Power plant boilers, steam turbines, and generators are the main engines of thermal power plants, therefore power plant boilers are important equipment for producing electrical energy. Industrial boilers are essential equipment for providing steam required for production and heating in various industrial enterprises. There are many industrial boilers that require a large amount of fuel consumption. The use of high-temperature exhaust gas as a heat source in the production process plays an important role in energy conservation for waste heat boilers. Marine boilers are installed on various ships, and the steam generated is used to drive steam powered machinery. As the main equipment of steam locomotives, locomotive boilers still have certain applications.