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  NQB1 and NQB2 inherited the advantages of QB1 and QB2 as wellas added other advanced  use function of electric actuators.They are always used in ball vavle ,butterfly valve ,plug valve and other 90?_turn valves.NQB1 and NQB2 seris valve electric actuators are wildly used in petrochemicai,matallurgy,energy sources ,municipal ,light industry ,food and other fpipeline aontrol system. QBR 3 to 5 ,torque rang are from 900 to 12000NM,were developed by our company.The electric actuators, combination of these seris and butterfly valve,were used to control the open and close of valve