Root blowers, compressors, and accessories, rotary feeders, dust removal equipment, diverter valves, centrifugal fans, castings, pneumatic conveying equipment, evaporator equipment, environmental protection equipment production and sales; design, research and development, production, and sales of high and low voltage complete electrical appliances and accessories, boiler auxiliary equipment, power auxiliary equipment, electrical control cabinets; design and construction of pneumatic conveying projects; sales of hardware, building materials; mechanical parts processing; import and export of goods, technology import and export, and other projects not prohibited by laws, regulations, and decisions of the State Council and do not require business licenses.