3
Flow Range
MagnaValve Model Output = 4.54 Vdc Output = 5.00 Vdc
500-24 1200 Lbs/min 500 Kg/min
1. PRODUCT DESCRIPTION
The 5xx-24 Series of MagnaValves are designed to regulate the flow of steel shot or grit in
abrasive blast cleaning and shot peening machines. The valves have a magnetic control sec-
tion (upper portion) and a shot flow rate sensing section (lower portion). Valves are sized by
flow rate capacity, either in pounds/minute or in Kg/minute, and are used in air-blast applica-
tions such as direct pressure, suction blast or gravity-fed nozzle blast machines.
Specify calibration in pounds/minute or Kg/minute and type and size of shot with order.
2. THEORY OF OPERATION
MagnaValves have no moving parts, they rely upon very strong permanent magnets and can-
cellation electromagnets to regulate the flow rate of shot. A signal from a shot flow controller,
model FC-24, will provide the appropriate control signal for flow rate. Power is supplied by an
external (supplied by customer) 24Vdc source. The internal circuitry accepts a 0-10Vdc control
signal and converts this to a proportional duty-cycle control of the output signal for shot flow. As
the shot falls through the lower sensing portion of the valve, a 0-10Vdc signal is generated and
sent back to the FC-24 controller as a flow feedback signal. This feedback signal is compared
to the requested shot flow rate and the output signal is adjusted and sent back to the Magna-
Valve to complete the closed-loop cycle of control.
3. LOCATION OF ADJUSTMENTS
All of the adjustments are accessible from the front of the MagnaValve. See figure 1 for details.
The factory settings should not be changed. The rated flow range is shown on the identification
label. The output signal is 10 Vdc. for Kg/minute calibrated valves and 4.54 Vdc for pounds/
minute calibrated valves.
4. PRELIMINARY ADJUSTMENTS
There are no preliminary adjustments required or recommended. The valve has been tested
and calibrated at the factory prior to shipment. The full-scale range of the valve and the media
type and size are listed on the product label.
5. INSTALLATION
The MagnaValve must be mounted in a vertical position with an adequate supply of media
above it. Pipe unions are recommended to allow correct alignment of the valve. The valve can
be used for all three types of air blast machines, (direct pressure, suction nozzle and gravity as-
sisted suction nozzle).
a. For direct pressure applications a suitable mechanical grit valve or pinch-tube type of shut-
off is necessary to prevent the air pressure from forcing media through the magnetic field.
The mechanical valve can be located either above or below the MagnaValve.
b. For suction blast applications (valve located on floor) an aspiration air inlet must be pro-
vided so the media can be conveyed to the nozzle. A minimum opening of 12mm is recom-
mended. Do not restrict this air inlet since it will increase the suction and may pull media
through the valve.
Note: All MagnaValves are factory calibrated to Kg/min=10 Vdc. To
change to pounds/min see instruction manual for the FC-24 Controller.
