Boiler of a coal thermal power plant procedures heat energy, and ash byproduct (which includes fly ash, and bottom ash). Fly ash is collected by fly ash hoppers which are located along flue gas flow of the plant. Then fly ash is conveyed to fly ash silo by conveying pipelines. To make sure the conveying pipelines operate stable, there are a lot of parameters need to determine accurately. National Research Institute of Mechanical Engineering (Narime) has researched, calculated, designed,and supplied a conveying pipeline sytem (which includes 04 stream for 02 boiler) for Thai Binh 1 coal thermal power plant. The system has average conveying capacity of each stream up to 26 t/h. Currently, the system has worked fine, which is greatly appreciated from the investor.