After years of research, they invented high-speed switching device, honeycomb regenerator and other air preheating equipment and devices.

The energy-saving technology makes it possible to use anthracite, instead of liquid fuel, in industrial furnaces, make full use of heat by raising combustion rate of fuel and reduce consumption of fuel.

The technology has been applied to some industrial establishments like the Kim Chaek Iron and Steel Complex, Hwanghae Iron and Steel Complex and Hoeryong Earthenware Factory.