3.2.2
Anode Installation
Unless otherwise authorized, installation shall not proceed without the
presence of the Contracting Officer. Anodes of the size specified shall be
installed to the depth indicated and at the locations shown. Locations may
be changed to clear obstructions with the approval of the Contracting
Officer. Anodes shall be installed in sufficient number and of the
required type, size, and spacing to obtain a uniform current distribution
over the surface of the structure. The anode system shall e designed for a
life of 25 years of continuous operation. Anodes shall be installed as
indicated in a dry condition after any plastic or waterproof protective
covering has been completely removed from the water permeable, permanent
container housing the anode metal. The anode connecting wire shall not be
used for lowering the anode into the hole. The annular space around the
anode shall be backfilled with fine earth in 150 mm 6 inch layers and each
layer shall be hand tamped. Care must be exercised not to strike the anode
or connecting wire with the tamper. Approximately 20 L 5 gallons of water
shall be applied to each filled hole after anode backfilling and tamping
has been completed to a point about 150 mm 6inches above the anode. After
the water has been absorbed by the earth, backfilling shall be completed to
the ground surface level.
3.2.2.1
Single Anodes
Single anodes, spaced as shown, shall be [connected] [connected through a
test station] to the pipeline, allowing adequate slack in the connecting
wire to compensate for movement during backfill operation.
3.2.2.2
Groups of Anodes
Groups of anodes, in quantity and location shown, shall be connected to an
anode header cable. The anode header cable shall make contact with the
structure to be protected only through a test station. Anode lead
connection to the anode header cable shall be made by an approved crimp
connector or exothermic weld and splice mold kit with appropriate potting
compound.
3.2.2.3
Welding Methods
Connections to [ferrous pipe] [metal tanks] shall be made by exothermic
weld methods manufactured for the type of [pipe] [tank] supplied. Electric
arc welded connections and other types of welded connections to ferrous
pipe and structures shall be approved before use.
3.2.3
Anode Placement - General
Packaged anodes shall be installed completely dry, and shall be lowered
into holes by rope sling or by grasping the cloth gather. The anode lead
wire shall not be used in lowering the anodes. The hole shall be
backfilled with fine soil in 150 mm 6inch layers and each layer shall be
hand-tamped around the anode. Care must be exercised not to strike the
anode or lead wire with the tamper. If immediate testing is to be
performed, water shall be added only after backfilling and tamping has been
completed to a point 150 mm 6 inches above the anode. Approximately 8 L 2
gallons of water may be poured into the hole. After the water has been
absorbed by the soil, backfilling and tamping may be completed to the top
of the hole. Anodes shall be installed as specified or shown. In the
event a rock strata is encountered prior to achieving specified
SECTION 13110A
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