Optimized water cooled EAF cover:
The design of the water cooled furnace cover can achieve the following functions:
(1) The micro-positive pressure and reduction atmosphere in the furnace can meet the smelting process requirements.
(2) Collect the flue gas generated in the smelting process, and send various slag materials and alloys to the furnace.
(3) Reduce heat radiation and heat loss, reduce refractory consumption Furnace cover body for the domestic advanced flow tight row pipe structure, water cooling furnace cover with seamless steel pipe special equal diameter elbow group welding, to ensure that water cooling flow without dead point.
On the structure, the side wall of the furnace cover body is formed into columns and cones, and the top is an inverted cone surface (large at the bottom and small at the top) to ensure rigidity.
Water cooling furnace cover design inlet pressure 0.7MPa, return water pressure 0.4MPa, flow 400 m%h, inlet temperature ≤35 ℃, return water temperature ≤55 ℃.
The electric furnace water-cooled furnace cover is a core thermal insulation and safety component for industrial electric furnaces (such as ferroalloy submerged arc furnaces, calcium carbide furnaces, and electric arc refining furnaces). It covers the top of the furnace body, replacing traditional refractory brick furnace covers with a water-cooled circulation structure. Its main functions are to isolate high-temperature furnace gas, protect the furnace body structure, and create a sealed environment for processes like furnace gas collection—making it a key part of improving electric furnace efficiency, safety, and environmental performance.
It integrates "high-temperature protection, process sealing, and heat control" to address the pain points of traditional refractory covers (short service life, poor sealing, and difficult maintenance):
- High-Temperature Resistance & Protection: Isolates the 1500-2200°C high-temperature environment inside the furnace, preventing direct scouring of the furnace body shell by high-temperature gas and molten splashes, and avoiding deformation or burnout of the steel structure.
- Sealing & Furnace Gas Management: For closed electric furnaces (e.g., closed calcium carbide furnaces), it forms an airtight space with the furnace body to prevent leakage of toxic and flammable furnace gas (such as CO) and ensure efficient collection of furnace gas for energy recycling.
- Heat Loss Reduction: The water-cooled structure reduces heat dissipation from the furnace top (compared to traditional refractory covers, heat loss can be reduced by 30%-50%), improving the furnace’s thermal efficiency and reducing energy consumption.
- Easy Maintenance: Avoids frequent replacement of refractory bricks (traditional covers need to be repaired every 1-3 months), extending the service life to 3-5 years and reducing shutdown maintenance time.
It relies on a closed water circulation system to take away heat and maintain structural stability:
- The furnace cover body is designed with a hollow interlayer (or built-in water-cooled pipes), and cooling water (softened water or demineralized water) is continuously injected into the interlayer/pipes through a water supply pump.
- When the furnace is in operation, high-temperature furnace gas and radiation heat transfer heat to the furnace cover’s inner wall; the cooling water absorbs this heat and flows out of the furnace cover through the return pipe.
- The heated cooling water is sent to a cooling tower or heat exchanger to reduce its temperature (usually from 50-60°C to 30-40°C), then recycled back to the furnace cover—forming a closed, low-energy-consumption circulation system.
The water-cooled furnace cover has a modular design, and its structure and materials are strictly matched to the electric furnace’s working conditions (temperature, pressure, furnace gas corrosion):
The design parameters of the water-cooled furnace cover are determined by the electric furnace’s type, capacity, and process requirements. The core parameters include:
- Cooling Water Parameters:
- Inlet temperature: ≤40°C (too high will reduce heat absorption efficiency);
- Outlet temperature: ≤60°C (prevents scaling in pipes due to high temperature);
- Water pressure: 0.4-0.6 MPa (ensures sufficient water flow to avoid local overheating);
- Water flow rate: Calculated based on furnace capacity (e.g., 40MVA calcium carbide furnace requires a water flow rate of 80-100 m³/h).
- Structural Parameters:
- Thickness of water-cooled panel: 8-12 mm (balances heat resistance and heat transfer efficiency);
- Pipe spacing: 150-250 mm (ensures uniform cooling, no local hot spots);
- Sealing pressure: ≥0.1 MPa (ensures no furnace gas leakage, meets environmental standards).
- Service Performance Parameters:
- Maximum withstand temperature: 1800-2200°C (inner wall);
- Heat dissipation coefficient: ≤150 W/(m²·K) (lower than traditional refractory covers’ 300-400 W/(m²·K));
- Leakage rate: ≤0.1% (furnace gas leakage rate, meets GB 16297 emission standards).
It is widely used in various industrial electric furnaces, and its design is customized according to the furnace’s working conditions:
To ensure the safe and stable operation of the water-cooled furnace cover, regular maintenance and timely fault handling are essential:
- Check Water Circulation: Monitor cooling water inlet/outlet temperature, pressure, and flow rate—if the outlet temperature exceeds 60°C or the pressure drops by ≥0.1 MPa, stop the furnace for inspection immediately.
- Sealing Inspection: Check the furnace cover’s edge gasket for cracks or aging; wipe the sealing surface clean and replace the gasket if there is furnace gas leakage (detected by a gas detector).
- Pipe Inspection: Inspect water inlet/outlet joints for leakage; use an infrared thermometer to scan the cover body—if local temperature exceeds 80°C, there may be pipe blockage or water shortage.
Furnace cover diagram:
