The top edge of the bowl top has a retaining groove
into which is inserted an oil-resistant rubber seal ring.
This ring is a flat rubber washer, not an 0-ring. A
discharge ring seats on top of this seal ring.
The outer edge around the top of the bowl top is
threaded to receive a coupling nut. The coupling nut
screws down over the discharge ring, forcing the dis-
charge ring down onto the rubber seal ring. This seal
ensures that discharging water will flow up through the
center of the discharge ring.
The coupling ring, as previously stated, forces the
bowl top down onto the top of the bowl shell, thus
completing a seal. As the coupling ring is screwed
downward, it forces the bowl top down onto the disk
stack. This action compresses the disk stack and ensures
that each disk will seat tightly on its adjacent disks. The
space between each disk is thereby assured to be correct.
To ensure correct tension on the disk stack, an
aligning mark is stamped on the coupling ring and the
bowl top. These two marks must be lined up when
tightening the coupling ring. An indicating arrow and
the word OPEN are also stamped on top of the cou-
pling ring. These marks show the direction of rotation
to remove the coupling ring.
The coupling ring and coupling nut have
Four T-shaped slots are equally spaced around the
outside/upper rim of the coupling ring. A special
wrench engages these slots for removal or installation
of the coupling ring.
A discharge ring, seated on top of the bowl top, acts
as a dam to maintain the proper line of separation
between the water and the JP-5 within the bowl shell
Each purifier is furnished with a set of seven dis-
charge rings. The outside diameters of the discharge
rings are the same. The inside diameters of the discharge
rings are different. The inside diameter size is etched on
each ring. The inside diameters range from 220 milli-
meters to 250 millimeters in 5-millimeter increments
(220, 225, 230, 235, 240, 245, and 250).
The coupling nut locks the discharge ring in place.
Like the coupling ring, the coupling nut also has an
indicating arrow and the word OPEN stamped on its
The coupling nut has four circular slots equally
spaced around its outer edge. A special wrench en-
gages one of these slots for removal or installation.
The operations described in this section deal with
starting from two different conditions-with a clean bowl
and with a dirty bowl.
Regardless of the condition of the bowl, there are
some preliminary steps to follow before starting the
purifier. These steps are as follows:
1. Open the bowl cover.
2. Ensure the handbrake is in the OFF position.
3. Remove the two bowl shell lock screws.
4. Insert the two bowl shell lock screw plugs.
5. Turn the bowl by hand. If the bowl does not
turn freely, investigate and correct the cause.
6. Check the level of oil in the oil sump. If the oil
is at or below the red line, add sufficient oil to raise the
oil level to the white line.
7. Close the bowl cover and engage and tighten
the three handwheel cover clamps.
8. Engage the feed tube to the paring disk.
9. Ensure the seal water inlet hose is connected to
the purifier seal water inlet valve.
10. Ensure the purifier sump tanks are empty.
The following starting and stopping procedures
are for transferring fuel from one port wing storage
tank, through one transfer pump, through the port
purifier, to one port wing service tank. Since transfer
is from wing tank to wing tank within the same group
of tanks, and on the same side of the ship, there is very
little change to the list and trim of the ship. The
starboard service tanks can be filled from starboard
storage tanks in the same manner. But, the transfer-
ring is accomplished by using only one transfer pump
to pump into one purifier, since they both have the
Starting with a clean bowl is accomplished as
1. Close the following valves:
a. Sample connections.
b. Purifier inlet valve.
c. Purifier discharge valve.
d. Purifier seal water inlet valve.
2. Open the following valves:
a. Designated manifold tankside valve.