HEAT TRANSFER PIPE

摘要

PROBLEM TO BE SOLVED: To provide a heat transfer pipe in which either refrigerant or absorbing liquid can diffuse more smoothly even if its diameter is small, capacity is enhanced and reduction in size can be attained. SOLUTION: There is provided a heat transfer pipe used in either an evaporator or an absorbing device. An outer circumferentical surface of the heat transfer pipe 1 is formed with helical fins 1a having a large twisting angleθin respect to an axis of the pipe and a height(h) of 0.2 to 0.95 mm. The fins 1a are formed with some protrusions 10 along a longitudinal direction of the fins 1a and notched recess portions 11 in repeated manner in normal or reverse state, and at least one step 12 is formed from the apex parts of the protrusions 10 to the bottom parts of the recessed portions 11.