White Knight AT100, Руководство пользователя

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pump operation, it is always best to operate a pump at lower than red line
supply pressures. Life expectancy goes up as supply pressure goes down.
The life of many air driven pumps goes up significantly if the pump is
operated at between 60%-70% of red line pressures, particularly in open loop
systems where there is very little head pressure to slow pump cycling.

PASSING SOLIDS: In any instance where pumps are installed in an
application where solids could be introduced into the liquid, a pre pump filter
such as the White Knight
Catcher

should be installed in the inlet line going
to the pump. These pre pump filters are designed to catch solids before they
get to the pump where they could damage bellows, diaphragms, or other
parts of the pump. Of particular concern are shards from broken wafers in
semiconductor manufacturing. Care should be taken in selecting the pre
pump filter. Some pre pump filters have a very fine screen that screens out
anything that could damage a pump, but screens this fine come with other
problems. Some chemistries including but not limited to sulfuric acid and
phosphoric acid can begin to produce crystals similar in size and shape to
table salt crystals. Such crystals can plug up the screen and cause undue
stress to the pump, particularly to bellows or diaphragms. White Knight does
not cover such damage under warranty. While there is no perfect size of
screen that keeps out the bad without plugging up, the best scenario is to use
White Knight
Catcher

pre pump filters. With the Catcher

the screen is
large enough to keep from becoming plugged in normal industry conditions.
And, when a
Catcher

is used in conjunction with a White Knight pump, if a
solid passes through the Catcher

and damages the pumps (very unlikely)
White Knight will repair the pump under warranty.

OVERSIZED INLET LINE: White Knight (as well as many other air driven
pumps) are best installed with liquid inlet lines larger than the liquid outlet
lines, particularly in open loop systems where there is very little head
pressure. This reduces strain on bellows and diaphragms and also in many
cases reduces surge in the outlet line from the pump.

PULSATION: White Knight pumps are famous for the low surge created in
outlet lines down stream from the pump. However, there are things that can
be done to reduce surge even further. White Knight offers Flatliner

Pulsation dampeners in various sizes to minimize surge created by air driven
pumps. In open loop systems where there is very little head pressure, most
White Knight customers find it unnecessary to use additional pulsation
dampening devices, however, as head pressure increases, the requirement
for pulsation dampening increases. A less expensive way to lessen pulsation
in the outlet line is by the usage of a “stand tube”. This is accomplished by
installing a Tee in the outlet line from the pump. The Tee is pointed upward
and a piece of tubing (typically 3-4 feet long) is stood up and capped. As the
pump runs, the liquid pressure in the line compresses the air in the stand tube
during the pressure part of the pump stroke and the compressed air in the
stand tube pushes liquid back into the line during the shift part of the pump