1. Basic Structure

The stainless steel welded plate-type air-to-air heat exchanger consists of multiple corrugated stainless steel plates that are welded together to form alternating channels for hot and cold airflows. The plates act as barriers to separate the two air streams while conducting heat between them.

• Material: Commonly made of 304 or 316 stainless steel, offering strong corrosion resistance and mechanical durability.

• Welding Method: Typically uses laser or spot welding to ensure airtight channels and withstand high temperature and pressure.

• Flow Configuration: Can be arranged in crossflow, counterflow, or parallel flow to maximize heat transfer efficiency.

2. Working Principle (Explained with the Diagram in Mind)

1. Hot and Cold Air Enter Separate Channels

   • The red airflow (e.g., high-temperature exhaust gas) enters one side and passes through the hot air channels.

   • The blue airflow (e.g., fresh cold air) enters from the opposite side and flows through the cold air channels.

2. Heat is Transferred Through the Stainless Steel Plates

   • The two airstreams flow in adjacent, sealed channels and do not mix.

   • Heat from the hot air is conducted through the thin metal plates to the cold air.

   • The fresh air is heated, while the exhaust air is cooled and then discharged.

3. Efficient Heat Exchange with Crossflow or Counterflow

   • Using a crossflow or counterflow layout increases the temperature difference between the streams and improves heat recovery efficiency.

4. Discharge of Air After Heat Exchange

   • The heated fresh air proceeds to the next process (e.g., drying or preheating).

   • The cooled exhaust air is either discharged or treated in an emission control system.

3. Technical Advantages

• Corrosion and high-temperature resistance due to full stainless steel construction

• No moving parts, ensuring stable, maintenance-free operation

• High energy efficiency through thin metal plates and turbulent flow

• Modular design, allowing for flexible installation and capacity scaling

• Complete flow separation, preventing any cross-contamination—suitable for clean air systems

4. Typical Applications

• Waste heat recovery from industrial exhaust (e.g., painting lines, dryers, ovens, printing machines)

• Preheating fresh air in HVAC systems

• Utilizing exhaust heat in drying processes

• Cooling hot air and recovering residual heat

• Pre-treatment cooling before VOC or dust removal systems