The purge carriage carrying the glide surface with reverse air nozzles and is driven between filter bag columns via a maintenance free chain gear motor drive. The location of the bag columns and positioning of the purge carriage is controlled by an indexing wheel and proximity sensor which controls the operation of the gear motor via a simple PLC control. The operation of the reverse air cleaning fan and cleaning damper is also interlocked with the operation of the purge carriage via the PLC control.

The reverse air method of cleaning helps to keep a more consistent dust cake on the surface of the filter bags which is important in providing a secondary filtration action critical when handling fine dust particulate and fume. This less server cleaning action helps to reduce the wear on the filter bag fabric ensuring a longer bag life and helping to eliminate fine particulate and fume to bleed through the filter bag fabric.

The advantage with this style of cleaning method and better control over the dust cake is extremely low emission limits can be achieved as indicated below right