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Operation and maintenance manual for
Hydrotech Discfilter HSF31-series
7. Place the spray bar to its initial position.
8. Put back the removed lids.
9. Set the safety switch to ON and the selector switch to AUTO
WARNING!
It is important that the bayonet nozzle nuts (see figure 7.1.1d) are
reassembled correctly after cleaning of the nozzles. If a nut loosens, the
nozzle will fall out and the resulting water jet can destroy the filter cloth.
7.1.2.Checking.the.spray.nozzles.for.wear
The nozzles will eventually be worn out and a replacement will be necessary.
The life length depends on the quality of the rinse water. If the rinse water
contains coarse sand or similar particles, the nozzles will be worn out faster
than a nozzle that operates in “clean” rinse water. When a nozzle becomes
worn out, the nozzle tip opening becomes enlarged (see
Figure 7.1.2b
). This
leads to a less efficient back wash (changed dispersion) and higher rinse
water consumption. Therefore it is important to regularly check the functionality
of the nozzles (at least once every year) and change the nozzles if needed.
A comparison between a worn
out nozzle and a brand new
nozzle is shown in
Figure 7.1.2
.
In the worn out nozzle, a change
in the nozzle opening can be
seen.
!
Figure 7.1.2 a
New nozzle
Figure 7.1.2 b
Worn out nozzle