Cathodic Protection Design, Installation, Commissioning & Monitoring

Cathodic protection systems, whether impressed current or sacrificial anode system, are a cost-effective means of preserving and controlling the corrosion of underground metallic structures. A single cathodic protection system can work to protect many kilometers of pipe and work to stop bursts and leaks which can be very hazardous, costly and disruptive. Cathodic protection systems also greatly extend the asset life span of the pipelines they are designed for, meaning renewals can be put off by decades.

Select Solutions’ engineers and technicians have extensive experience in the design, installation, commissioning and maintenance in both sacrificial anode and impressed current cathodic protection systems. Personnel at Select Solutions specialise in the cathodic protection of pipelines and have been involved in the end to end process of design, installation and commissioning systems for gas pipelines, water pipelines, water tanks, and electrical tower footings. We have also provided expertise in monitoring and maintaining marine systems.

A single cathodic protection system for a pipeline can be anything from a sacrificial anode system that is very easy to install, design and monitor that will protect up to 100km of new pipeline, or a more complex impressed current system that requires a power supply, is more difficult to design and install and needs bi-monthly monitoring which will commonly protect 2-5km, something more or less, for older pipelines laid before 1980.

All systems designed, installed and commissioned by Select Solutions are in line with AS2832:2015.

Protection Level Monitoring/ Potential Surveys

Potential surveys give an indication of whether a structure is actively corroding or not, how fast corrosion is occurring and what the nature of the corrosion is. Potential surveys record the voltage difference between the soil and the structure being tested over about a 20 hour period at corrosion test points that are installed on the structure, for pipelines, generally 500m apart. These recordings are then compiled into a report to give an overall view of how corrosion is acting on the pipeline. Potential Surveys are carried out in accordance with AS 2832.1 – 2015 “Cathodic Protection of Metals – Part 1: Pipes and Cables” as well as AS 2885.1 – 2012 “Pipelines – Gas and Liquid Petroleum – Part 1: Design and Construction”.

Select Solutions has over 150 data loggers currently in service, which are calibrated annually and our vehicles are especially equipped for the configuration and download of data loggers in the field. This group uses the latest software systems for analysis and reporting of data including assessment to AS 2885 and AS 2832 standards.

Corrosion Test Point Installation

Corrosion test points are the staple of monitoring protection and most corrosion investigations on structures, whether they be single buried structures like LPG gas tanks or structures that span over many kilometers like metallic pipelines. A corrosion test point is simply an electrical cable that is welded (usually using an exothermic cad weld) to the surface of the structure. This cable is then brought up to the surface of the ground and stored in a small, usually A4 size pit for technicians to access as they require.  These test points are required for protection level monitoring/ potential surveys, electrical/continuity fault finding, coating defect surveys and electrolysis/stray current testing to name a few.

Select Solutions’ technicians are training to install corrosion test points, safely and efficiently while being able to restore coatings on structures effectively too.

Electrical/Continuity Fault Surveys

Corrosion protection systems fail or demand an unnecessarily large current output when structures are in direct contact with unprotected underground services such as copper water services. Electrical shorts on cathodically protected pipelines can occur directly, when other metallic structures contact the pipeline, or indirectly when insulating joints or flanges fail or have not been installed correctly.

Select Solutions has procured the most effective equipment to find electrical faults on pipelines. Our personnel are trained and experienced to high standards so they possess a large degree of skill in conducting these electromagnetic coil surveys to identify and locate electrical and continuity faults affecting protection levels.

Coating Defect Surveys (DCVG and Pearson)

The successful application of cathodic protection and in general corrosion prevention on underground structures is directly linked to the extent and severity of coating defects. Pipeline coating defect surveys are performed to identify defects on existing pipelines and to check for damage that may occur during installation of newly laid pipelines.

Select Solutions has been conducting coating defect surveys on hundreds of kilometers of transmission pipelines for many years. This high level of survey activity has provided the Select Solutions team with extensive experience in coating defect surveys, using both the Direct Current Voltage Gradient (DCVG) in accordance with AS4827.1 – 2008 and “Pearson” methods. In the last ten years, corrosion group personnel have taken part in more than 3500 km of coating defect surveys on natural gas pipelines of varying coating quality over conditions ranging from dry and sandy to wet and swampy in suburban area to cross country pipelines that run between Australia’s states.

Coating defect surveys provide accurate location of defects and identification of high-risk areas of deteriorated coating where corrosion can occur, being able to detect even a pinhole defect in a coating. The surveys can also be used to detect coating and pipe damage caused by third party activity. The use of GPS equipment providing accurate and retraceable locations of coating defects is an additional option that this group can provide.

Electrolysis /Stray Current Testing Services

Stray current electrolysis corrosion occurs when DC current from the railway and tramway systems travels via nearby underground metallic structures, rather than through soil to complete its journey back to the railway system’s substations.

Select Solutions has a long history of knowledge and experience in the stray current field, currently representing two authorities on the Victoria Electrolysis Committee, which allows for special analysis of pipe to soil potential recordings that assess the effect of stray current on pipelines, and if necessary, recommend any mitigation measures required.

Electrical Surge Protection

Pipelines in the vicinity of high voltage power systems can be subjected to hazardous voltages due to earth potential rise (EPR) and low frequency induction (LFI). Select Solutions can provide expert design and maintenance services for pipeline earthing systems and surge protection equipment across insulating joints in accordance with AS/NZS 4853-2012 Electrical Hazards on Metallic Pipelines.

Contact Details

Alireza Kouklan
Corrosion Protection Manager

t: (03) 9396 7657
m: 0458 704 987
e: alireza.kouklan@select-solutions.com.au 

 

 

Candice Blackney
Corrosion Protection Engineer

t: (03) 9396 7654
m: 0427 703 574
e: candice.blackney@select-solutions.com.au