T R O U B L E S H O O T I N G
S U G G E S T E D O P E R A T I O N & M A I N T E N A N C E
WIL-11112-E-01
9
WILDEN PUMP & ENGINEERING, LLC
OPERATION: The HS400S is pre-lubricated, and does
not require in-line lubrication. Additional lubrication
will not damage the pump, however if the pump is
heavily lubricated by an external source, the pump’s
internal lubrication may be washed away. If the pump
is then moved to a non-lubricated location, it may need
to be disassembled and re-lubricated as described in
the DISASSEMBLY/REASSEMBLY INSTRUCTIONS.
Pump-discharge rate can be controlled by limiting
the volume and/or pressure of the air supply to the
pump. An air regulator is used to regulate air pressure.
A needle valve is used to regulate volume. Pump-
discharge rate can also be controlled by throttling
the pump-discharge by partially closing a valve in
the discharge line of the pump. This action increases
friction loss which reduces flow rate. (See Section 5.)
This is useful when the need exists to control the pump
from a remote location. When the pump discharge
pressure equals or exceeds the air supply pressure,
the pump will stop; no bypass or pressure relief valve
is needed, and pump damage will not occur. The
pump has reached a “deadhead” situation and can
be restarted by reducing the fluid discharge pressure
or increasing the air inlet pressure. The Wilden
Pro-Flo
®
SHIFT pumps run solely on compressed air
and do not generate heat, therefore your process fluid
temperature will not be affected.
MAINTENANCE AND INSPECTIONS:
Since each
application is unique, maintenance schedules may
be different for every pump. Frequency of use, line
pressure, viscosity and abrasiveness of process fluid
all affect the parts life of a Wilden pump. Periodic
inspections have been found to offer the best
means for preventing unscheduled pump downtime.
Personnel familiar with the pump’s construction and
service should be informed of any abnormalities that
are detected during operation.
RECORDS: When service is required, a record should
be made of all necessary repairs and replacements.
Over a period of time, such records can become a
valuable tool for predicting and preventing future
maintenance problems and unscheduled downtime. In
addition, accurate records make it possible to identify
pumps that are poorly suited to their applications.
Pump will not run or runs slowly.
1. Ensure that the air inlet pressure is at least 0.4 bar
(5 psig) above startup pressure and that the
differential pressure (the difference between air inlet
and liquid discharge pressures) is not less than 0.7
bar (10 psig).
2. Check air inlet filter for debris (see SUGGESTED
INSTALLATION).
3. Check for extreme air leakage (blow by) which would
indicate worn seals/bores in the air valve, pilot spool
and main shaft.
4. Disassemble pump and check for obstructions in the
air passageways or objects that would obstruct the
movement of internal parts.
5. Check for sticking check valves. If material being
pumped is not compatible with pump elastomers,
swelling may occur. Replace check valves with
proper elastomers.
6. Check for broken inner piston, which will cause the
air valve spool to be unable to shift.
7. Remove plug from pilot spool exhaust.
Pump runs, but little or no product flows.
1. Check for pump cavitation; decrease pump speed to
allow thick material to flow into liquid chambers.
2.
Verify that vacuum required to lift liquid is not
greater than the vapor pressure of the material being
pumped (cavitation).
3. Check for sticking check valves. If material being
pumped is not compatible with pump elastomers,
swelling may occur. Replace check valves with
proper elastomers.
Pump air valve freezes.
1.
Check for excessive moisture in compressed
air. Either install a dryer or hot-air generator for
compressed air. Alternatively, a coalescing filter
may be used to remove the water from the
compressed air in some applications.
Air bubbles in pump discharge.
1. Check for ruptured diaphragm.
2. Check tightness of outer pistons (refer to Section 7).
3. Check tightness of fasteners and integrity of O-rings
and seals, especially at intake manifold.
4. Ensure pipe connections are airtight.
Product comes out air exhaust.
1. Check for diaphragm rupture.
2. Check tightness of outer pistons to shaft.
