Installation
Waukesha Cherry-Burrell
®
Brand Universal 3 Pump
Page 22
95-03103
02/2021
Seal Flush Connections
Double Mechanical Seals
Pumps with double seals require flushing.
The flush media (water or lubricating fluid compatible with the
product) must be connected and flowing whenever the pump is
operated.
Two 1/8-inch female pipe thread (NPT) flush connections are
located in the seal housing pieces.
1. Connect the flush inlet to the lower connection, and the outlet
to the upper connection, to flood the flush area completely
(Figure 20).
2. Connect the flush outlet for unrestricted flow to the drain.
NOTE:
As shown (ports horizontal), if
steam
is used as a
flush media, connect the inlet at the upper connection, and
the outlet at the lower connection to ensure condensation
removal (Figure 21).
If
steam condensate
is used as a flush media, connect the
inlet at the lower connection, and the outlet at the upper
connection (Figure 20). See note under Figure 22.
3. Use cool, filtered flush media to obtain maximum service life
of the seal components. If the pumped product is sticky or
solidifies at room temperature, use warm or hot flush media.
4. Install a pressure reducing valve and flow control valve (nee-
dle valve) on the flush supply line. Set the supply pressure at
a maximum of 220 psi (15 bar). The required flow rate is 0.5-
0.8 gpm (1.9-3.0 l/m).
NOTE:
The difference between the product-side pressure
and the flushing pressure must not exceed 102 psi (7 bar).
5. Also install a solenoid valve in the flush supply and wire it in
series with the motor starter to provide an automatic start/
stop of the flush media flow before the motor turns on and
after the motor turns off.
Double O-Ring Seals
1. Set flow rate of approximately 1/4 gpm for most applications.
For high temperature applications, increase flow.
2. Flushing media is restricted on the inlet side and has free
flow to drain on the outlet side.
3. Typical flushing connections are 1/8" NPT female pipe taps.
NOTE:
For O-ring seals, the maximum product pressure is 100
psi (7 bar).
Figure 20 - Flush Piping - Liquid,
Steam Condensate
PD100-661
Flush In
Liquid,
Steam
Condensate
Liquid,
Steam
Condensate
Flush Out
WARNING
Operating the pump without flush will damage the seal and pump
parts due to excess heat from dry running.
CAUTION
Check for buildup or restrictions (kinking) in the flush lines or
fittings at regular intervals. SPX FLOW recommends using clear
(transparent) flush lines for easier observation.
Figure 21 - Flush Piping - Steam
Figure 22 - Flush Piping - Liquid,
Steam, Steam Condensate
NOTE:
If ports are vertical (pump is side-
mounted, not shown): Liquid/steam
condensate: In bottom, out top
Steam: In top, out bottom
PD100-661a
Flush Out
Steam
Steam
Flush In
PD100-661b
Flush In
Flush Out
Flush Out
Flush In
High Pressure Flush
Low Pressure Flush
Figure 23 - Flush Piping Setup
OUT
Gauge
Solenoid
Valve
Valve
Pressure
Restrictor
IN
IN
OUT
Restrictor
Valve