Products
Tubular Heat Exchangers
CORTEX® Core Tubular Heat Exchangers
Heat Exchanger Operating in Corrosive Environments
APEX Group develops, fabricates and supplies a range of proprietary non-pressurized tubular heat exchangers. The heat transfer elements are made of bare cylindrical or oval tubes, arranged in triangular, square or rectangular pattern.
Our CORTEX Heat Exchangers are upgraded with A-CORREX® Technology to operate with flue gasses below the acid dew point to further decrease the exhaust flue gas temperature.
Key Features
Characteristics:
- Constructed from metallic (glass-enameled or polymer lined) or polymer composite tubes
- Suitable for working with corrosive (condensing) fluids (with A-CORREX® Technology)
- Easy replacement of the heat transfer elements
- Easy to wash due to smooth Glass enameled or polymeric surface
- Simple and cost effective construction
- Good response to thermal cycles and thermal shocks
- Relatively higher pressure drop and lower thermal effectiveness is achieved comparing to CORPEX® or V-FLEX® heat exchanger of the same size.
Fluids Handled:
- Combustion Air
- Flue gas from combustion of: gaseous fuels, liquid fuels, coal, wood, waste, biomass
- Vapor, condensing or non-condensing
- Industrial exhaust streams
Typical Services:
- Combustion Air Preheater
- Gas-Gas Heater
- Flue Gas Cooler/ Condenser
Typical Technical Specifications:
- Design Temperature: Up to 260 °C (possible higher)
- Design Differential Pressure: Up to 0.5 barg
- Duty Range: Unlimited
- Thermal Effectiveness: ~70%
- Pressure Drop Rates: 0-0.1 barg (max. 0.5 barg)
- Leakage Rate: Less than 0.1%


Applicable Technologies:
- AIR CURTAIN® Technology – to control heat transfer surface temperature to avoid “cold corner” corrosion.
- A-CORREX® Technology – to prevent acid dew point or water dew point corrosion.
Corrosion Resistant Materials
1. Glass-Enameled Carbon Steel
- Made from carbon/stainless steel enameled with borosilicate glass
- Resistant to Sulfuric Acid
- High thermal conductivity of carbon steel
- Extremely smooth, effectively repelling fouling and easily cleanable with water or steam
- Operating temperature up to 260°C (up to 450°C possible)
- Good resistance to heat cycles and thermal shocks
- Easily replaceable heat transfer elements (tubes)
- Mechanical strength of the metallic substrate
- Extremely smooth, effectively repelling fouling and easily cleanable with water or steam.

2. Polymer Composite
- Made from a special type of Polymer, featuring a higher thermal conductivity compared to pure polymers
- Resistant to virtually any chemical attack below Acid Dew Point and Water Dew Point
- Operating temperature up to 200 °C (short term peaks 220 °C)
- Good resistance to heat cycles
- Easy replaceable heat transfer elements (tubes)
- Light weight
