Instruction 2111.80B 04/05 11
before the pump starts. A flow meter or flow indicator installed on the seal water line will verify flow of
seal water into the seal box. A pressure reducing valve and needle valve can be used to adjust
pressure and flow rate.
b. Closed Loop Filtered Lubrication System
The mechanical seal is lubricated by liquid taken directly from the pump discharge. The liquid enters the
seal chamber from the power frame end. The double seal housing should be vented using the
petcock prior to starting the pump. This will insure that no air is trapped within the mechanical
seal chamber. CAUTION: Never run the mechanical seal dry as damage will result. The liquid used
for lubrication must be filtered prior to being used. Therefore, the liquid drained through the petcock
should be clean. If sand is present in this liquid the filter insert requires replacement. If the liquid from
the petcock is dark in color, check the seal faces and replace entire seal if one or more seal faces are
damaged. Liquid leaking out the end of the mechanical seal housing indicates that a re-application of a
non-hardening gasket compound must be made.
As the seal is a precision made product, care must be taken in handling. The carbon and ceramic
parts should be safeguarded from drops or severe blows. Particular care should be taken to avoid
scratching the capped surfaces on the washer and floating seal.
Other
Refer to specific manufacturer's instructions for lubrication recommendations for drives, motors or other accessories.
C. PREPARATION FOR START-UP
Prior to initial start-up of the pump, the following items must be checked:
1. Be sure that all equipment is properly aligned and has been lubricated in accordance with the PRE-
STARTUP LUBRICATION INSTRUCTIONS, pages 9 through 11.
2. Turn shaft by hand to see that it rotates freely. If it binds, or turns with difficulty, refer to "Repairs" section
of this manual for guidance to remedy the problem.
3. Be sure that discharge pressure gauges and suction compound gauges are properly installed and
operating.
4. Verify that current characteristics of voltage and frequency on the driver nameplate coincide with the service
provided.
5. Check to see that the direction of rotation is the same as shown by the arrow on the pump and on the
installation drawing. To check rotation, quickly turn the power on and off (only long enough to get the shaft
spinning). Observe the direction of rotation of the coupling. The motor leads should be marked, and the
starter diagram located inside the starter should be marked, so that the connections can be broken and
remade with accuracy. It is important that the pump rotates in the direction for which it was designed. If the
pump is not rotating in the direction the pump is intended, interchange any two of the motor leads and
recheck. As soon as the pump is rotating in the correct direction, mark the leads and diagram as
mentioned above. These instructions apply to three phase motors only. Single phase motors cannot be
reversed in this manner and are checked at the factory. If rotation reversal is required for single phase
motors, consult the factory.
6. Verify that all thermal units are closed and the H-O-A switch (when used) is in the “off” position.
7. Refer to driver and control manuals for specific pre-start instructions.
8. Verify that the gate valve on the discharge line is closed and the suction valve is completely open.
A centrifugal pump, primed and operating at full speed with the discharge valve closed, usually
requires less power than when operating at rated head and capacity with the discharge valve open. For
this reason CHICAGO PUMP recommends that whenever practical, the discharge gate valve be closed
when starting the pump.
To prevent overheating, "shut-off' operation should be limited to five minute periods. Prolonged "shut-off'
operation may prove harmful to the structural integrity of the pump mainly because of increased vibration
level affecting the bearings and stuffing box or mechanical seal; increased radial thrust and resultant stress in
the shafts and bearings; or excessive cavitation and accompanying damage resulting from internal re-
circulation.
WARNING
OPERATION OF A CENTRIFUGAL PUMP WITH THE SUCTION VALVE CLOSED AND THE DISCHARGE VALVE
OPEN, OR BOTH VALVES CLOSED MAY CAUSE SERIOUS DAMAGE TO THE PUMP. SUCH OPERATION MAY
LEAD TO RAPID AND VIOLENT PUMP FAILURE.
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