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11
1.0 Components
1.1 Filter Body
Manufactured from stainless steel 304L, the filter body consists of six pods each containing
a filter element and joined by a common inlet and outlet. Also connected to the central
chamber of the filter is the backwash pipe. The inlet and outlet connections are 3” flange,
ANSI 150 bolt hole pattern, and the backwash connection is 3/4” NPT female.
1.2 Motor/Gearbox
The motor/gearbox is fitted on top of the Indexing Valve. The motor/gearbox rotates the
Indexing Valve 360º while backwashing each pod in sequence.
1.3 Opto Disc
A slotted disc is fitted to the top of the motor/gearbox drive shaft, to provide indication to the
circuit board by means of two optical sensors the position of the Indexing Valve.
1.4 Indexing Valve
The Indexing Valve is situated in the central inlet chamber. The motor/gearbox drives this
valve. During backwash, the Indexing Valve rotates to close off the inlet to each pod in
sequence while simultaneously providing access to the
¾
” backwash port. Fitted on the
backwash line is a pneumatically operated Backwash Valve that opens and closes with
each index position. The opening of the Backwash Valve allows a reverse flow of clean
liquid to open each element in sequence while flushing the accumulated debris from the
filter element to drain.
1.5 Backwash Valve
The Backwash Valve is pneumatically operated. In the filter position, the valve is closed
and prevents liquid loss from the backwash line. During backwash, the valve opens and
closes with each index position. If there is a fault with the filter (see Section 5.0), the
backwash valve will automatically close.
1.6 Element Selection
Element selection is dependent on the nature of the contaminant in the fluid to be filtered.
As can be seen from the flowchart in Exhibit 1, the smaller the micron size the lower the flow
rate through the filter. Correspondingly, this will also directly affect the clean differential
pressure across the filter.