Ingenuity Magazine Fall 2020

Pond Ingenuity Fall 2020 9 T oo frequently, industries underestimate the necessity of preventative quality control methods. Actually, what truly happens is that the value is convoluted because of a simple accounting practice: capital expenditure versus maintenance expenditure. A capital expenditure is accounted for differently than a maintenance expenditure, which may be regulation required, and budgeting may be less elastic on the capital side. Thorough inspections and rigorous examination may be compromised in the name of speed and productivity goals. While this approach may accelerate the speed to the initial in-service, neglecting quality standards can only result in temporary solutions that generate consequences down the line. As a consumer, imagine the inconvenience of purchasing a defective product, especially one due to poor workmanship. When spending thousands of dollars on a car, you trust that extensive quality checks were conducted during the assembly of your vehicle. Your transaction is built on the promise that you are receiving a car that is reliable, well-built, and void of glaring imperfections. Even though you are unable to physically see all the operating elements of the car, you trust that your system is performing exactly as specified. As extra assurance, you might be offered a warranty for a period of time. If an avoidable mistake were glossed over or disregarded entirely, your car’s functionality could be compromised, which might result in unnecessary service fees. Spending thousands of dollars on a car only to result in malfunction would be at minimum an undesirable outcome. Now imagine that value changing from thousands of dollars to millions. For many industrial pipeline operating companies, this type of financial loss is a reality. These oil and gas distributors spend millions of dollars purchasing pipes to deliver sources of energy across the world. The operating and maintenance cost, or worse, a potential catastrophic failure, could have lasting ramifications. In the same way that a car being manufactured must undergo numerous quality reviews, the pipelines that will power our cities must be inspected just as thoroughly. The purchaser, for the large part, must rely on the reputation of the company they are purchasing from. In this relationship, there is not an option for a warranty. But one option to reduce defects is vendor surveillance, or inspection, during the manufacturing process to catch defects before they are sent to the field or accepted in the field. Buried steel structures will eventually corrode if not provided corrosion control. The primary form of corrosion protection for buried steel structures is usually one or more protective coatings supplemented by conjunction with cathodic protection. The coating systems reduces the surface area of the pipe to be protected by the CP. For structures transporting materials under pressure, such as pipelines, the need to prevent corrosion failures is important to prevent loss of product. If the product being transported is hazardous, the need to prevent corrosion failure is even greater. As pipelines age, their coating systems deteriorate. Atmospheric corrosion is easily handled though monitoring and maintaining the protective coating system. For buried pipelines, the cost of access alone is a challenge to maintaining the coating system, so the corrosion control system is commonly supplemented by cathodic protection. The effectiveness of the coating and cathodic protection system can be measured using a method called Direct Current Voltage Gradient. The DCVG technique was developed to locate coating faults, quantify their severity, and measure the effectiveness of the cathodic protection used without having to disturb the pipeline. When talking about a pipeline, it is possible to have design service lives that are in excess of 25 years, and actual service lives that may exceed 60–75 years. Coatings are the first pillar of below-grade corrosion control since they reduce the surface area of the pipeline that may experience corrosion. The design criteria for below-grade pipelines is the assumption of less than 1% failure of the coating systems for a 30-year design life. If the coating fails sooner, either the pipeline is excavated and coating repairs are performed, or more cathodic protection must be installed if that solution is possible. Case study after case study can affirm that preventative inspection measures are more effective long-term than reactive corrections. If we apply this logic to construction practices, the need for preliminary coating inspection becomes clear. Locating coating defects during application prevents the financial impact incurred when the coatings fail prematurely (Figure 1). Figure 1

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