Composite tube null for heat transfer of exhaust gas waste heat utilization boiler of

摘要

PURPOSE: To produce a laminated tube for heat transfer for a boiler utilizing waste heat of waste incineration furnace exhaust gas. ;CONSTITUTION: This laminated tube can be formed by constituting the inner layer with an ordinary boiler steel and also constituting the outer layer with an Ni-base alloy which has a composition consisting of 20-25% Cr, 18-25% Mo, 0.5-5% Nb, 0.01-7% Fe, ≤0.05% C, ≤0.1% Si, ≤0.03% P, ≤0.03% S, and the balance Ni with other impurities and further containing, if necessary, 0.1-2% W and/or one or ≥2 kinds among 0.001-0.1% rare earth element, 0.001-0.1% Y, 0.001-0.1% Zr, 0.001-0.01% Hf, and 0.001-0.01% B.;COPYRIGHT: (C)1996,JPO