Nace CP 1, Руководство по эксплуатации

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Installing C.P. Components 8:20
CP 1 – Cathodic Protection Tester Course Manual
©
NACE International, 2000
07/01/04
Handling and Inspection of Anodes and Cable
Impressed current anodes should be inspected for conformance to
specifications concerning correct anode material and size, length of lead
wire, and end cap, if used. Care should be exercised to avoid cracking or
damaging anodes during handling and installation.
Lead wire should be carefully inspected to detect defects in insulation. Care
should be taken to avoid damaging the insulation on the wire. Defects in the
lead wire must be repaired, or the anode must be rejected.
Anode backfill material should conform to specifications. The backfill used
around impressed current anodes is a carbonaceous material called coke
breeze. It serves two purposes. First, it enlarges the size of the anode, thus
reducing the anode-to-ground resistance. Second, it provides a uniform
environment around the anode; this greatly increases anode life since most
of the current flows electronically from the anode into the backfill, thus
reducing electrolytic action on the anode. What electrolytic flow does occur
causes relatively uniform corrosion of the anode rather than the localized
action that can occur if the anode is backfilled in soil.
Coke breeze backfill can be tamped around a bare anode or anodes may be
purchased prepackaged in backfill as shown in Figure 8.18.