7. PROCEDURE
7.1 INSTALLATION OF TEMPORARY SACRIFICIAL ANODE
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Pre-packed magnesium anodes shall be shall be soaked in a non-metallic container of potable water for a minimum
of 12 - 24 hours prior to the installation.
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Before installation anode location shall be marked and it shall be confirmed that the area is free of any underground
metallic services cables etc.
Immediately after excavating the required depth the anodes shall be lowered and care must be taken to avoid any
damage to the cable.
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Anode open circuit potential shall be measured using portable reference electrode prior to the installation.
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Pre-packed magnesium anodes shall be installed horizontally at pipeline invert level and at a distance of atleast
500mm away from pipeline.
Backfill anode with native soil and gradually pour water during the backfilling to provide better compaction
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Check open circuit potential of the anode after buried in soil and pouring sufficient water.
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The red anode tail cable and black cable from the pipeline are terminated inside test station and shall be bonded.
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Care must be taken while installing and laying the anodes to avoid breaking or any damage.
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The anode tail cables shall be terminated in the test post. Two of each 10mm2 XLPE/PVC cable shall be connected
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surrounding the anode surface to ensure better contact between anode and electrolyte (Soil).
for structure-to-soil potential measurements and one 10mm2 XLPE/PVC shall be bonded with Anode.
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Check the anode open circuit potential w.r.t portable Cu/CuSO4 Reference cell.
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Record all the inspection results obtained in the consolidated approved inspection check sheet
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Filling surface area shall be kept free from water, materials and debris.
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The excavated soil shall be laid, spread and levelled by manually.
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The anode tail cables shall be terminated in the loon type test post. Two of each 10mm2 XLPE/PVC cable shall be
connected for structure-to-soil potential measurements and one 10mm2 XLPE/PVC shall be bonded with Anode.
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Check the anode open circuit potential w.r.t portable Cu/CuSO4 Reference cell.
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Record all the inspection results obtained in the consolidated approved inspection check sheet.
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Filling surface area shall be kept free from water, materials and debris.
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The excavated soil shall be laid, spread and levelled manually.
7.2 INSTALLATION OF PERMANENT CATHODIC PROTECTION SYSTEM
The permanent CP system for the protection of underground piping shall be done using externally distributed mixed metal
coated Titanium tubular anodes installed in a shallow bed. The installation details of the CP components are as follows:
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