Replacement Of Porcelain Insulators - CleaverBrooks CEJS Installation, Operation And Maintanance

Electrode Boiler

9.5-Replacement of porcelain insulators

1.Turn off all power to the boiler, drain the pressure vessel completely, and allow it to cool. Boiler
should not be heated/cooled quicker than 3-5 F per minute to protect the porcelain insulators from
damage.
2.Securely support the electrode box inside the vessel. Remove the high voltage cable(s) and loosen
the electrode rod nut. Remove the rod assembly carefully, taking care not to crack or chip the insulators
or damage the assembly in any way (details in the following pages).
3.Clean and inspect the Pyrex tube for cracks and replace if necessary.
4.Replace the damaged porcelain insulator and reassemble the electrode with new gaskets.
5.Replace the electrode in the boiler and reinstall the shield and the electrode plate and housing inside
the vessel, again taking care not to damage the electrode. Check the clearances and dimensions for
the assembly against the boiler drawings to ensure that the electrode has been positioned properly.
Tighten the electrode rod nut to 500 ft-lb, making sure the rod does not rotate. See Figures 11 and
12 for electrode components and order of assembly.
Take extreme care when handling electrode components. Use gloves when handling.
Prior to re-assembly, clean all parts with a NON-PETROLEUM based solvent.
Note: A cold boiler must be filled slowly and with return water from the mains no hotter
than 140 Deg F. This is to ensure that the porcelain insulators and glass tubes are not
heated too quickly. If the boiler is still hot, the feed water temperature should not be lower
than the boiler temperature. Also, the boiler should not be heated/cooled quicker than 3-
5 F per minute to protect the porcelain insulators from damage.
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Caution
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