What is the impact of over-temperature on the service life of the tubes?

　　Various steam and water tubes and boiler heating surface tubes are designed for service life according to a certain working temperature and stress. If the working temperature exceeds the design temperature during operation, although it is not overheated, the stability of the metal structure will become worse and the creep speed will increase. Finally, its service life is shortened.

　　According to experimental research, the time for a material to reach failure is inversely proportional to the creep rate, which shortens exponentially with the increase of temperature.