Cold Jet E-CO2 150, Operator'S Manual

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Setting the Abrasive Flow
The Abrasive Metering Valve (figure 20) can be set to deliver between 1.2-10 lb/min (.5-4.5 kg/min) of
abrasive. The knob can only be turned when you are not blasting or in the ice only mode. It usually
takes about 6 complete turns (counter-clockwise) of the knob from the completely closed position to
start the abrasive flowing. Once abrasive is flowing it only takes small adjustments of 1/8 to 1/4 turn
to make a significant change in flow. There are indicator markings on the stem that indicate how
many turns the knob is out (figure 20). It is usually best to have the abrasive set to a minimum flow
but this can be set to operator’s choice.
If there is ice but no abrasive flowing and you are sure the Pot has abrasive in it - check to see that
the toggle switch is in the ABRASIVE/DRY ICE position. If there is still no abrasive flowing make sure
the Metering Valve is open by turning the valve counter-clockwise until abrasive flows (this can be
readjusted later to obtain desired abrasive flow).
Full Turn Indicators
Quarter Turn Indicators
Figure 20: Abrasive Metering Valve
Dry Ice Feed Metering Valve W/Medium Grade Abrasive
lb/min (kg/min) Knob Turns lb/min (kg/min)
1.5 (.68) 6 1.6 (.7)
2.0 (.9) 6.5 3.4 (1.5)
2.5 (1.1) 7 4.6 (2)
3.0 (1.4) 7.5 5.6 (2.5)
3.5 (1.6) 8 6.4 (2.9)
4.0 (1.8) 8.5 7.2 (3.2)
4.5 (2) 9 8.4 (3.8)
5.0 (2.3) 9.5 9.2 (4.2)
5.5 (2.5) 10 10 (4.5)
6.0 (2.7) 10.5 10.8 (4.9)
The above values are recommendations and approximate settings. In general,
the larger the abrasive size the further the metering valve will need to be open
which will require more dry ice to keep the dust minimal.