-On the evaporating tube surface there are high density of pore which are interconnected by tunnels below the surface. The structured surfaces exist more nucleation sites and allow the liquid to flow into tunnels quickly, thus it enhance the boiling heat transfer¡C
-Its heat transfer coefficient is about 4 times higher than a plain.
-The evaporator with the structured surfaces tube can reduce the volume and metal of evaporator. It is evident that the production cost will cut down.
-It will reduce energy consume when condenser is operating.

-The surface structure reduces liquid film thickness and the spiral grooves inside tube enhances internally heat exchange, thus they raise the condensing heat transfer coefficient under two actions.
-Its heat transfer coefficient is 3¡X4 times higher than a plain.
-Because of high heat transfer and large heat exchange area, the number is reduced of heat exchange tube used in condenser, then it will reduce the volume and metal of condenser. It is evident that the production cost will cut down.
-It will reduce energy consume when condenser is operating.

-The corrugated tubes are applied to condition and other heat exchanger
-There are flutes inside and outside a tube surface. Its affect disturb the flow field near the wall and enhance heat transfer. In same time the flute increase surface area.

-There are the grooves inside tubes. It increases the heat transfer surface area and effects the flow field near a wall. In this case it enhances the heat transfer.
-The heat transfer coefficient increases about one time
-The pressure drop in a internally finned tube is only 20% higher than that of a plain.
-It draws heat of water outside tube and reduces the temperature of water when refrigerant is boiling in tube. Chiller with the internally finned tubes can be used in condition.
-In general the internally finned tube is manufactured into straight, given length and hardness according to a design.