Wallace & Tiernan SERIES V-2000, Руководство пользователя

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WT.025.055.004.UA.IM.0814
MANUAL CHLORINATOR - 3000LB/24HR
EVOQUA W3T109620
WARNING: TO AVOID POSSIBLE SEVERE PERSONAL INJURY OR EQUIP-
MENT DAMAGE WHEN USING HYDROCHLORIC ACID, OBSERVE ALL SAFETY
PRECAUTIONS RECOMMENDED BY THE ACID MANUFACTURER/SUPPLIER.
If the upstream strainer becomes corroded or perforated and passes a small
pebble or other tramp material, such particles can partially plug the throat and
prevent adequate flow. Water containing suspended silt or sand particles can
erode the opening in the throat. As this opening is enlarged, the water velocity
decreases, thereby decreasing the vacuum developed.
The injector should develop a dynamic vacuum of at least six inches of mercury
at maximum capacity flow rate. At lower gas feed rates it tends to be higher
for the same hydraulic conditions. With the gas completely shut off, the static
vacuum should be about 25 to 28 inches of mercury.
If the gas feeder fails to operate, inadequate vacuum is the most common
reason and the injector is the first place to check. Proceed as described in
Paragraph 4.12.7, Troubleshooting.
4.11.6 Cleaning 3/4" Fixed Throat Injector (Standard) (See Dwg. 25.200.002.010)
The check valve prevents water from the injector from being drawn back by the
vacuum prevailing at shutdown into the control unit and toward the vacuum
regulator during the OFF period.
In continuous or nearly continuous operation, this valve is actuated very little,
and the recommended annual check is principally to ensure cleanliness. In
automatic start-stop operation, the check valve can accumulate thousands of
opening and closing cycles in six months or less and wear becomes a consider-
ation in addition to clean surfaces. For either interval the procedure is as follows:
• Cleaning Injector Unit Diaphragm Backcheck.
a. Shut off injector operating water.
b. Take steps to prevent water flowing back toward the injector from the
point of application.
c. Unscrew gas line tubing nut and remove tubing.
d. Unscrew injector body union nut (10).
e. Unscrew valve stem (8) in the center of the top of the upper body
(32). Wipe the surface of the spherical tip of valve stem with a clean
cloth or paper towel to remove any loose material. Soak briefly in
10% muriatic (hydrochloric) acid if there are any deposits that do not
wipe away with plain water. If the spherical surface is indented, worn,
eroded, or scratched, replace valve stem.
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