What Is the Metal Melting Furnace?

The HLQ DW-MF Metal Melting Furnace is an electrically powered,medium-frequency induction system designed to melt appropriately prepared conductive metals in a compatible crucible or refractory-lined vessel. It combines a DW-MF induction power generator, resonant compensation capacitors and an induction coil surrounding the melting chamber; the published package also lists a tilting furnace for pouring. The original HLQ series includes eight models, DW-MF-15 through DW-MF-160, with listed maximum input powers of 15–160kW and a series frequency range of 1–20kHz. It is best suited to small and medium batch melting in foundries, alloy workshops, metal-recycling operations and precious-metal casting where the furnace, crucible and process are selected for the actual alloy. Listed kilograms represent reference batch capacities, not independently verified production rates.

Quick Answer: Buyer and Engineer Summary

Key Distinction: Furnace Power, Capacity and Production

Key Applications

Metal-melting duties vary by alloy family and downstream process.
The most useful configuration is the one that consistently meets
charge chemistry, safe pouring and accepted output—not simply the
highest nameplate power.

For ferrous foundry equipment, review HLQ’s
induction furnaces for iron and steel melting
to compare larger refractory-lined designs.

Application-Specific Acceptance Metrics

Suitable Materials

The DW-MF page names several metals, but it publishes explicit
capacity rows only for steel/stainless steel, gold/silver and aluminum.
Copper and bronze are valid induction-melting application categories;
however, their maximum batch weights are
not specified on this page.
Magnesium and similarly reactive metals must not be treated as
automatically suitable for an ordinary open crucible furnace.

For nonferrous melting, HLQ’s
copper induction melting furnace
page provides a different product configuration to consider.

Why Metal Properties Affect Induction Design

Working Principle

A three-phase supply energizes a DW-MF generator, which delivers
medium-frequency AC to an electrical matching network and a
water-cooled induction coil. The alternating magnetic field induces
eddy currents in conductive metal and, in some configurations,
in a conductive crucible. Resistive losses create heat; as the
charge melts, electromagnetic forces can assist stirring.
The actual inverter circuit, current paths and coil/crucible coupling
must be confirmed against the supplied drawings.

Figure 1. Induction Melting System – Functional Principle

THREE-PHASE AC POWER
         |
         v
+-----------------------+
| DW-MF POWER GENERATOR |
+-----------------------+
         |
         v
+-----------------------+
| MATCHING CAPACITORS   |
+-----------------------+
         |
         v
+-----------------------+
| WATER-COOLED COIL     |
+-----------------------+
         |
 ALTERNATING MAGNETIC FIELD
         |
         v
+-----------------------+
| METAL / CRUCIBLE      |
| EDDY CURRENTS + HEAT  |
+-----------------------+
         |
         v
 MELTING -> TEMPERATURE CHECK -> POURING

SAFETY: WATER FLOW / ELECTRICAL INTERLOCKS / LINING CHECKS

Principle by Component

Figure 2. Heating and Heat-Loss Paths

                 MEASURED ELECTRICAL INPUT (kW)
                              |
              +---------------+---------------+
              |                               |
        GENERATOR LOSSES              POWER TO LOAD CIRCUIT
                                              |
                              +---------------+---------------+
                              |                               |
                        COIL / CABLE LOSSES             CHARGE HEATING
                                                              |
                                                     +--------+--------+
                                                     |                 |
                                                MELT ENTHALPY     WALL / COVER /
                                                                  HOLDING LOSSES

NOTE: THE METAL DOES NOT RECEIVE 100% OF THE NAMEPLATE INPUT.

Technical Specifications

The tables below reproduce the published DW-MF series ratings
while separating unclear or unverified claims.
The source labels 70–550V as “Input voltage” but separately specifies
a three-phase 380V ±10% mains supply; therefore, the 70–550V field
should not be used for mains wiring or voltage selection without
clarification. The original weight and dimension rows do not explicitly
identify which assembly is being weighed or measured.

General Technical Specifications

Eight DW-MF Models and Published Reference Weights

Published Maximum Melting Ability by Material

Capacity qualification: “Or” alternatives may refer to
different crucible arrangements; they must be confirmed.
The source does not provide a copper/brass capacity table.
Maximum batch weight is not a throughput or metal-quality guarantee.
DW-MF-15 has no published steel number.

Figure 3. Published DW-MF Steel vs. Aluminum Capacity (Selected Models)

MODEL           STEEL, kg       ALUMINUM, kg

DW-MF-35        10 or 14            12
DW-MF-45        18 or 22            21
DW-MF-70        28                  30
DW-MF-90        50                  40
DW-MF-110       75                  50
DW-MF-160      100                  75

THE VALUES ARE REFERENCE BATCH CHARGES, NOT kg/h.

Recommended Model Selection

Choose the process and required batch mass first.
The table cross-references the source capacity information;
suggested models are preliminary and should be approved only after
the required crucible is confirmed and the exact alloy is tested.

For particularly contamination-sensitive precious-metal batches,
compare HLQ’s
induction gold and silver melting furnace solutions.

Model Selection by Practical Constraint

Process Workflow

A reproducible melt requires controlled charge preparation,
a correctly warmed crucible, real energy measurement and a
documented pour. Water must never enter molten metal, and
moisture or sealed scrap must be excluded from furnace charging.

Figure 4. Production Workflow and Quality Gates

IDENTIFY ALLOY + WEIGH CHARGE
              |
              v
CHECK CHARGE DRYNESS + CONTAMINANTS
              |
              v
INSPECT CRUCIBLE / LINING / COOLING / INTERLOCKS
              |
              v
LOAD CHARGE + START INDUCTION POWER
              |
              v
MELT -> CHECK kW / kWh / COOLING / BATH
              |
              v
MEASURE TEMPERATURE + CHECK CHEMISTRY
              |
              v
APPROVE DRY RECEIVING LADLE + POURING ZONE
              |
              v
CONTROLLED POUR / TILT (IF SUPPLIED)
              |
              v
RECORD MASS / YIELD / TAP-TO-TAP / kWh
              |
              v
INSPECT AND RELEASE NEXT BATCH

Process Stage, Records and Acceptance

Coil and Fixture Design

The electrical matching network, copper coil, crucible and structural support are one system. Coil turns and conductor section cannot be inferred from power alone; the cold charge, molten bath, crucible conductivity, actual load geometry and cooling arrangements must all be evaluated. The source lists a tilting furnace, but the exact tilting actuator and mechanical design are not specified for each model.

Coil, Crucible and Mechanical Design

If the intended process is repeated aluminum pouring, review HLQ’s
tilting aluminum induction melting furnace
configuration.

Illustrative Water-Side Cooling Calculation

For ordinary water,
Q(kW) = 1.163 x flow(m3/h) x temperature rise(C).
This is a water-side heat balance, not a statement of required
chiller size for any DW-MF model.

Critical Safety Verification

Control System and Automation

The source does not provide a comprehensive PLC or communication
specification. The following is an engineering configuration checklist;
only functions expressly shown on the agreed equipment schedule
should be described as standard.

Recommended Foundry Data Log

Common Problems and Solutions

Engineering Selection Guide

Evaluate each proposed furnace against the same boundary conditions:
charge mass, composition, initial temperature, tapping temperature,
actual measured electrical input, cold/hot state, yield and the
complete time between successive taps.

1. Preliminary Specific Electricity Consumption

Use measured customer data when available.
The following illustrative planning intervals
are not guaranteed DW-MF performance and vary substantially
with charge geometry, furnace losses, metal temperature
and batch size.

Energy (kWh) = charge mass (tonnes) x measured or assumed
specific electricity (kWh/t).

Example: 50kg of steel at an assumed 800kWh/t uses
0.050 x 800 = 40kWh at the chosen system boundary.

2. Estimate Energized Melting Time

Energized time (minutes) =
60 x electrical energy (kWh) / sustained mean real input power (kW).

The rated maximum input kW is not necessarily the mean kW delivered
throughout a melt. The following assumes, only for calculation,
mean input equal to 80% of the listed model maximum.

These are hypothetical energy-balance examples only; neither the
80% power factor used for mean loading nor the electrical consumption
values have been tested for these HLQ models. The calculations exclude
separate handling and pouring delays and should not be quoted as
production guarantees.

Figure 5. 100kg Steel: Mean Input Power vs. Energized Time

ASSUMED ELECTRICITY: 80kWh FOR 100kg STEEL

 MEAN REAL INPUT           CALCULATED TIME

  80kW    ##############################  60 min
 100kW    ########################        48 min
 120kW    ####################            40 min
 128kW    ###################             37.5 min
 160kW    ###############                 30 min

ILLUSTRATIVE ONLY; kWh AND REAL INPUT MUST BE MEASURED.

3. Determine Good-Metal Throughput

Gross kg/h = 60 x charge kg / tap-to-tap minutes.

Good-metal kg/h also depends on yield.
Examples below assume a 95% accepted-metal yield,
not measured performance.

4. Estimate Electricity Cost per Accepted Tonne

For budgeting,

electricity cost per accepted tonne =
measured kWh per batch x electricity tariff /
accepted mass in tonnes
.

At a hypothetical tariff of USD 0.12/kWh, 100kg of steel
requiring 80kWh and yielding 95kg acceptable metal gives
USD 9.60 per batch or approximately USD 101 per accepted tonne,
excluding labor, consumables and capital costs.

5. Verify Site Electrical Supply

For a balanced three-phase source,

S(kVA) = 1.732 x line voltage(V) x line current(A) / 1000

and

real input kW = S x true power factor
.

The examples below assume a power factor of 0.90 solely for
arithmetic; they are not DW-MF factory current specifications.

6. Factory Acceptance Test (FAT)

Advantages

Limitations

Why Choose HLQ Induction Equipment?

HLQ supplies medium-frequency induction generators and industrial melting systems. A technically useful quotation should match the DW-MF generator to the chosen metal, crucible, bath dimensions, cooling circuit and pouring arrangement. Instead of relying on a generic claim of rapid or energy-saving melting, request measured kWh per accepted ton, verified tap-to-tap productivity and a documented cooling and safety test using your own charge material.

For a related system emphasizing an electrically driven pouring arrangement, compare HLQ’s
electric induction melting furnace with a tilting device.

Customer RFQ Checklist

Core FAQs

FAQ 1. What is an induction metal melting furnace?

It is an electrically powered furnace that uses alternating magnetic fields to induce heating currents in conductive metal or in a compatible conductive crucible. The HLQ DW-MF series is intended for appropriately configured batch melting and casting preparation.

FAQ 2. Which DW-MF models are available?

The original HLQ page lists DW-MF-15, DW-MF-25, DW-MF-35, DW-MF-45, DW-MF-70, DW-MF-90, DW-MF-110 and DW-MF-160, with maximum listed electrical input ratings from 15 to 160kW.

FAQ 3. Can the furnace melt copper, brass, aluminum and steel?

These conductive metals are candidates for induction melting when the furnace, crucible and operating procedure are compatible. The original model table provides capacity figures for steel/stainless steel, aluminum and gold/silver but does not establish copper or brass batch maxima.

FAQ 4. What melting capacity is published for DW-MF-160?

The source lists 100kg of steel/stainless steel, 75kg of aluminum and 150kg or 250kg of gold/silver. The alternative precious-metal weights require exact crucible-configuration confirmation. These are reference batch sizes, not hourly production guarantees.

FAQ 5. How long does one metal-melting batch take?

The original page describes approximately 30–50 minutes on a cold start and 20–30 minutes for later warm-furnace melts. These are generic references without defined alloy, complete charge, tapping temperature or measured mean input power; actual time should be established by repeatable tests.

FAQ 6. What is the appropriate medium-frequency setting?

The published DW-MF series mentions 1–20kHz and several typical frequencies. The correct operating point depends on coil geometry, capacitance, metal resistivity, cold/hot load conditions and crucible design; not every frequency is necessarily available for every charge.

FAQ 7. How is a cooling system selected?

Calculate the heat rejected to each water circuit and confirm flow, pressure, supply temperature and required water quality with the actual equipment. A water-side heat balance is Q(kW) ≈ 1.163 × flow(m3/h) × temperature rise(°C), but this alone does not specify the complete chiller
or cooling-tower design.

FAQ 8. What should buyers include in a factory acceptance test?

Use weighed representative material and record cold/warm starts, true electrical input kW and kWh, frequency, tapping temperature, total cycle time, accepted metal yield, cooling performance and safety interlocks. If tilting is included, test loaded movement, stops and controlled pouring under approved conditions.

metal-melting-furnace-guide

Metal_Melting_Furnace_Engineering_Guide