Level-wound coil, method for manufacturing level-wound coil, cross-fin tube type heat exchanger, and method for manufacturing cross-fin tube type heat exchanger

摘要

The seamless pipe is a level wound coil wound in a multilayered arrangement in a cylindrical shape, and the material of the seamless pipe wound around the level wound coil is 0.58 to 0.72 mass% of Sn, 0. A copper alloy containing 005 to 0.035% by mass of Zr, 0.01 to 0.10% by mass of Fe and 0.004 to 0.040% by mass of P, the balance being Cu and inevitable impurities, The ratio (t / D) of the wall thickness (mm) to the outer diameter (mm) of the seamless pipe wound around the level-wound coil is 0.040 or less, and the seamless pipe wound around the level-wound coil A level-wound coil characterized by having a tensile strength (σB) of a pipe of 280 MPa or more, a 0.2% proof stress (σ0.2) of 180 MPa or less, and an elongation (δ) of 38% or more. According to the present invention, it is possible to provide a seamless pipe made of a copper alloy that has high strength and can perform hairpin bending normally.