Pag.15 (Funct. and Maint.Manual n.03 – Fourth edition) OMI.EN-PCP001 R01
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Disassemble the pump and wash every part of it with suitable detergent. Re-
assemble the parts making sure they stay clean.
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Perform Cleaning in Place (CIP) if the pump is suitable for this kind of cleaning.
7.2.1 When to perform cleaning
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Before startup
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After a prolonged stop
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After replacing parts
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After use if a prolonged stop is foreseen
Several companies supply products for CIP cleaning. Make sure the products used are
compatible with the material to be pumped.
7.2.2 CIP cycle
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Pre-washing with clean water, to empty the pump
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Basic washing with caustic soda (1-2% at 60-80°C for 10-20 min.)
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Intermediate washing with clean water for 5-10 min.
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Washing with nitric acid (1-1.5%) at 50-70° C for 5-10 min.
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Final washing with clean water for 5-10 min.
Note: The washing speed of liquid detergents should not exceed 2 m/s at any point.
In this cycle the stator is subject to high chemical and thermal stress. Therefore, in this CIP
cycle the pump shall stop and restart, that is, change the relative position of rotor and
stator every 2-3 minutes, turning just a few times to make sure that every part of the stator
gets cleaned.
7.3 Temporary rest
After stopping the pump, empty it and possibly wash it if:
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The fluid may solidify.
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The mechanical seal may get encrusted.
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The liquid inside the pump may freeze due to the low ambient temperature.
7.3.1 Procedures
7.3.1.1 Stator
In case of prolonged stop, the rotor may permanently deform the stator on the contact
surfaces (compression-set). In this case a greater pickup torque is required at restart.
It is therefore better to dismount the stator from the pump, pack it to shelter it from air and
light and store it in a cool, dry place.
7.3.1.2 Rotor
After the stator has been disassambled, rest the rotor on wooden blocks and cover it to
prevent damage.
Before reassembly, degrease and clean the rotor to prevent conflicts with the stator
material or with the product to be pumped.
