... , Volume:500~21000m3/h, Speed:870~3500r/min, Shipbuilding ventilation fan for shipyard use Draft fan:Weight:25~352kg,Volume:500~21000m3/h ... ,Speed:870~3500r/min,Pressure:490~1800Pa,Voltage:380V/440V,50HZ ... ,Jiushui Road,Licang District,Qingdao,Shandong province,China Shipbuilding ventilation fan--Centrifugal fan