21
Pump
Diaphragm pumps are a positive displacement
pump that utilise a number of rubber
diaphragms and non-return check valves to
pump (displace) the fluid. Diaphragm pumps
are very well suited to chemical spraying
applications. To ensure that you get the most
from your pump, follow the information here to
use it correctly. Proper operation and periodic
maintenance are essential in obtaining the
best possible performance from your sprayer
over time.
PRESSURE RELIEF VALVE
The pressure relief valve provides relief when
the pressure exceeds a pre-determined
value and is part of the pressure control unit.
Turning the adjuster clockwise will increase
the pressure relief setting and vice versa. The
pressure gauge gives indication of the delivery
pressure to the spray gun.
BYPASS VALVE
The bypass valve enables all pump delivery
to bypass back to the tank. The bypass valve
is part of pressure control unit. It should
be opened when starting the pump with
an engine so that the engine does not start
under load. The bypass valve should also be
engaged to agitate the tank mixture when not
spraying. To engage the bypass valve, pull
the valve lever out. This will cause all pump
delivery to be bypassed back to the tank. To
disengage the bypass valve, push the valve
lever in, so that the pump delivery is directed
out to the spray lines.
IMPORTANT:
Never overfill pump with oil as
damage to seals & oil bowl may result. Do not
operate diaphragm pumps above 540 RPM.
IMPORTANT:
The pump will perform optimally
close to, but not over 540 RPM. At speeds
much below 540 RPM, excessive pulsation will
occur. Speeds above 540 RPM are likely to
result in pump and diaphragm damage.
IMPORTANT:
Do not leave water in pump if
sprayer is to be left in a cold environment.
Frozen water inside the pump can cause
the housing to crack. Always allow any
frozen water inside the pump to thaw before
attempting to operate the pump.
PREOPERATIONAL PROCEDURE
1.
If sprayer is in a cold environment, make
sure that any frozen water present in
the pump is thawed before attempting
operation to avoid serious damage.
Ensure that the pump can be turned over
by hand before starting.
2. Inspect all hoses to make sure they are
the correct size, fitted securely and that
there is no restriction or leaking.
3. Make sure that the pump PTO shaft cover
is fitted correctly to prevent accidental
injury.
4. Make sure the strainer in the suction filter
is clean and correctly installed.
5. Lubricate the PTO shaft according to
manufacturer recommendations to
prevent the shaft from binding.
6. Change the pump oil after the first 50
hours of operation and then after every
300-350 hours. Use only SAE 30W40
motor oil and do not overfill. Rotate pump
manually (by hand) to remove air locks
when filling with oil.
WHEN THE PUMP IS OPERATING
•
The oil should be visible in the bowl.
•
Frequently check the oil level and colour.
IMPORTANT:
A change in either colour or level
indicates probable damage to diaphragm or
valves.
Stop the pump immediately.
POST OPERATIONAL PROCEDURE
1.
Always flush pump with clean water at
the end of each spraying day. Prolonged
chemical contact can severely damage
seals and diaphragms.
2.
Do not leave water in pump if sprayer is
to be left in a cold environment. Frozen
water inside the pump can cause the
housing to crack. Empty pump of all
water and run it dry for 15-20 seconds
Then cover pump with a bag or similar
to keep it protected. If this has not been
done and there is a possibility there may
be frozen water in the pump and/or in the
lines, wait until any ice has completely
thawed before using pump again.
