Variants for every demand
Air preheater are heat exchangers for heating and evaporation, for cooling and condensing and for heat recovery. Many decades of experience in designing and manufacturing have made us a leading supplier of heat exchangers for cooling and heating of gaseous and liquid media. The wide range of available plain and finned tube systems is certainly an important aspect of our market success.
Finned-tube heat exchangers can be made from numerous materials: steel, stainless steel, copper/aluminum, aluminum and other special materials. Plain-tube heat exchangers are used mostly where a fluid present around the tubes is so polluted that finned tubes can no longer be used. Plain tubes can be configured in different ways either next to one another or serially. Steel and stainless steel versions as well as a hairpin design are also possible.
- Aerodynamically favourable core tube with roughly three to ten times less hydraulic friction as compared with a round tube
- Good corrosion protection due to hot-dip galvanizing in a dipped bath and at the same time an optimum metal joint between core tube and fin
- High thermal transmittance resulting in small heat exchanger surface
- Low noise Level
- Low pressure loss and minimum soiling
- Compact design leading to good use of a given volume
- Maximum service life
With water, heat transmission coefficients in the order of 5,000 W/m² K can be achieved in the tubes. In contrast, heat transmission is much lower for air. A coefficient of 100 W/m² K may be expected when plain tubes are used. With a view to compensating for the significantly lower heat transmission coefficient for air, thermal engineers increase the outer surface of the tubes by providing them with fins.
Finned tube heat exchangers are available in the following materials:
- Stainless steel
- Copper / Aluminium
- Special materials
Plain tube heat exchangers are mainly used for applications where a fluid flowing outside the tubes is subject to fouling to a point where finned tubes cannot be used. The plain tubes can be arranged at different pitches and alongside or after one another.
Plain tube heat exchangers are available in the following designs: