Walchem EH Series, Инструкция по эксплуатации

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2.4 Discharge Tubing
Cut a length of tubing long enough to go from the pump to the application
(injection) point. Additional tubing can be ordered from your distributor. Avoid
sharp turns or bends and hot surfaces. Routing tubing through rigid pipe such as
PVC pipe is recommended for long runs and/or as protective shielding against
corrosive chemicals. If applicable, install the injection valve in 1/2” NPT thread
at the injection point (see section 2.5) and connect the discharge tubing to the
injection valve.
Attach tubing as described in section 2.3 and as shown in Figures 5 and 6. Note:
Some models have an air vent valve with two outlet connections. The
connection marked ‘OUT’ is the discharge side to the application point. (Fig 6).
Attach a second length of tubing to the air vent side marked (‘AIR’) and route
back to the chemical solution tank or drum. On the larger pumps (30 & 35
sizes), the air vent valve connections are not marked, however, the discharge side
is the vertical (UP) connection and the air vent connection is on the side of the
valve.
Figure 6 Air Vent Valve Tubing
2.5 Installing Injection/BackPressure Valve
A fitting or tee with 1/2” NPTF threads and with sufficient depth will accept the
injection valve assembly. If required, trim off an amount of the extension tip
until it fits your fitting or tee. (Fig. 7.)
The position of the injection/back pressure valve can be at any orientation as
long as the spring is retained in the valve. DO NOT REMOVE THE SPRING.
Be sure to check and replace the spring as needed. Attach the tubing following
the same instructions in section 2.3, connecting the supply tubing.
CAUTION:
Some chemicals may have reactions as they are injected into the
main flow. For example, sulfuric acid may react with water causing excess heat.
"AIR"
"OUT"
Drains back to tank
Discharges to injection point