With over 40 years of expertise in designing and manufacturing advanced industrial equipment, Opdel stands at the forefront of specialized thermal processing solutions worldwide. Our annealing tunnel furnaces are a benchmark in high-volume jewelry manufacturing, precisely engineered to meet the stringent metallurgical needs of gold, silver, and copper.
Optimized Continuous Annealing for Multiple Applications
Our systems are built to deliver consistent performance and superior metal quality, making them ideal for a variety of applications:
Jewelry Chains: Achieve unmatched ductility and uniform crystalline structure through precise temperature control and atmospheric regulation, ensuring durability and intricate design capability.
Coin Blanks: Enhance structural integrity by normalizing molecular composition, preventing cracking or warping during striking, and achieving flawless surface finishes.
Rectangular Plates & Wires: Relieve internal stresses for improved cold working and forming, minimizing fracture risks and enabling complex shaping.
Engineered for Reliability and Longevity
Opdel annealing furnaces are renowned for their robust construction, designed for non-stop, multi-decade operation in demanding mass production environments. They guarantee consistent throughput, optimal process control, and exceptional energy efficiency for clients across the globe.
Whether you are in precious metal refining, jewelry production, or coin minting, Delmer Group provides state-of-the-art annealing solutions that ensure precision, productivity, and profitability.
Our furnaces are equipped with 2 heating chambers which work with separated heating zones with separate setting of temperatures. Furnaces are made by a tubular frame and panels with louvres for air exchange. Tubular system makes general maintenance interventions easier. Resistence and special refractory insulating panels, with high thermal features, make up heating muffles. Special stainless steel heating chamber can withstand strong temperature changes. Internal sliding blocks avoid wear and tear of chamber because of belt running. Cooling chamber is cooled by water. A flange keeps together the chambers and a nozzle on it let gas go inside. Two burners, placed in front of both extremities of tunnel, avoid entrance of oxygen and improves de-oxidation.
Optional :
- Chain guide
- Hydrogen Nitrogen Mixer
- Ammonia filter
- Ammonia pressare regulator
- Nitrogen pressare regulator
- Hydrogen pressare regulator
- Ammonia dissociator
- (Braket values are optional)
| Model | bD 020 | bD 030 | bD 040 | bD 050 | |
| Size | mm kg |
700 x 3050 x1530 390 (450 with diss.) |
700 x 4030 x1530 580 (640 with diss.) |
700 x 44600 x1530 600 (660 with diss.) |
700 x 5030 x1530 660 (520 with diss.) |
| Voltage | V | 3 x 400V (3x230V Optional) | |||
| Power | Inv | 11.5 13.5 (with diss.) |
13.3 15.8 (with diss.) |
16.8 19.3 (with diss.) |
20.3 22.8 (with diss.) |
| T Max | C° | 950 (1100 Optional) | |||
| Chamber Dimension |
mm | 80 x 40 100 x 50 |
80 x 40 100 x 50 |
80 x 40 100 x 50 |
80 x 40 100 x 50 |
| Length Heading Zone | mm | 600 | 800 | 1000 | 1200 |
| n°zone | 1 | 2 | 2 | 2 | |
| Cooling Chamber | mm | 985 | 1600 | 1600 | 1800 |
| Reducing atmosphere |
I/min | N+3H 10-20 |
N+3H 10-20 |
N+3H 10-20 |
N+3H 10-20 |
| Accessories Optional | |||||
| NH3 Dissociator | Only In Order Face 60 kg -2.5 kw |
||||
| Chain Loader | 0 | ||||
| Belt Types | |||||
| Model | bD 020 | bD 030 | bD 040 | bD 050 | |
| Size | mm kg |
700 x 3050 x1530 390 (450 with diss.) |
700 x 4030 x1530 580 (640 with diss.) |
700 x 44600 x1530 600 (660 with diss.) |
700 x 5030 x1530 660 (520 with diss.) |
| Voltage | V | 3 x 400V (3x230V Optional) | |||
| Power | Inv | 11.5 13.5 (with diss.) |
13.3 15.8 (with diss.) |
16.8 19.3 (with diss.) |
20.3 22.8 (with diss.) |
| T Max | C° | 950 (1100 Optional) | |||
| Chamber Dimension |
mm | 80 x 40 100 x 50 |
80 x 40 100 x 50 |
80 x 40 100 x 50 |
80 x 40 100 x 50 |
| Length Heading Zone | mm | 600 | 800 | 1000 | 1200 |
| n°zone | 1 | 2 | 2 | 2 | |
| Cooling Chamber | mm | 985 | 1600 | 1600 | 1800 |
| Reducing atmosphere |
I/min | N+3H 10-20 |
N+3H 10-20 |
N+3H 10-20 |
N+3H 10-20 |
| Accessories Optional | |||||
| NH3 Dissociator | Only In Order Face 60 kg -2.5 kw |
||||
| Chain Loader | 0 | ||||
| Belt Types | |||||
| Model | bD 020 | bD 030 | bD 040 | bD 050 | |
| Size | mm kg |
700 x 3050 x1530 390 (450 with diss.) |
700 x 4030 x1530 580 (640 with diss.) |
700 x 44600 x1530 600 (660 with diss.) |
700 x 5030 x1530 660 (520 with diss.) |
| Voltage | V | 3 x 400V (3x230V Optional) | |||
| Power | Inv | 11.5 13.5 (with diss.) |
13.3 15.8 (with diss.) |
16.8 19.3 (with diss.) |
20.3 22.8 (with diss.) |
| T Max | C° | 950 (1100 Optional) | |||
| Chamber Dimension |
mm | 80 x 40 100 x 50 |
80 x 40 100 x 50 |
80 x 40 100 x 50 |
80 x 40 100 x 50 |
| Length Heading Zone | mm | 600 | 800 | 1000 | 1200 |
| n°zone | 1 | 2 | 2 | 2 | |
| Cooling Chamber | mm | 985 | 1600 | 1600 | 1800 |
| Reducing atmosphere |
I/min | N+3H 10-20 |
N+3H 10-20 |
N+3H 10-20 |
N+3H 10-20 |
| Accessories Optional | |||||
| NH3 Dissociator | Only In Order Face 60 kg -2.5 kw |
||||
| Chain Loader | 0 | ||||
| Belt Types | |||||
Frequently Asked Questions
An annealing tunnel furnace is a continuous heat treatment system used to improve the ductility, strength, and internal structure of metals such as gold, silver, copper, and other non-ferrous alloys through controlled heating and cooling
OPDEL annealing tunnel furnaces are ideal for processing jewelry chains, coin blanks, metal wires, strips, plates, and other precision metal components in continuous production.
Dual heating chambers with independent temperature controls allow different heat treatment processes to run simultaneously, increasing productivity, process flexibility, and temperature accuracy.
The furnace operates up to 950°C as standard, with an optional maximum temperature of 1100°C for specialized applications.
The furnace uses a Nitrogen-Hydrogen (N₂ + H₂) reducing atmosphere to minimize oxidation, improve surface finish, and ensure high-quality annealing results.
These furnaces are widely used in jewelry manufacturing, precious metal refining, coin minting, wire production, and industrial metal processing.
Yes. OPDEL offers customized furnace configurations, chamber sizes, heating zones, conveyor systems, and optional accessories to meet specific production requirements.
With over 40 years of engineering expertise, OPDEL delivers reliable, energy-efficient, and precision-engineered annealing tunnel furnaces designed for continuous industrial production and superior metallurgical performance.