Recently our company has supplied a batch of tubes which have an Inconel 625 alloy cladding layer on its external surface. The base meterials of Inconel 625 clad medium carbon steel seamless tubes are manufactured as per ASTM A210/ASME SA-210 grade A1. They are furnished for the construction of a preliminary superheater of a refuse incineration boiler. Due to the severe working conditions, the external surface of the tube shall be cladded with a 3mm-thick CRA layer-Inconel alloy 625(UNS N06625), which exhibits excellent corrosion resistance at elevated temperatures. The alloy 625 is weld overlaid to form a firm metallurgical bonding with the backing steel. These tubes are supplied to a contractor in Belarus: size O.D 50.8 mm x 4.6 mm and O.D 76.1 mm x 5.8 mm.