Irregular Abrasive Flow - Nederman Vacuum Blaster Manual De Usuario

Problem
Not enough abrasive flows out of
the nozzle or nothing at all.
7.1

Irregular Abrasive Flow

If clean abrasive is refilled and no blockage found it is still possible that the abrasive
flow is irregular or doesn't come at all. This is pointing at an over-pressure of the
transportation air that is caused by leakage at the pot of Vacuum Blaster. First check
if the decompression valve is completely closed. This is best done by a second person.
Remove the silencer and check if no air come out during blasting. Wear protective
items! If air comes out check the valve and the membrane.
If this is OK check the following connections very carefully with soap-suds, when
Vacuum Blaster is working.
1. Filling cone ring - filling cone.
2. Pot - abrasive metering valve.
3. Pot - decompression valve.
4. The piping to the guiding pipe.
5. The gasket of the inspection hatch.
6. Diaphragm of the decompression valve.
If after following these points problems still occur, please contact your supplier or the
manufacturer.
Cause
Metering valve is closed.
No signal to the abrasive metering
valve.
The abrasive metering valve doesn't
open.
There is a blockage.
There is a blockage too big to be
pumped through.
There is a big blockage at the bottom
of the pot.
Vacuum Blaster
Solution
Open metering valve, default 3
turns.
Check the installed remote control
system.
If the compressor's capacity is too
small for the chosen blastpressure/
nozzle the system pressure will drop.
Check if during blasting the system
pressure gauge remains above 5
bar. This is the minimum pressure
required to open the metering valve
against the spring's tension.
Check the parts of the valve on
damages / wear
Close and open the choke valve 3-4
times quickly during blasting. The
pot will be in a 'over-pressure' and
small blockages will be pumped
through the orifice of the media
metering valve
Open the metering valve completely
by turning the knob anti clockwise.
When the blockage is gone put the
valve back to its former setting.
Remove the metering valve and
clean the outlet at the bottom.
EN
27