PARTS FOR FLUID

摘要

A specified metal member included among the components of a valve, coupling or like fluid handling part for use in piping and fluid control devices is made of an alloy comprising, in % by weight, 0.001 to 0.01% of C, up to 5% of Si, up to 2% of Mn, up to 0.03% of P, up to 100 ppm of S, up to 50 ppm of O, 18 to 25% of Cr, 15 to 25% of Ni, 4.5 to 7.0% of Mo, 0.5 to 3.0% of Cu, 0.1 to 0.3% of N, and the balance substantially Fe and other inevitable impurities, the alloy having a CRI (crevice corrosion resistance index) value in the range of 40 ≤ CRI ≤ 55, as determined from the expression CRI = ÄCrÜ + 4 x ÄMoÜ + 30 x ÄNÜ wherein the amount of alloy components present in combination in the alloy to ensure crevice corrosion resistance are expressed in %by weight. <IMAGE>