Principle of pump operation, Installation – Blagdon Pump X15 FDA User Manual
Page 5
HG-CF-1123 Rev. D - 10.12.09
Page 5
PRINCIPLE OF PUMP
OPERATION
This ball valve type diaphragm pump is
powered by compressed air and is a 1:1 ratio
design. The inner side of one diaphragm
chamber is alternately pressurised while
simultaneously exhausting the other inner
chamber. This causes the diaphragms, which are
connected by a common shaft secured by plates
to the centres of the diaphragms, to move in a
reciprocating action. (As one diaphragm
performs a discharge stroke the other diaphragm
is pulled to perform the suction stroke in the
opposite chamber.) Air pressure is applied over
the entire inner surface of the diaphragm while
liquid is discharged from the opposite side of
the diaphragm. The diaphragm operates in a
balanced condition during the discharge stroke
which allows the pump to be operated at
discharge heads of over 200 feet (61 meters) of
water.
For maximum diaphragm life, keep the pump as
close to the liquid being pumped as possible.
Positive suction head in excess of 10 feet of
liquid (3.048 meters) may require a back
pressure regulating device to maximize
diaphragm life.
Alternate pressurising and exhausting of the
diaphragm chamber is performed by an
externally mounted, pilot operated, 2 way type
distribution valve. When the spool shifts to one
end of the valve block body, inlet pressure is
applied to one chamber and the other diaphragm
chamber exhausts. When the spool shifts to the
opposite end of the valve body, the pressure to
the chambers is reversed. This alternating
movement of the spool inside the valve body is
controlled by a pilot air pressure signal held
against the diaphragm shaft, between seals in the
diaphragm shaft bushes. This signal is released,
triggering the movement of the spool, when pilot
holes in the diaphragm shaft align with the held
pilot signal, sending the signal to exhaust, which
in-turn causes a pressure imbalance around the
spool, sending it to the opposite end of the valve
body. This simultaneously sends inlet pressure
to the opposite chamber.
The chambers are connected by manifolds with a
suction and discharge ball valve for each
chamber, maintaining flow in one direction
through the pump.
INSTALLATION
The typical installation shown in FIG. 1 is only a
guide to selecting and installing system
components. Your installation will depend on
the type of fluid being pumped and your
application needs. To reduce the risk of serious
bodily injury and damage to property, never use
fluids in this pump which are not compatible
with the wetted components. Contact your local
distributor or the manufacturer for system design
assistance & compatibility if necessary.
Mount the pump in an upright position. Failure
to ensure an upright position may result in loss
of or poor priming characteristics. Ensure the
pump is securely mounted to avoid movement
and possible risk of bodily injury.
PRESSURE The pump delivers the same
pressure at the discharge outlet as the air
pressure applied at the air inlet (unless pump is
configured as a 2:1 ratio model).
NOTE: Pressure Regulator (H) should be
installed where air supply could exceed 125
psi.
SAFETY
Your BLAGDON PUMP is a high
performance unit capable of achieving
high outputs at high efficiencies. However, as
is common with pneumatic equipment, the
pump efficiencies is reliant upon the air being
clean, dry and filtered. Failure to comply with
these requirements may lead to loss of
performance and reduced component life and in
extreme cases, permanent damage to the pump.
To avoid leaks, ensure that all fluid connections
are tight. The use of PTFE thread tape correctly
applied should be used to ensure 100% leak
proof connections. Failure to ensure 100%
sealability of the suction connection could
adversely affect suction performance.
If you are pumping hazardous fluids, or
operating the pump in an enclosed area, it is
essential that the exhaust from the pump is
piped away to a safe location. When pumping
hazardous fluids the above instructions must be
adhered to in order to ensure safe operating
procedures. (Under certain operating
conditions the failure of internal components
can lead to the pumped fluid being exhausted
via the pump exhaust outlet).
WARNING
NEVER place your hands over or near the
pump suction inlet. Powerful suction could
cause serious bodily injury.
FLUSH THE PUMP This pump was tested
with water containing an oil-based rust
inhibitor. If this solution could contaminate or
react with the fluid you are pumping, flush the
pump thoroughly with a solvent/detergent to
clean internal components. The solvent/
detergent must be compatible with the pump
materials of construction. Care should be taken
to flush the pump each time it is disassembled
for maintenance or repair.
CAUTION
All BLAGDON PUMPS are built lubricated
with grease during assembly and need no
further lubrication. If the use of oil cannot be
avoided, this will not present any problems. A
light No. 2 class lithium grease is
recommended. Other grades may cause the Air
Logic System to operate intermittently, thereby
causing a loss of output and failure to operate.
Other seals are available for “clean room”
conditions
If the pump accelerates or is running too fast
due to a lack of fluid, then stop it immediately
by shutting off the air supply. A dry pump will
accelerate to a high speed causing wear to
elastomers.
If the fluid you are pumping tends to dry up or
set when it is not moving, then flush the pump
as often as necessary to prevent the fluid from
drying in the pump. Drain the pump thoroughly
before storing.
If feasible, invert pump to allow any fluid to
drain from the non-return valves
.
AIR
Exhaust
1
3
2
4
Flexible
Connection
Pipe Connection
(Style Optional)
Gauge
Shut-off
Valve
Drain Port
DISCHARGE
Pulsation
Dampener
Regulator/Lubricator
Air Shut-Off
Valve
Air Dryer
INLET
Air Inlet
Air Exhaust
Pipe Connection
(Style Optional)
Air
Gauge
Shut-off
Valve
Drain Port
SUCTION
Filter
Connection
Flexible
Installation Guide
Fig. 1
Available from
Blagdon Pump :-
1. Pulsation Dampener
2. Filter/Regulator
3. Lubricator
4. Air Dryer
CAUTION !
The air exhaust should be piped
to an area for safe disposition of
the product being pumped, in the
event of diaphragm failure.