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3-1-618 Page 7
SECTION 2
OPERATING AND MAINTENANCE INSTRUCTIONS
INSTALLATION
LOCATION -
Pump should be located as close to the
fluid supply as possible. A short and direct suction
line will improve pump performance and reduces the
possibilities of cavitation. Whenever possible,
adequate space should be provided around the pump
to permit easy inspection and adjustment. Particular
attention should be given to the space required for
removal and installation of the gear reducer,
eccentric, etc.
The drive must be accurately aligned. Pump must be
properly leveled and securely fastened to a
foundation or base. The pump must have a positive
suction head. Refer to page 19 for NPSH
requirements. Maximum allowable temperature of
the fluid being pumped is 180
°
F (82
°
C). The
maximum allowable suction pressure is 75 PSI. Any
application with suction pressures over 75 PSI must
be approved in writing by Gardner Denver Inc.
Engineering Department.
SUCTION PIPING
- Suction pipe (or hose if used)
should be the full size of suction opening. If, for any
reason, the suction line is of greater length than
usual, the next larger size should be used. Suction
line should slope up towards the pump at a uniform
grade so that air pockets are eliminated. Suction line
must be air tight as any air leaking into the line will
reduce the volumetric efficiency of the pump. If it is
necessary to have bends in the suction line, they
should have long radius sweeps.
Refer to page 18 for recommended suction piping
system. All piping must be supported independently
of the pump to insure that no strain is imposed in the
pump by misalignment or improperly fitted pipe.
PRESSURE RELIEF VALVE –
The pump must be
protected from excessive discharge pressure by a
pressure relief valve. This valve must be installed as
near to the pump discharge manifold as possible.
The pressure relief valve should be set to operate at
approximately 1.1 to 1.25 times the discharge
pressure, depending on the relief valve
manufacturer’s recommendations, but this setting
MUST NOT exceed adjoining system equipment
rated pressure capabilities. The relief valve must be
sized to accept the full pump flow per the valve
manufacturer’s instructions.
When the pump is equipped with a shear pin type
pressure relief valve, use only the shear pin specified
in the relief valve manufacturer’s instructions. Do
not use allen wrenches for shear pins, or hammer on
the shear bar stem, or shear bar slot. For complete
installation and maintenance instructions refer to the
relief valve manufacturer’s catalog and/or instruction
manual.
WARNING
Never install a shutoff valve in the line
between the pressure relief valve and the
pump cylinder, as pumping against a
closed valve could produce pressures
sufficient to cause property damage and/or
serious personal injury or death.
DANGER
Improper use or maintenance of pressure
relief valves can cause excessive pressure
which may result in property damage
and/or serious personal injury or death.
DANGER
Never install a shutoff valve in the line
between the pressure relief valve and the
pump cylinder, as pumping against a
closed valve could produce pressures
sufficient to cause property damage and/or
serious personal injury or death.