PROBLEM TO BE SOLVED: To provide a pipe for water-cooling system and non-water-cooling system heat exchangers operating under an environment where there are high mechanical abrasion in a melting furnace, high corrosive performance and high temperature and high conductive performance, and/or heat stress is received.SOLUTION: A pipe has an inner pipe, and an outer pipe that covers and contacts the inner pipe and is resistant to corrosive gas with a temperature of Celsius 2204.4°-Celsius 2760° (Fahrenheit 4000°-Fahrenheit 5000°) while contacting the corrosive gas. The inner pipe and the outer pipe coaxially have the same length. The inner pipe is manufactured by a first selected material, and the outer pipe is manufactured by a second selected material that is a material other than carbon steel. The inner pipe and the outer pipe are subjected to extrusion molding together.