– Lower weight, higher performance

Save cost and reduce weight

Weight reduction will be 15 per cent when heatexchangers adopt two-piece folded tube. Total costsaving will be 5–20 per cent for a two-piece folded tube heat exchanger.

Excellent thermal performance

The tube wall thickness can be reduced up to 20 per cent when compared to that of a traditional extruded tube, providing a larger free flow area for the refrigerant, thus reducing refrigerant side pressure drop. Small hydraulic diameter, along with the micro-channel flow characteristics, provide for excellent heat transfer on the refrigerant side.

Superior corrosion resistance

Because Gränges tube stock materials can have built-in corrosion protection mechanisms, such as brown-band and protective multi-layers, there is no need for additional Zn coating, resulting not only in a longer time to failure, but also improved heat exchanger integrity throughout the whole lifetime. A Folded Tube heat exchanger with Gränges MULTICLAD® system can be leak-free after 100 days of SWAAT testing (ASTM G85-A3).

Microchannel folded tube is produced by precise roll forming of an aluminum tube stock material. One kind is two-piece folded tube, which outside tube and inner fin are formed separately and then assembled to be a whole tube. Another is one-piece folded tube formed by one single aluminumstrip. Folded tube can be used as refrigerant tube in brazed aluminum heat exchangers such as condensers and evaporators for automotive, as well as air conditioning and refrigeration applications. Combining Folded Tube technology with Gränges’ portfolio of tube stock materials enable high reliability, light weight, cost reduction and improved performance.




Outside dimension W x H (mm) 12 x 1.4 16 x 1.8
Port number 20 12
Wall thickness (mm) 0.20 0.24
Inner fin thickness (mm) 0.08 0.24
Available lenght (mm) 300-1,000 300-1,000
Burst pressure (MPa) 18-20 18-23
Weight (g/m) 20.03 36.43
Delivery condition Internal fluxed Internal fluxed


Get in touch with us

Yabiao Ling

General Manager, Fold Tube, Gränges Asia