In a refrigeration cycle, (for a higher efficiency) the liquid refrigerant condensed in the condenser and flowing in the capillary tube towards the evaporator should be cooled down, while the vapor refrigerant sucked by the compressor from the evaporator through the suction tube should be heated up (from saturated to superheated condition). So the two tubes are brought together to achive both of these objectives and this twin tube system is called “heat exchanger” or “suction tube assembly” of the refrigeration cycle.

To help the heat exchange, the two tubes can be soldered together as in the case of tube-on-tube copper heat exchangers; or the capillary tube can be passed through the suction tube as in case of Al-Cu mono-tube heat exchangers. 
In KONVEYOR, both of the two types and also some special ones for special freezers (like combi, frost-free, or home air conditioner) are manufactured in large quantities.

Copper, capillary and (partially) aluminum tubes supplied from major European manufacturers, are cut to lengths and brought together by using special machines.

Aluminum-copper connections of the mono-tube suction tubes are performed mainly by reliable and competitive ultrasonic soldering method with more than 15 years of KONVEYOR experience in this application.