High Purity Nitrogen Silicon Steel Stress Relief Furnace Zero Oxidation Bright Annealing

What is Silicon Steel Sheet Annealing Furnace?

Silicon steel sheet annealing furnace (also named silicon steel strip stress relief furnace) is dedicated continuous heat treatment equipment for electrical silicon steel production. It processes grain-oriented & non-oriented silicon steel strips / laminates after stamping, slitting and shearing for stress relief and recrystallization annealing.

Stamping and cutting will cause lattice distortion and internal stress inside silicon steel, which increases core loss and weakens magnetic permeability. This furnace conducts constant-temperature annealing under sealed high-purity nitrogen oxygen-free atmosphere to eliminate processing stress, homogenize grain structure and restore silicon steel’s superior low iron loss & high magnetic conductivity. Finished parts get bright oxide-free surface, becoming essential production line for transformers, motors, EV charging inductance iron cores.

This continuous mesh belt silicon steel annealing furnace consists of 4 core zones: Feeding Buffer Zone, Preheating Degreasing Zone, High-Temp Recrystallization Annealing Zone, Atmosphere Slow Cooling & Discharge Zone.

1.Feeding Buffer Zone: Stacked silicon steel laminates or steel coils are placed on high-temperature resistant mesh belt, conveyed into sealed chamber at constant speed to isolate outside air.

2.Preheating Degreasing Zone: Medium-low temperature heating removes stamping anti-rust oil and grease on silicon steel surface; waste gas is fully incinerated for eco-compliant emission.

3.High-Temp Annealing Soaking Zone: Fill 99.99% high-purity nitrogen as protective gas, precise temperature control 720~880℃. Workpieces hold constant temperature to complete grain recrystallization, fully release stamping internal stress and cut core iron loss.

4.Nitrogen Slow Cooling Zone: Parts cool down gradually under oxygen-free nitrogen atmosphere to prevent yellow oxidation. Workpieces come out with silvery bright surface without secondary polishing.

5.Auto Conveying Cycle: 310S high temp resistant mesh belt with VFD adjustable speed, supporting 24/7 non-stop annealing production with only one operator for loading & unloading.

1.310S High Temp Resistant Mesh Belt Conveying System: Driven by VFD motor, stable anti-deformation operation, suitable for thin silicon steel sheets & narrow strip coils transportation.

2.4-Zone Full Fiber Insulated Furnace Chamber: Thick alumina refractory fiber lining, low heat storage & low heat loss, overall temperature uniformity ≤±4℃.

3.High-Purity Nitrogen Atmosphere Supply System: Matched nitrogen generator with automatic pressure stabilization & flow control, slight positive pressure inside chamber to block oxygen infiltration.

4.Multi-Zone Independent PID Heating System: Ni-Cr alloy heating wires with separate zone temperature control, stable heating rate without violent temperature fluctuation.

5.Degreasing Waste Gas Incineration Purifier: Complete combustion of oil decomposition waste gas, no smoke or odor, complies with EU & US factory environmental standards.

6.PLC Touch Screen Full-Auto Control Cabinet: One-click setting for belt speed, zone temperature, nitrogen flow and soaking time; stores hundreds of silicon steel exclusive process recipes, auto alarm for over-temperature & low oxygen.

7.Double Water-Seal Isolation Doors at Inlet & Outlet: Water lock structure seals furnace atmosphere tightly, prevent air backflow and eliminate silicon steel oxidation discoloration.

1. Incorporating advanced annealing processes and proven technologies from abroad, and refined through practical application, this furnace model offers stable and reliable performance and is suitable for the annealing of motor stators.
2. This machine features a continuous-flow design, with automatic loading and unloading of workpieces by a robotic arm during the annealing process, and is equipped with automatic temperature control.
3. It offers both automatic and manual operation modes, making it suitable for batch production; it is currently the equipment with the highest production capacity.
4. Utilising fully automatic PLC intelligent control, it is simple to operate, safe and reliable.

1.Zero Oxidation & Silvery Bright Workpiece Surface: Whole process sealed under slight positive high-purity nitrogen protection, no sandblasting or polishing needed after annealing to greatly reduce post-processing cost.

2.Complete Elimination of Stamping Stress & Dramatically Reduced Core Loss: Precise constant-temperature recrystallization process recovers over 98% magnetic permeability, cuts no-load loss of transformers & motors and improves end-product energy efficiency for your buyers.

3.Ultra-Uniform Temperature Field & Stable Magnetic Consistency: Separate multi-zone temperature control brings tiny iron loss deviation for all parts in one batch, finished core yield over 99.6%.

3.24/7 Fully Automatic Mass Production & Low Labor Cost: Unattended continuous annealing line with ton-level daily processing capacity for silicon steel materials.

4.Energy Saving & Low Long-Term Operation Cost: Lightweight full fiber insulation saves over 30% power vs traditional brick furnaces; intelligent variable nitrogen flow reduces gas consumption.

5.Wide Silicon Steel Material Compatibility: Works for grain-oriented silicon steel, non-oriented silicon steel, ultra-thin silicon strips, small stamped laminates and coil continuous annealing.

6.Low Maintenance & Long Service Life: Corrosion-resistant 310S mesh belt and modular heating modules allow single damaged zone replacement without full-line shutdown.

7.Fully Customizable Design: Custom furnace inner width, total length, max annealing temperature, mesh belt load and auto loading/unloading mechanism to match different daily output demands.

1.Power Transformer Industry: Grain-oriented silicon steel core annealing for distribution transformer, dry-type transformer, high-frequency transformer.

2.Drive Motor Manufacturing: Non-oriented silicon steel stator & rotor laminates for servo motors, new energy vehicle drive motors, water pump & fan motors.

3.Power Inductor Components: Stress relief annealing for ultra-thin silicon steel sheets of EV charger inductors, high-frequency filters, switching power supplies.

4.Home Appliance Motors: Silicon steel iron cores for air conditioner compressor, refrigerator and cooling fan motors.

5.New Energy Energy Storage Equipment: Silicon steel magnetic cores for energy storage converters, PV inverters.

6.Precision Current Transformer & Relays: Bright annealing for miniature ultra-thin stamped silicon steel parts.

Q1: What atmosphere is required for silicon steel annealing?

A1: Only high-purity nitrogen (≥99.99%) is recommended. Nitrogen creates oxygen-free sealed environment to prevent silicon steel oxidation and guarantee low iron loss performance. Mixed hydrogen gas is not required for common stress relief annealing of stamped silicon steel laminates.

Q2: Can this furnace process both oriented and non-oriented silicon steel?

A2: Yes, we pre-store exclusive process programs for grain-oriented and non-oriented silicon steel inside the PLC control system. You only need to switch recipes on touch screen for different silicon steel materials.

Q3: Is the furnace size customizable for small batch pilot production and large mass production?

A3: Fully customizable. We supply small laboratory test furnaces, medium-volume standard production lines and large ton-level long continuous furnaces according to your daily processing capacity.

Q4: How long is the core component warranty period?

A4: Heating elements, PLC controller, nitrogen pressure regulating valves and mesh belt drive motor enjoy 12 months factory warranty. We provide lifetime free remote technical support and cost-effective spare parts supply for global clients.