Whenever the pump is dismantled from the pipework, you will be well advised to replace the caps on the
connectors to avoid residual liquid being spilled. Before attaching the delivery hose to the plant, prime the
metering pump by going through the sequence shown in Fig. 8. Before finalizing the installation of the dis-
charge hose, make sure that the pump strokes will not cause it to move and bump into rigid bodies. In case
of priming difficulties, use a normal syringe to suck liquid from the discharge nipple while the pump is in
operation, continuing until you actually see the liquid rise in the syringe. Use a short length of suction hose
to connect the syringe to the discharge nipple. In case of a pump equipped with an air bleed valve, unscrew
the air relief valve B up to all the air in the pump head will be out.
f. - Try to keep both the suction and discharge hose as straight as possible, avoiding all unnecessary bends.
g. - Select the most appropriate injection point on a pipe of the plant to be treated and there fit a 3/8" female steel
gas thread connector (similar to BSPm). This connector is not supplied with the pump. Screw the injection
valve to the gas connector, inserting a gasket as shown in Fig. 9. Then connect the discharge hose to the
conical connector on the injection valve and fix it with the supplied tube nut G. The injection valve also acts
as no return valve by means of a cylinder sleeve (elastomer, standard supplied in Viton®).
N.B. The sleeve D must not be removed.
3.1 - INJECTION VALVE INSTALLATION
DIAGRAM Fig. 9
A - Pipework
C - Injection valve
M - Conical connector for attaching the
discharge hose
N - 3/8" female steel gas thread connector
G - Hose tube nut
T - Polyethylene hose
D - Cylinder sleeve (no return valve)
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Fig. 8
Fig. 9