Nace CP 1, Руководство по эксплуатации

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RP0176-2003
NACE International
15
set until permanent electrical power becomes
available. Plans should be made for either tem-
porary power and early energizing of impressed
current systems or a short-term galvanic anode
system. Otherwise, serious corrosion of structure
members, as well of as the underwater compon-
ents of the impressed current system, can occur.
5.9 Design Drawings and Specifications
5.9.1 Suitable drawings should be prepared to design-
nate the overall layout of the CP system and the loca-
tion of significant items of hardware, corrosion test and
monitoring stations, bond boxes, insulators, and neigh-
boring buried or submerged metallic structures.
5.9.2 Layout drawings should be prepared for each
impressed current CP installation, showing details and
location of its components with respect to the structure
to be protected.
5.9.3 The locations of galvanic anodes should be
shown on drawings or recorded in tabular form with
appropriate notes as to anode type, weight, shape, and
location.
5.9.4 Specifications should be prepared for all mater-
ials and installation practices to be incorporated in con-
struction, inspection, and operation of the CP system.
5.9.5 Suitable, as-built drawings should be prepared
during and at the completion of all installations. These
drawings should include any deviations from original
design.
5.9.6 Complete records should be maintained. Details
of CP installations are necessary for trouble-shooting
and future design (see Section 15).
5.10 Design of Companion Facilities
5.10.1 If the design of an offshore CP system incor-
porates the use of insulating flanges or unions, locating
each insulating device in vertical piping minimizes inter-
nal shorting caused by accumulation of salts, metallic
residue, or other conductive materials. Such insulating
devices should not be located below the water line (see
Paragraph 6.7.1).
5.10.2 The potential sparking hazard of insulating de-
vices should be recognized and considered in the de-
sign and location of such devices.
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Section 6: Installation of Cathodic Protection Systems
6.1 Introduction
6.1.1 This section recommends procedures for instal-
ling CP systems in accordance with design consider-
ations outlined in Section 5.
6.2 Construction Specifications
6.2.1 All construction work performed on CP systems
should be done in accordance with drawings and spec-
ifications. The construction specifications should be in
accordance with procedures outlined in Sections 3, 4,
and 5.
6.3 Construction Supervision
6.3.1 All construction work performed on CP systems
should be done under the supervision of qualified per-
sonnel to verify that the installation is made in strict
accordance with the drawings and specifications. Ex-
ceptions should be made only with the consent of the
supervising corrosion specialist.
6.3.2 All changes from construction specifications
should be noted on as-built drawings.
6.4 Galvanic Anodes
6.4.1 Inspection and handling
6.4.1.1 Specific guidelines can be found in NACE
Standard RP0387.
11
6.4.1.2 Anodes should be inspected to ensure
that dimensions and weight conform to design
specifications and that any damage from handling
does not affect application.
6.4.1.3 In the case of weld-on anodes, the steel
cores should be inspected for conformance to
specifications. If the anode cores have welded
joints or connections, these should be inspected to
ensure compliance with structure welding specifi-
cations.
6.4.1.4 When galvanic anode suspension cables
are used for the lead wire, the cables should be in-
spected for strength, voltage drop, and good elec-
trical contact with the anode. When separate sus-
pension cables are used, care should be taken to
ensure that anode lead wires are not in such ten-
sion as to damage the lead wires or connections.
6.4.1.5 If coatings are specified for anode sup-
ports or suspension cables, they should be visually
inspected and repaired if damaged.
6.4.2 Installing anodes