Cathodic Protection
Purpose
The purpose of this awareness session is to ensure that Cathodic protection activities are carried
out safely, efficiently, and in accordance with established best practices, as well as in full
compliance with Saudi Aramco’s applicable standards and Project specifications.
Definition
Cathodic Protection is a technique used to prevent corrosion of metal surfaces, particularly in
buried structures. It works by applying a direct current to the metal, which makes it the cathode of
an electrochemical cell, thus preventing oxidation and corrosion. This method is widely used in
various industries, including oil and gas, to protect pipelines, storage tanks, and offshore
platforms.
Galvanic Anode
A galvanic anode, or sacrificial anode, is the main component of a galvanic cathodic protection
system used to protect buried or submerged metal structures from corrosion.
Anode Installation
Anode Installation shall be carried out as per approved IFC Drawing
Piping installation and trench shall be ready for installation of anode prior to soaked the anode in
water
• Immersed the prepackaged anode in water for at least 24hrs before installation
• Anode to be installed horizontally, parallel to piping equipment at 1mtr distance
• As soon as the anode are laid out their cable tails shall be arranged centrally for vertical exit from
the bottom of the trench
• Both ends of each cable shall be firmly sealed with insulating tape and/or other sealing
materials to prevent dust & moisture.
• Sufficient length shall be provided for both ends of each cable in the measurement of cable
lengths.
• Sand filling, protection cover and backfilling work shall be conducted as early and promptly as
possible.
ANODE SOAKING IN WATER
Cable connection to structure
• Remove pipe coating from and area of approx. 100mmx100mm
• Clean the area with brush and filing
• Thermite weld the cable to structure
• Test strength of connection by lightly tapping top of weld with a one-pound hammer
• Remove all weld slag, sharp edges with metal File and wire brush
• Coating repair shall be applied after cleaning the thermite welded points.
• Anode shall be backfilled to depth of 300mm above anode
• On completion of partial backfilling the trench shall be further soaked with water to aid
compaction
Test Box Installation
• Test Box Station shall be installed flush mounted in top of finished grade level
Measurement of CP Potential
• Pipe to soil potential to be measured with reference to Cu/CuSO4 reference electrode for buried
structure
• Check test leads with multimeter of structure to electrolyte, to measure the voltage potential.
• Verify that the pipe to soil monthly potential survey for the installed CP of buried structures
• The pipe-to-soil potential value shall range between -1.0 V and -2.5 V, in accordance with SAES-X-
400, Table 4.
