Zenith BB-PEP Series, Original Installation, Care And Maintenance, Page: 8 / 16

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J. CLEANING PUMP FOR DISASSEMBLY
CAUTION ATTENTION
BB-PEP pumps are precision pumping devices made to close tolerances and will provide excellent service
if applied correctly, handled carefully, and maintained. While the pump is composed of steel, it is a
precision instrument. Dropping the pump or hitting with a non-yielding material can cause serious damage
to the components. All materials are through-hardened to maximum hardness resulting in brittle material.
Treat them as you would any other precision gauging instrument.
The pump normally has to be cleaned for ease of disassembly. This can involve simply flushing the pump or a vacuum
oven burnout at a maximum temperature of 900°F (482°C) in a protective atmosphere. Soak the pump in solvent (TEG
for example for polyester) or heating to a moderate temperature of 300° to 600°F (150° to 315°C) to melt the process
fluid and allow most of it to be flushed out of the pump. If a vacuum oven is available, the pump may be heated to higher
temperatures to carbonize the polymer within the pump. Contact the factory for proper burnout temperatures.
Another acceptable cleaning method is to immerse the pump in a fluidized bed cleaning bath. The bath should be
heated to a temperature that is sufficient to carburize the polymer. The carburization process usually takes between 3 to
12 hours, depending on the polymer type, temperature, pump size, and furnace load.
CAUTION ATTENTION
Avoid exposing the pump to thermal shock when using this method of cleaning.
After gradually cooling to room temperature, the pump should be thoroughly flushed in a clean solvent. It may be
necessary to disassemble the seal arrangement to remove polymer ash.
If the pump was performing satisfactorily when removed from service and still turns freely after burnout, pressure test it
and add a high-temperature lubricant to prepare it for return to service. To store for future use, simply add rust
preventative oil.
It is recommended that pump users institute a program of dimensional inspection of critical parts in order to keep
maintenance and operating costs at a minimum. By noting the performance of a pump immediately before removing it
from service and correlating the performance to the measured component wear, the user can establish the maximum
wear limits for the pump’s critical components. Further, he can predict the service life of the pump, and schedule
downtime accordingly.
As with any other Zenith pump, BB-PEP Series pumps may be returned to Zenith for complete rehabilitation as
necessary. This procedure may be desirable if only a few pumps are involved. Zenith offers a contract service program
to repair and maintain your pumps. If a large number of pumps are to be maintained at the user’s plant, it may be
worthwhile to have key personnel attend a maintenance seminar at the Zenith factory to view the manufacturing,
gauging, and assembly techniques involved in producing the BB-PEP Series pumps. Please contact Zenith for further
information on contract repair service program or Maintenance seminar offerings.
In some cases spraying or soaking the pumps with one of several available penetrating oils can facilitate disassembly.
Once cleaned, the pump is ready for disassembly.
K. DISASSEMBLY OF PUMP
CAUTION ATTENTION
Zenith pumps require careful maintenance and handling, especially of component parts. The slightest burr,
nick or particle of foreign matter can cause scoring or even seizure. Zenith pumps are precision
instruments; you can't keep them too clean! Please treat them with care, and if it’s at all possible, set aside
a separate clean area for pump maintenance.