | Excellent for stable holding and slow heating | Moderate; affected by burner tuning and furnace atmosphere | Accurate control reduces overheating, alloy loss and quality variation. |
| Energy Efficiency | Generally high due to direct heating | Good in well-insulated electric furnaces | Often lower due to exhaust and wall losses | Efficiency affects operating cost, heat loss and workplace temperature. |
| Oxidation and Dross | Low to moderate | Low in controlled chamber | Moderate to high | Metal loss can be more expensive than energy loss in some alloys. |
| Workplace Environment | Clean, no flame | Clean, no flame | Flame, exhaust gas, combustion noise | Environmental and safety requirements increasingly favor electric heating. |
| Maintenance Focus | Coil, lining, capacitor, cooling system | Heating elements, insulation, crucible | Burners, refractory, exhaust, fuel system | Maintenance skill and spare parts availability affect uptime. |
| Automation Potential | High | High for controlled heating and holding | Moderate to high | Automated temperature and power control improves repeatability. |
| Initial Investment | Medium to high | Low to medium | Low to medium | Lowest purchase price does not always mean lowest lifetime cost. |
Efficiency and Energy Cost Comparison
Energy efficiency is often the first comparison point, but engineers should compare useful energy delivered to the molten metal, not only energy consumed at the meter or burner. Induction melting is efficient because the metal itself becomes the heat source. Resistance melting can also be efficient when the furnace is well insulated and the load is suitable. Gas melting often suffers from exhaust loss, wall loss, opening loss and incomplete heat transfer to the metal.
Many gas-fired furnaces are affected by flue-gas loss because a large amount of hot combustion product must leave the furnace. Some industry comparisons describe traditional gas-fired furnace efficiency as much lower than direct electric heating, while regenerative burners and waste heat recovery can improve performance but add complexity.
Resistance melting efficiency depends heavily on insulation quality, heating element location, crucible condition and operating practice. Electric resistance furnaces can perform well in continuous melting or holding applications, with some industrial comparisons reporting high electric furnace efficiencies in aluminum melting contexts.
However, energy cost is not only efficiency. It also depends on local electricity and gas prices. In some countries, electricity is expensive and natural gas is cheap. In other regions, electricity is increasingly available from solar, wind, hydro or low-carbon grids, making electric melting more attractive. The International Energy Agency notes that electrification of industrial heat can improve efficiency, diversify industrial energy supply and support energy security.
Practical Energy Cost Thinking
A useful engineering comparison should include:
- Energy price per kWh equivalent
- Actual furnace efficiency under production conditions
- Melting loss and dross generation
- Labor required per ton of molten metal
- Warm-up time and idle holding loss
- Maintenance cost and downtime
- Ventilation and exhaust treatment cost
- Carbon cost or emissions compliance cost
For example, if gas is cheaper than electricity but creates more dross, more oxidation and higher ventilation cost, the real cost advantage may disappear. For aluminum and copper alloys, metal loss can be a major hidden cost. Saving 1–2% metal loss may be more valuable than saving a small amount of fuel.
Temperature Control Comparison
Induction melting provides rapid electronic power control. Power can be increased, reduced or stopped quickly. This helps avoid overheating, shortens melting cycles and allows more consistent pouring temperatures. In coreless induction furnaces, electromagnetic stirring also improves bath uniformity, which helps reduce temperature gradients.
Resistance melting provides stable and gentle temperature control. It is excellent for holding furnaces, laboratory furnaces and small non-ferrous melting where the process needs steady heat rather than extremely fast melting. The furnace chamber and crucible act as a thermal buffer, which can be an advantage for holding but a disadvantage for fast response.
Gas melting temperature control is more dependent on burner condition, air-fuel ratio, flame direction, furnace pressure and operator setting. Advanced burner controls, oxygen sensors and regenerative systems can improve performance, but temperature uniformity may still be affected by flame impingement, hot spots and exhaust path.
Temperature Control Summary
| Control Requirement | Best Option | Reason |
|---|---|---|
| Fast melting with quick power response | Induction melting | Power is controlled electronically and heat is generated directly in the metal. |
| Stable holding temperature | Resistance melting | Thermal inertia and insulation provide stable temperature control. |
| Simple large furnace operation | Gas melting | Burner systems are familiar and scalable where fuel is available. |
| Low overheating risk for alloy control | Induction or resistance | Electric control is easier to automate and repeat. |
Material Quality and Surface Condition
Material quality is one of the strongest reasons to select induction melting. Because induction melting does not require open flame contact with the molten bath, oxidation and gas pickup can be lower when the process is properly managed. Induction stirring can help homogenize alloy composition and temperature. This is valuable for alloy steel, copper alloys, aluminum alloys and precious metals.
Resistance melting also provides a clean environment because there is no combustion flame. It can be used with protective atmosphere, controlled atmosphere or vacuum designs in special applications. For small batches and sensitive metals, resistance melting can produce excellent quality if the crucible and atmosphere are properly selected.
Gas melting may expose the charge or crucible to flame and combustion gases. This can increase oxidation, dross and surface contamination, especially for aluminum and copper alloys. Poor burner adjustment can create oxidizing or reducing atmospheres that affect metal quality. Gas melting can still produce acceptable castings, but it needs careful fluxing, skimming, burner control and operator discipline.
Metal Quality Considerations
- Aluminum: sensitive to oxidation and hydrogen pickup; electric melting often improves cleanliness.
- Copper and brass: zinc loss and oxidation must be controlled; overheating should be avoided.
- Steel and cast iron: induction melting is widely used for clean melting and alloy control.
- Precious metals: electric melting is preferred for cleaner operation and reduced metal loss.
- Recycled scrap: induction melting can improve process control, but scrap sorting remains critical.
Safety and Compliance Comparison
Safety requirements are becoming more important in furnace selection. Electric melting technologies remove open flames and fuel combustion from the immediate melting zone. This can improve workshop safety, reduce combustion-related hazards and simplify some ventilation requirements. However, electric furnaces still require strict electrical safety, cooling water protection and refractory management.
Induction melting has specific safety risks: water-cooled coils operate near molten metal, so cooling water leaks must be prevented; refractory lining must be monitored to avoid metal breakout; electrical systems require grounding, interlocks and trained maintenance. Modern induction furnaces include water pressure alarms, ground leakage protection, overcurrent protection, overvoltage protection, overtemperature protection and emergency stop systems.
Resistance melting has lower electromagnetic complexity but heating elements operate at high temperature. Element failure, insulation damage, crucible cracking and electrical hazards must be managed. Operators must avoid touching hot surfaces and must follow loading and unloading procedures.
Gas melting introduces fuel-related hazards, including gas leakage, flame flashback, burner explosion, carbon monoxide, nitrogen oxides, heat radiation and exhaust handling. Compliance may require combustion air supply, flue gas exhaust, burner safety valves, flame detection, ventilation and emissions monitoring.
From a broader environmental perspective, the IEA reports that industry is a major contributor to energy-related CO2 emissions, which is one reason many manufacturers are evaluating electrified process heat and cleaner furnace technologies.
Maintenance Comparison
Maintenance should be evaluated according to production reality. A furnace that is cheap to buy but difficult to maintain can cause expensive downtime. Each melting method has different maintenance priorities.
Induction Melting Maintenance
- Check refractory lining wear and sintering condition.
- Inspect induction coil insulation and cooling water flow.
- Maintain power capacitors, inverter modules and electrical connections.
- Clean cooling water circuit and prevent scale blockage.
- Monitor furnace tilt system, hydraulic system and safety interlocks.
- Use lining monitoring and correct charging practice to prevent metal penetration.
Resistance Melting Maintenance
- Replace heating elements when resistance increases or elements break.
- Inspect insulation bricks, ceramic fiber and furnace chamber condition.
- Check thermocouples and temperature controllers.
- Maintain crucible condition and avoid thermal shock.
- Prevent metal spillage from damaging heating elements.
Gas Melting Maintenance
- Clean and tune burners.
- Inspect gas valves, regulators, flame sensors and ignition systems.
- Maintain refractory lining exposed to flame and thermal cycling.
- Clean flues, exhaust ducts and heat recovery systems.
- Check fuel pipelines and leak protection systems.
- Maintain combustion air blowers and pressure controls.
Total Cost of Ownership
Total cost of ownership includes far more than equipment purchase price. A complete TCO calculation should include capital cost, installation, energy, labor, melting loss, maintenance, downtime, refractory life, environmental compliance, floor space, ventilation, operator training and scrap rate.
| Cost Item | Induction Melting | Resistance Melting | Gas Melting |
|---|---|---|---|
| Initial Equipment Cost | Medium to high | Low to medium | Low to medium |
| Installation Cost | Requires electrical capacity and cooling water | Simple electrical installation for small units | Requires fuel line, exhaust and combustion safety |
| Energy Cost | Low to medium depending on electricity price | Medium; good for holding and small melting | Can be low if fuel is cheap, but efficiency losses are higher |
| Metal Loss | Usually lower with good practice | Usually low | Often higher due to oxidation and dross |
| Maintenance Cost | Electrical system, lining and cooling system | Heating elements and insulation | Burners, refractory and exhaust system |
| Environmental Cost | Lower on-site emissions | Lower on-site emissions | Higher due to combustion emissions and exhaust |
| Production Cost Stability | Good when electricity supply is stable | Good for stable production | Dependent on fuel price and emissions rules |
For high-value alloys, induction melting often wins because improved yield, lower oxidation and faster melting can offset higher equipment cost. For small low-temperature melting, resistance furnaces may be more economical. For very large simple melting in regions with low fuel cost and weak electrical infrastructure, gas melting may remain competitive.
Engineering Selection Guide
| Condition | Recommended Option | Reason |
|---|---|---|
| Need fast melting and high productivity | Induction melting | Direct electromagnetic heating provides high power density and short melting time. |
| Need precise temperature control for alloy quality | Induction melting or resistance melting | Electric power control is more repeatable than flame control. |
| Small aluminum or precious metal melting | Resistance melting or induction melting | Both provide clean heating; choice depends on speed and budget. |
| Large steel or cast iron melting | Induction melting | Widely used for ferrous foundry melting and alloy control. |
| Aluminum holding after melting | Resistance holding furnace | Stable heat input and low turbulence are suitable for holding. |
| Region has cheap natural gas but limited electricity | Gas melting | Fuel cost and electrical infrastructure may favor gas operation. |
| Strict environmental or indoor air requirements | Induction melting or resistance melting | No combustion flame at the furnace reduces local emissions. |
| Low capital budget and simple metal quality requirement | Gas melting or resistance melting | Initial investment may be lower, depending on size and configuration. |
| High-value alloy or low metal-loss requirement | Induction melting | Better control and lower oxidation can improve metal yield. |
| Labor shortage and need for automation | Induction melting | Induction systems integrate well with digital control, weighing, charging and pouring automation. |
Common Engineering Mistakes
1. Comparing Only Purchase Price
The cheapest furnace is not always the lowest-cost furnace. Energy consumption, metal loss, labor, downtime and maintenance must be included. For aluminum melting, dross loss alone can change the economic result.
2. Ignoring Local Utility Capacity
Induction and resistance furnaces need sufficient electrical supply. Before selecting an electric furnace, confirm transformer capacity, cable size, voltage stability and power factor requirements.
3. Choosing Induction Frequency Incorrectly
For induction melting, furnace frequency affects stirring, penetration, power density and melting performance. Low-frequency and medium-frequency systems are chosen according to furnace size, metal type and process requirement.
4. Using Gas Melting Without Exhaust Design
Gas furnaces require proper flue design, combustion air, ventilation and emissions control. Poor exhaust design reduces efficiency and creates safety risks.
5. Underestimating Refractory Life
All melting furnaces depend on refractory or crucible condition. Incorrect lining material, poor drying, thermal shock or careless charging can cause premature failure.
6. Not Accounting for Metal Cleanliness
If the product requires high-quality castings, oxidation, gas pickup and inclusion control become very important. Furnace choice should match quality requirements, not only melting capacity.
7. Oversizing the Furnace
A furnace that is too large for the production batch wastes energy during warm-up and holding. The best furnace size should match daily production rhythm, batch size and pouring schedule.
Common Problems and Solutions
| Problem | Likely Cause | Solution |
|---|---|---|
| High energy consumption | Poor insulation, long holding time, oversized furnace, exhaust loss or low power factor | Improve insulation, reduce idle holding, match furnace size to production and optimize controls. |
| Excessive dross in aluminum melting | Overheating, flame oxidation, dirty scrap or excessive turbulence | Improve temperature control, clean scrap, reduce flame exposure and use suitable flux practice. |
| Slow melting rate | Insufficient power, poor charge packing, low burner efficiency or weak heat transfer | Increase power, optimize charging, improve burner tuning or select induction melting. |
| Uneven bath temperature | Poor circulation, inadequate stirring or poor furnace geometry | Use induction stirring, adjust burner pattern or improve furnace design. |
| Frequent refractory failure | Wrong lining material, thermal shock, metal penetration or poor sintering | Select correct refractory, follow drying/sintering procedure and improve charging practice. |
| Heating element failure in resistance furnace | Overtemperature, metal splash, oxidation or thermal cycling | Use correct element material, protect elements and avoid metal spillage. |
| Burner instability in gas furnace | Poor air-fuel ratio, blocked nozzle, unstable gas pressure or ignition fault | Tune burner, clean nozzle, stabilize gas supply and inspect safety valves. |
| Induction furnace alarm | Water shortage, overcurrent, overvoltage, capacitor fault or coil insulation issue | Check cooling water, electrical connections, capacitor bank and coil insulation. |
Real Project Case Study
Project Background
A medium-size foundry produces aluminum and brass castings for mechanical components. The old process used gas crucible furnaces. The workshop faced four problems: high dross generation, inconsistent pouring temperature, high indoor heat, and long operator-dependent melting cycles. The management considered three options: continue with improved gas burners, install resistance melting furnaces, or switch to induction melting furnaces.
Engineering Evaluation
| Evaluation Item | Gas Furnace Upgrade | Resistance Furnace | Induction Furnace |
|---|---|---|---|
| Melting Speed | Medium | Medium to slow | Fast |
| Temperature Accuracy | Moderate | Good | Excellent |
| Dross Reduction | Limited | Good | Very good |
| Workshop Heat | High | Low to medium | Low to medium |
| Operator Skill Dependence | High | Medium | Low to medium with recipe control |
| Initial Investment | Low | Medium | Higher |
Recommended Solution
The engineering recommendation was to use an induction melting furnace for primary melting and a resistance holding furnace for stable temperature holding before casting. This combination gave fast melting, good alloy control and stable pouring temperature. Gas melting was kept only as backup for emergency production.
Engineering Result
The expected benefits included shorter melt cycle, cleaner working environment, lower dross generation, more repeatable pouring temperature and easier operator training. The final return depended on electricity price, annual production tonnage and metal yield improvement, but the quality and safety improvements were clear.
Honest Limitations of Both Methods
Limitations of Induction Melting
- Higher initial investment than many simple gas or resistance furnaces.
- Requires sufficient electrical infrastructure.
- Requires cooling water system and electrical maintenance skill.
- Refractory lining condition is critical for safety.
- Scrap must be suitable for induction melting; very large or irregular scrap may need preparation.
- Power electronics and capacitors require trained service support.
Limitations of Resistance Melting
- Melting speed is usually slower than induction melting.
- Heating elements are consumables and can fail.
- Very high-temperature or large-capacity melting may be less practical.
- Heat transfer is indirect, so response is slower.
- Metal spillage can damage heating elements and insulation.
Limitations of Gas Melting
- Lower effective efficiency in many furnace designs due to exhaust loss.
- More oxidation and dross risk, especially for non-ferrous metals.
- Requires fuel system, burner maintenance and exhaust ventilation.
- Creates combustion emissions and workplace heat.
- Temperature control is more operator-dependent unless advanced controls are used.
- Environmental compliance may increase future operating cost.
Final Recommendation
If the project requires high productivity, clean melting, accurate temperature control, lower oxidation and easier automation, induction melting is the strongest overall choice. It is especially recommended for steel, cast iron, copper alloys, aluminum alloys, precious metals and high-value alloy recycling where metal yield and quality matter.
If the project involves small-batch non-ferrous melting, laboratory melting, holding, clean heating or moderate production with a lower budget, resistance melting is a practical and stable choice. It is particularly suitable when melting speed is less important than simplicity and temperature stability.
If the project is located in an area with very low gas cost, limited electrical capacity, simple quality requirements and available exhaust infrastructure, gas melting can still be acceptable. However, the buyer should carefully calculate real energy efficiency, dross loss, ventilation cost, safety risk and emissions compliance before choosing gas as the long-term solution.
For many modern foundries, the best configuration is not one technology for everything. A practical solution may be induction melting for fast primary melting, resistance holding for stable pouring temperature, and gas only as backup or for specific low-cost applications.
FAQ
1. Which is better: induction melting, resistance melting or gas melting?
Induction melting is usually better for fast melting, clean operation, accurate control and high-quality metal. Resistance melting is better for small-batch melting and holding. Gas melting is better when fuel is cheap, electrical capacity is limited and quality requirements are not very strict.
2. Is induction melting more energy efficient than gas melting?
In many applications, yes. Induction melting heats the metal directly, while gas melting loses heat through exhaust gases and furnace walls. Actual savings depend on furnace design, energy prices and operating practice.
3. Is resistance melting the same as induction melting?
No. Resistance melting uses heating elements to heat the furnace chamber or crucible. Induction melting uses an electromagnetic field to generate heat directly inside the metal charge.
4. Which furnace is best for aluminum melting?
For clean and efficient aluminum melting, induction melting is often preferred for production melting, while resistance furnaces are good for holding or small-batch melting. Gas furnaces can be used when fuel cost is low, but oxidation and dross must be controlled.
5. Which furnace is best for steel melting?
Induction melting is widely used for steel and cast iron melting because it provides fast melting, good alloy control and clean operation.
6. Which furnace has the lowest initial cost?
Simple gas furnaces and small resistance furnaces often have lower initial cost than induction furnaces. However, lifetime cost may be higher if energy loss, metal loss and maintenance are included.
7. Which furnace has the best temperature control?
Induction and resistance furnaces usually provide better temperature control than gas furnaces because electric power can be controlled more precisely and automatically.
8. Does gas melting cause more oxidation?
Often yes, especially if the flame or combustion atmosphere contacts the metal. Oxidation depends on burner tuning, furnace design, metal type and operator practice.
9. Does induction melting need cooling water?
Yes. The induction coil and power supply require cooling water. Cooling water quality, flow and pressure are important for safe operation.
10. Does resistance melting need less maintenance?
Resistance furnaces are mechanically simple, but heating elements, insulation and crucibles still require regular maintenance and replacement.
11. Can induction melting be used for copper and brass?
Yes. Induction melting is suitable for copper, brass and bronze. Temperature control is important to reduce oxidation and zinc loss in brass.
12. Can gas melting still be a good choice?
Yes. Gas melting can be practical where natural gas or LPG is cheap, electrical supply is limited, furnace capacity is large, and the process can tolerate higher heat loss and oxidation.
13. Which furnace is best for recycling scrap metal?
Induction melting is often a strong choice for clean and controllable scrap melting, especially for sorted steel, iron, aluminum and copper scrap. Scrap quality and sorting remain very important.
14. What information is needed to select a melting furnace?
You should provide metal type, melting temperature, batch weight, hourly capacity, energy price, available power supply, fuel availability, required metal quality, pouring method and environmental requirements.
15. What is the best furnace solution for a modern foundry?
For many foundries, an induction melting furnace combined with a resistance holding furnace gives a good balance of fast melting, clean metal, stable temperature and efficient production.