... cost 3.ISO9001:2000 Certification Description:1,air flow:1000----1000000Nm3/h 2,filter speed:0.2--1.2N/min 3 ... boiler operation stability effectively,prevents boiler going positive pressure and filter bag damage caused by uneven flue gas.3, PLC control ... system etc,widely used in metallurgy, chemical,non-ferrous metal smelting,building material,cement and other fields. certificate long pulse bag filter