11
The optional seal chamber, mechanical seal gland, and pump
casing jackets may be used to provide pump heating. The jack-
ets are good for pressure to 125 psig and may be used with
steam or heat transfer liquids. Series or parallel piping of the
seal chamber and pump casing jackets may be used. The
mechanical seal gland jacket piping should be run indepen-
dently so as not to be a flow restriction.
When steam is used as the heating medium, inlet piping should be
run to the highest jacket connection and outlet should be from the
lowest connection to allow condensate to drain.
The casing and backhead may be lagged to minimize heat loss.
Remember that seal chamber temperatures above 350°F may
cause early failure of mechanical seal parts.
PUMP HEATING REQUIREMENTS
Lubrication of the ball type bearings in Dean pumps is by oil
contained in the sump of the bearing housing (26). The oil must
be a good grade of rust and oxidation inhibited, non-foaming,
industrial oil with a viscosity of approximately 500 SSU at
100°F. This will be an ISO 100 oil.
Failure to level the pump assembly when the entire unit is
installed may adversely affect the oil level and reduce bearing
life. Proper care should be taken to avoid this condition.
The pump is fitted with a “Bull’s Eye” type oil level indicator, and fill
openings on both sides of the bearing housing. If it would be easier
to see, the “Bull’s Eye” can be removed and repositioned on the
opposite side of the bearing housing. Fill the sump through one of
the NPT fill openings on the side of the bearing housing until the oil
level reaches the center of the “Bull’s Eye” level indicator. The oil
must be maintained at this level during operation.
If the optional automatic oiler was supplied, it was packed sepa-
rately for pump shipment to avoid damage. Install the oiler into the
1” NPT tapped hole on either side of the bearing housing. Screw
the oiler reservoir from the top of the “Bull‘s Eye” housing, invert it,
fill it with oil, and reinstall it into the housing.
The oil should be drained and replaced at regular intervals, the
intervals depending on the atmospheric conditions (dust, soot, cor-
rosive vapors, humidity, temperature variations, etc.) prevailing at
the pump installation site. The bearing housing should be flushed
with a good solvent before the oil is replaced.
Pumps are shipped from the factory without oil in the bearing housing.
It is important that a pump should never be subjected to thermal or
pressure shock. The liquid should therefore be allowed to flow into
the casing slowly. A centrifugal pump should never be started until
all the parts are up to the temperature of the liquid to be pumped.
If the pump is equipped with cooling water piping this should be
turned on before filling the pump.
FILLING
WARNING:
Before filling the pump with liquid, check to see that all possible leak
locations are sealed. See that the point where the pump shaft enters
the pressure containing cavity is sealed. Normally this sealing is
accomplished with shaft packing or a mechanical face seal. See that
all of the connections into the pressure containing cavity are sealed
or connected to a related piping system that also has all possible
leak paths sealed. Do not plug unused jacket cavities, as this could
develop dangerous pressure build-up. Use a wrench on all bolted
joints to apply torque to assure that all gaskets are sealed in a tight
joint. Check to see that all threaded pipe connections are also tight
enough to seal the Liquid pressure that will be applied when the sys-
tem is started.
When the source of liquid supplied to the pump is below atmospher-
ic pressure or located below the pump, the pump must be primed
prior to start up. The priming may be ac complished in any of several
ways, three of which are listed.
1) An exhauster may be connected to the discharge piping
between the pump and the discharge shut-off valve. With the
discharge shut-off valve closed and the suction valve open, the
air can be exhausted from the pump and piping.
2) With a foot valve installed in the suction piping, the pump may
be filled with liquid introduced somewhere above the pump in
the discharge line. The seal chamber should be vented to allow
complete filling. A foot valve may create extensive losses and
should be taken into consideration in calculating the available
NPSH.
3) A vacuum pump (preferably a wet vacuum pump) may be used
for evacuating air from the pump and piping. The vacuum pump
should be connected as is the exhauster covered in No. 1.
When the source of liquid supplied to the pump is above atmospher-
ic pressure or above the pump centerline, the pump may be filled by
venting through a bleed off line to atmosphere or back to the pump
suction source.
It is most important to check the direction of rotation of the pump
before allowing the pump to come up to speed. To check rotation
direction, push the starting button and instantly push the stop button.
This will allow the motor to turn over a few revolutions and the direc-
tion of rotation to be observed. If the pump is fitted with the optional
“C” face motor support (83), the shaft coupling will be installed,
causing the pump shaft to rotate with the motor shaft. Be careful that
you push the start and stop buttons essentially at the same time so
that the unit does not come up to speed. The impeller is threaded on
to the pump shaft, and will unscrew causing damage if operated in
reverse direction. A direction of rotation arrow is shown on the front
of the pump casing. If rotation is incorrect, change the wiring con-
nections and recheck rotation. Operating the pump in reverse rota-
tion may cause extensive damage.
WARNING:
Lock-out the power to the driver (motor, turbine, engine, etc.)
Install the shaft coupling spacer. Be sure that you install all the
retaining devices and bolts and that they are tight. Read and comply
with the coupling manufacturers instructions. Personal injury, death,
and/or equipment damage could occur if the coupling spacer is not
properly installed. Remove all debris and tools from the area near
the shafts and the shaft coupling. Do this to assure that nothing is
STARTING THE PUMP
PUMP LUBRICATION
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