High-temperature piping product and method for producing same

A high-temperature piping product for flowing a high-temperature fluid, configured from a plurality of primary pipe members and a welding material,

• wherein the primary pipe members are each made from an Ni-based forged alloy which contains Ni, Al, and at least one of Mo and W, the total content of the Mo and the W being 3 mass % or more and 8 mass % or less, and the Ni-based forged alloy having a γ′ phase precipitated therein in 30 volume % or more in which the precipitated γ′ phase has a γ′-phase dissolution temperature of from 920 to 970° C. and a precipitation characteristic of 30 volume % or more in a temperature range of from 700 to 800° C.,
• wherein the welding material is made from an Ni-based cast alloy having a cast structure formed by welding, the Ni-based cast alloy containing Ni, Al, and at least one of Mo and W, the total content of the Mo and the W being 9 mass % or more and 15 mass % or less, and the Ni-based cast alloy having another γ′ phase precipitated therein in 20 volume % or more in which the another precipitated γ′ phase has a γ′-phase dissolution temperature of from 850 to 900° C. and a precipitation characteristic of 20 volume % or more in a temperature range of from 700 and 800° C., and
• wherein the welding material is buttered to the primary pipe members in portions welded to each other.