Nace CP 1, Руководство по эксплуатации

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RP0176-2003
16
NACE International
6.4.2.1 Anodes should be installed according to
construction specifications.
6.4.2.2 When anodes are welded directly to the
structure, the welds should be inspected for con-
formance to the structure construction welding
specifications.
6.4.2.3 Use of doubler and/or gusset plates
should be considered for anodes mounted on
standoff pipe cores and weighing more than 230
kg (500 lb).
6.4.2.4 Doubler and/or gusset plates may be in-
stalled on anode supports at the time of anode in-
stallation. If installed as part of the anode fabrica-
tion, these plates may be subject to serious dam-
age during anode hauling and handling.
6.4.2.5 Suspended galvanic anodes should be in-
stalled after the structure is set on location off-
shore, and the anode cables should be tested for
good electrical contact to the structure after instal-
lation.
6.5 Impressed Current Systems
6.5.1 Inspection and handling
6.5.1.1 The rectifier or other power source should
be inspected to ensure that internal connections
are mechanically secure and that no damage has
occurred during shipping and handling. Name-
plate and actual rating of the direct current power
source should comply with construction specific-
ations.
6.5.1.2 Impressed current anodes should be in-
spected for conformance to specifications for
anode material and size and length of lead wire
and to ensure that the anode cap (if specified) is
secure. Lead wires should be carefully inspected
to detect possible insulation defects. Defects in
the lead wires and/or anode caps must be properly
repaired or the anode must be rejected.
6.5.1.3 Care should be exercised in handling all
impressed current system components prior to fin-
al installation.
6.5.2 Installation provisions
6.5.2.1 A rectifier or other power source should be
installed out of the way of operational traffic and
remote from areas of extreme heat or likely con-
tamination by mud, dust, water spray, etc. In
areas in which two or more rectifiers are installed,
the rectifiers should be spaced for proper flow of
cooling air.
6.5.2.2 Wiring to rectifiers shall comply with any
applicable regulatory codes and with the oper-
ator’s specifications. An external disconnect switch
in the AC wiring to the rectifier should be provided.
The rectifier case shall be properly grounded.
Connecting the negative to the case prevents in-
advertent reversal of polarity.
6.5.2.3 On thermoelectric generators, a reverse
current device should be installed to prevent gal-
vanic action between the anode and structure if
the flame is extinguished.
6.5.2.4 Impressed current anodes should be in-
stalled in accordance with construction specific-
ations. Special care should be taken to avoid
damage to anodes and their lead wires during in-
stallation. Careful supervision of this phase is
most essential to proper long-term performance of
the CP system.
6.5.2.5 Conductor cable connections to the recti-
fier from the anode(s) and the structure must be
mechanically secure and electrically conductive.
Before the power source is energized, verification
should be made that the negative (-) conductor is
connected to the structure to be protected, that the
positive (+) conductor is connected to the
anode(s), and that the system is free of short cir-
cuits.
6.5.2.6 Connection between the positive header
cable and lead wire(s) from the anode(s) should
be mechanically secure and electrically conduc-
tive. The connections must be sealed to prevent
moisture penetration and ensure electrical isola-
tion from the environment. Submerged connec-
tions require seals suitable for the water pressures
and environment to which they may be subjected.
6.5.2.7 When installing a suspended anode for
which separate suspension is required, care
should be taken that the lead wire is not in such
tension as to damage the anode lead wire or con-
nections.
6.5.2.8 Operating personnel should be trained in
the function and need for such a system to ensure
continued energization of the system.
6.6 Corrosion Control Test Stations, Connection, and
Bonds
6.6.1 Installation provision
6.6.1.1 Test leads to pipelines associated with off-
shore structures must be mechanically secure and
electrically conductive and should be readily ac-
cessible.
6.6.1.2 Both the pipe and the test lead wires
should be clean, dry, and free of foreign material
at points of connection when the connections are