Product Function; Main Filtration; Control Filter - Nederman FlexFilter EX Manual De Instrucciones

This accessory works with the control system to increase efficiency when
changing Bulk-bags. It also ensures that no unnecessary alarms are triggered if
bag change occurs simultaneously to the control system trying to operate the
TVFD.
Filter alarm
Pressure switch signalling if the pressure over the main filter exceeds a set
value.
Fire alarm
Detects a fire in the filter and signals the control system.
Reverse Flow (RF) kit
The Reverse Flow kit has an arrangement of valves and uses the capacity of
the vacuum unit to clean one filter module while the other remains in normal
operation. RF is suitable for "hard to clean dust", or if the vacuum level is
insufficient to generate a powerful blast of air during normal filter cleaning.
7

Product function

7.1

Main Filtration

The filtration process is described in the following step 1-5 (see picture no. 6).
1. The inlet module separate coarse particles.
2. The coarse particles pass the cone.
3. The coarse particles fall down into the feed out device (TVFD).
4. Fine dust particles follow the up-going air flow through the filter unit.
The particles are separated on the outside surface of the filter bags. A
long spiral spring in each filter bag keeps it from flattening as air passes
through the bag from outside to inside.
5. The filtered air leaves the collector.
6. The filtered air continuous through the control filter.
The pressure drop increases as more fine dust settles on the filter bags. During
filter cleaning, part of the dust is dislodged and falls down into the collecting
module. It is not desirable to dislodge all the dust. A certain quantity of fine
particles on the filter bags improves particle separation compared to using
clean bags.
Different kinds of dust have widely different properties. Some kinds are easily
cleaned off the filter bags while others require more powerful cleaning.
FlexFilter EX with standard filter cleaning uses its own vacuum to generate a
short blast of air backwards through the filter bags. A compressed air cylinder
in the top module opens a disc valve so that atmospheric air can rush into the
collector to neutralize the vacuum stored inside the collector. The higher the
vacuum and the larger the connected piping system, the more air will flush
backwards through the filter bags and the cleaning will be more effective.
7.2

Control filter

The FlexFilter EX is equipped with a control filter. The control filter filters the
air after the main filter to ensure that no material continues to the suction
source in case of a main filter breakage. The control filter functions as a safety
device and does not increase the filtration efficiency.
FlexFilter EX EN
37