Project Background and Core Process Requirements

WONDERY recently completed the delivery of an HRJ3-150-11 large-scale pit-type anaerobic annealing furnace. Designed for non-ferrous metal parts and pipes, the project required a strictly anaerobic environment at 800-1000 ℃ to prevent oxidation. The client prioritized atmosphere integrity and temperature uniformity for large-diameter workpieces (Ø1400mm).

Technical Solutions and Parameterized Evidence

1. Reinforced 310S Vacuum Muffle Structure

To meet the requirements of sealed heat treatment, WONDERY optimized the muffle design:

• Material Specifications: The muffle is welded from 10mm thick 310S (0Cr25Ni20) heat-resistant stainless steel, featuring an elliptical head at the bottom to manage thermal stress.

• Dual Sealing Technology: The flange is precision-machined from 304mm carbon steel, integrating a high-temperature silicone seal at the top and a water-cooling channel at the bottom. Secured by 10 manual compression screws, it ensures zero leakage during high-temperature cycles.

2. Dual-Zone Control and Thermal Consistency (±10 ℃)

Given the large dimensions, a zoned control strategy was employed to eliminate vertical gradients:

• Control Architecture: The furnace is divided into 2 independent heating zones, each with its own group of elements.

• Precision Hardware: Powered by a Japanese Shimaden PID controller and a 10.1-inch industrial touchscreen, maintaining temperature field uniformity within ±10 ℃.

• Ramp-up Efficiency: With a rated power of 150kW (1-100% adjustable), the non-load heating time is ≤1.5 hours, enhancing throughput.

3. Ceramic Screw Wall-Mounted Heating System

• Material Standards: Elements are made of 0Cr25Al5 high-resistance alloy strips, with φ16 lead-out rods ensuring reliable high-current transmission.

• Short-Circuit Prevention: Strips are secured using specialized high-alumina ceramic screws and washers. This creates a gap between the fiber lining and the elements, maximizing heat radiation while eliminating the risk of thermal short circuits to the shell.

4. High-Efficiency All-Fiber Insulation

• Lining Process: The furnace utilizes all-fiber insulation sourced from Shandong Luyang.

• Energy Performance: Through high-density compression, the empty furnace power loss is restricted to 15kW, significantly reducing long-term operational costs.

Delivery Specifications and Key Parameters

• Effective Working Dimensions: Ø 1400 × 1500 mm.

• Design Temperature: 1100 ℃ (Normal use: 800-1000 ℃).

• Automation: Features process curve recording, over-temperature audio-visual alarms, and safety interlocks.

• Atmosphere Support: Includes dedicated ports for nitrogen or other inert gas protection.