Reverse Air Filters

Key to the RAF’s high reliability and performance is its simple,effective cleaning system. Bags are cleaned by high volume, low pressure reverse air every two minutes.


The Reverse Air Filter II (RAF II) utilises two techniques to remove dust: cyclonic separation and media filtration. Each bag is cleaned once every 120 seconds by utilising the efficient reversed flow of processed air. This complete and systematic cleaning dramatically reduces the pressure drop across the media as well as the load demands on the complete fan system. Systems that employ random air pump cleaning may require the same horsepower, but do not clean each bag every 120 seconds. Because of this, some bags can go for an extended time without cleaning, causing higher pressure drops across the media, which increases demands on the total fan system and ultimately leads to higher energy costs.

Features and Benefites

  • Save energy with low pressure drop, low fan HP, recycled clean air
  • Superior operating performance with integral cleaning fan
  • Easy maintenance with top bag removal and sectionalised tube sheets
  • Reduce maintenance costs - no valves, dampers, compressors, or PD pump to maintain


The RAF-IS Reverse Air Filter is specifically designed for highly combustible dust and high temperature applications. The RAF-IS dust collector is ideally suited for all coal (including PRB) filtration applications. It combines high performance, low energy use, and reliable and effective reverse-air cleaning in a ledge-less filter housing totally free of internal electrical components. These features make it ideal for flammable dust applications:

  • All electrical components are outside the filter housing.
  • Simple, effective cleaning mechanism continuously sweeps filter bag plate.
  • Cleaning system recycles the filtered air, so no outside oxygen is introduced.
  • No flat surfaces where dust can accumulate.
  • Involute inlet is clad with replaceable anti-spark wear resistant plates.
  • 60° (70° optional) hopper with flush mounted inspection door prevents dust accumulation.


Downloadable Documents

RAF II Reverse Air Filter

RAF II specs

RAF-IS Reverse Air Filter for Highly Combustible Dust and High Temperature Applications

RAF-IS overview