LEVEL WOUND COIL, METHOD FOR MANUFACTURING THE LEVEL WOUND COIL, CROSS FIN TUBE TYPE HEAT EXCHANGER, AND METHOD FOR MANUFACTURING THE CROSS FIN TUBE TYPE HEAT EXCHANGER

摘要

PROBLEM TO BE SOLVED: To provide a seamless tube made of copper alloy having a high strength and capable of normally performing hairpin bending.;SOLUTION: A level wound coil including a seamless tube multiwound in alignment in a cylindrical shape is characterized in that a material of the seamless tube wound into the level wound coil is a copper alloy containing 0.58-0.72 mass% Sn, 0.005-0.035 mass% Zr, 0.03-0.08 mass% Ni, and 0.004-0.040 mass% P, with the balance being Cu and inevitable impurities, a ratio (t/D) of a thickness (mm) to an outer diameter (mm) of the seamless tube wound into the level wound coil is 0.040 or lower, a tensile strength (σ_B) of the seamless tube wound into the level wound coil is 270 MPa or higher, a 0.2% proof stress (σ_0.2) is 150 MPa or lower, and an elongation (δ) is 40% or higher.;COPYRIGHT: (C)2014,JPO&INPIT