Induction Melting Furnace: Complete OPDEL Range and Model Selector
OPDEL builds induction melting furnaces for gold, silver, platinum and non-ferrous metals, from 1 kg desktop units to modular industrial systems. This page lists the full range side by side so you can match a model to the charge you actually pour. If you melt 1–2 kg per cycle, look at the OPEM desktop series; at 4–15 kg, the OPUMelt series; at 20–50 kg, the tilting iD+T and OPUmelt TF units; above that, the modular OPUM ITC.
Choose by charge weight, not by annual throughput
The single most common specification error in precious-metal melting is sizing a furnace on how much metal a workshop processes in a year rather than on the largest single charge it pours. Crucible capacity is quoted per metal and per karat, because density differs: the same crucible that holds 10 kg of 24 kt gold does not hold 10 kg of platinum or of stainless steel. Read the capacity column for your metal.
Three other constraints decide the shortlist before price does:
- Supply voltage. Desktop and compact units run on 230 V single phase. Everything from 12 kW upward
needs three-phase. If you do not have three-phase at the bench, the range available to you ends at the OPUMelt 4/5 series.
- Melting temperature. 1150–1300 °C covers gold, silver and their alloys. Platinum, palladium and
stainless steel need the 2000 °C units — the “U” and “P” variants.
- Cooling. Almost every model requires an external water circuit. Only the OPEM Air is forced-air
cooled with no water loop at all.
Full model comparison
| Model | Type | Max power | Supply | Crucible capacity | Max temp | Weight | Best for |
|---|---|---|---|---|---|---|---|
| OPEM Air | Desktop, air-cooled | 2.80 kW | 230 V, 1 ph | 1 kg gold | 1300 °C | 14 kg | Bench work where no water circuit can be plumbed in |
| OPEM 1G / 2G | Desktop | 2.80 kW | 230 V, 1 ph | 1 kg / 2 kg gold | 1300 °C | 14 kg | Repair benches and small batch gold melts on a normal socket |
| OPEM 1P / 2P | Desktop, platinum | 2.80 kW | 230 V, 1 ph | 50–250 g / 200–500 g Pt | 2000 °C | 14 kg | Small platinum and palladium work |
| dBF01 bench | Bench | 1.5 kW | 230 V, 1 ph | 1.54 kg Au 24 kt | 1150 °C | 50 kg | Goldsmith benches limited to single-phase supply |
| OPUM 4G / 5G | Compact | 5.0 kW | 230 V, 1 ph | 4 kg / 5 kg gold | 1300 °C | 56 kg | Small manufacturing still on single-phase supply |
| OPUM 5U | Compact, platinum | 5.0 kW | 230 V, 1 ph | 1 kg Pt / 3 kg gold | 2000 °C | 56 kg | Adding platinum without installing three-phase |
| OPUMelt TLT-3P / 5P | Tilting head | — | 380/480 V | 4 kg / 6 kg gold; 2 kg / 3 kg Pt | 2000 °C | 15 kg | Tilting pours where a Solo 12 or 16 generator is already installed |
| OPUM 12G | Production | 12 kW | 230/380–480 V, 3 ph | 10 kg Au 24 kt | 1300 °C | 90 kg | Everyday production gold melting on three-phase |
| OPUM 12U | Production, multi-metal | 12 kW | 230/380–480 V, 3 ph | 8 kg Au; 0.9–3 kg Pt; 0.6–2 kg SS | 2000 °C | 90 kg | One machine covering gold, platinum and stainless steel |
| OPUM 16G | Production | 16 kW | 380–480 V, 3 ph | 15 kg Au 24 kt | 2000 °C | 90 kg | Higher-volume gold production |
| OPUM 16U | Production, multi-metal | 16 kW | 380–480 V, 3 ph | 10 kg Au; 1.5–5 kg Pt; 1.5–5 kg SS | 2000 °C | 90 kg | Multi-metal production at higher capacity |
| iD123 → iD18 static | Static | 3.5–15 kW | 230 V / 3×230 V / 3×400 V | 2.8–15 kg Au 750 | 1150 °C (1600 °C optional) | 63–78 kg | Continuous casting feeds and fixed-crucible pours |
| iD-2+T → iD-50+T | Tilting | 3–35 kW | 440 V, 3 ph | 2–50 kg gold | 1200 °C | 100–400 kg | Repeatable pours as batch size grows past hand handling |
| OPUmelt TF-20 | Floor-standing tilting | 20 kW / 25 kW | 380/480 V, 3 ph | 20 kg gold | 1250 °C | 350 kg | Bar and large-batch gold casting |
| OPUmelt TF-40 | Floor-standing tilting | 40 kW / 50 kW | 380/480 V, 3 ph | 40 kg gold | 1250 °C | 370 kg | Refinery-scale gold pours |
| OPUmelt TF-20U | Floor-standing, platinum | 20 kW / 25 kW | 380/480 V, 3 ph | 10 kg gold; 7 kg Pt | 2000 °C | 350 kg | Large platinum work needing automatic tilt |
| OPUM ITC | Modular industrial | — | — | 73–917 kg steel; 59–685 kg brass | — | — | Foundry and industrial charges quoted by weight |
| OPCS1-D / 2-D / 3-D | Melting + vacuum casting | 7.5–10.0 kW | 400 V, 3 ph (230 V optional) | 290 g–1.3 kg Au; 350 g–1 kg Pt | 2000 °C | 250–330 kg | Melting and vacuum casting in a single machine |
Where a cell shows an em dash, that figure is not published on the model page. Ask us and we will confirm it.
Which furnace suits which operation
Repair benches, sample melts and assay work. The OPEM desktop units melt 1–2 kg of gold on a normal 230 V single-phase socket. The OPEM Air variant needs no water circuit, which matters where plumbing a chiller into a bench is impractical. The 1P and 2P variants reach 2000 °C for small platinum work.
Small and medium jewellery manufacturing. The OPUMelt 4/5 series covers 4–5 kg of gold at 5 kW, still on single-phase supply. The TLT tilting heads pair with a Solo 12 or Solo 16 generator and reach 2000 °C, which brings platinum into range for a workshop that has not previously handled it.
Production melting and refining. The OPUMelt 12/16 series is the working centre of the range: 10–15 kg of 24 kt gold at 12–16 kW on three-phase. The “U” variants trade some gold capacity for a 2000 °C ceiling, so one machine covers gold, platinum and stainless steel.
Bar production and larger refining. The iD-2+T through iD-50+T tilting series scales to 50 kg of gold, and the OPUmelt TF floor units handle 20–40 kg with automatic tilt control for repeatable pours.
Industrial and foundry. The OPUM ITC is a modular system quoted by charge weight in steel, brass and aluminium rather than by a single model number, with lining and crucible geometry specified per capacity.
Casting in one machine. The OPCS Digital series combines induction melting with vacuum casting and an included vacuum pump, taking flasks up to 150 × 180 mm.
Static, tilting or desktop
Static furnaces hold the crucible fixed and you lift or pour from it. They are simpler mechanically, cost less to maintain, and suit continuous casting feeds and smaller charges. The iD static series runs 1150 °C as standard with a 1600 °C option using an optical pyrometer.
Tilting furnaces rotate the crucible to pour. Above roughly 10 kg this stops being a convenience and becomes a safety and consistency requirement — manually handling a crucible of molten gold at 20 kg is neither safe nor repeatable. Every OPDEL unit above 20 kg is a tilting design.
Desktop units are for charges small enough to handle by hand, where footprint and single-phase supply matter more than throughput.
Related equipment
An induction melting furnace is one step in a line. The metal it produces usually goes on to continuous casting machines for rod, wire and tube, to vacuum casting machines for investment casting, or to tunnel casting for gold and silver bar for bullion. Cast material that needs softening goes to the heat treatment furnaces. Every induction furnace consumes graphite crucibles, and finished pieces pass through finishing equipment.
Frequently asked questions
What capacity induction melting furnace do I need?
Size on the largest single charge you pour, not on annual throughput, and read the capacity for your specific metal. The published capacities range from 1 kg of gold on the OPEM desktop units to 50 kg on the iD-50+T, with the OPUM ITC quoted in charge weight for steel, brass and aluminium.
Can one furnace melt gold, platinum and stainless steel?
Only the 2000 °C models. On the OPUMelt 12/16 series the “U” variants are rated for gold, platinum and stainless steel in the same machine — the OPUM 12U at 8 kg gold, 0.9–3 kg platinum or 0.6–2 kg stainless steel. The 1300 °C “G” variants are for gold and silver alloys only.
Do I need a three-phase supply?
Not for the smaller units. The OPEM desktop range, the dBF01 bench furnace and the OPUMelt 4/5 series all run on 230 V single phase. From 12 kW upward the machines require three phase, typically 380–480 V.
Does the furnace need a water chiller?
Every model except the OPEM Air requires an external water circuit, with maximum inlet water temperature of 35 °C. Minimum flow is published per model. Whether mains water can sustain that depends on your ambient conditions and duty cycle; most production installations use a closed loop.
What is the difference between the “G”, “U” and “P” model suffixes?
They indicate the temperature class and intended metal. “G” units are rated to 1300 °C for gold and silver. “U” and “P” units reach 2000 °C for platinum, palladium and stainless steel, usually at a lower crucible capacity for the same frame.
What maximum temperature do the static iD furnaces reach?
1150 °C as standard, with a 1600 °C option specified together with an optical pyrometer.
Can the tilting furnaces be automated?
The OPUmelt TF floor-standing units are supplied with automatic tilting control. The iD+T series covers 2 kg to 50 kg of gold at 440 V three phase.
How heavy are these machines?
Published weights run from 14 kg for the OPEM desktop units, through 56 kg for the OPUMelt 4/5 and 90 kg for the 12/16 series, to 350–370 kg for the OPUmelt TF floor units and up to 400 kg for the iD-50+T.
Request a quote
Tell us the metal, the karat and the largest single charge you pour, and we will confirm the model and crucible that fits. Contact OPDEL to discuss your requirement.