Case Histories

Deep Anode Bed in a Flowing Artesian Aquifer

In April 2013, the Las Vegas Valley Water District attempted to install a 500-ft (152-m) deep anode bed for an impressed current cathodic protection system. Before the anodes could be installed, ground water began flowing out of the top of the hole at ~50 gal/min (189 L/m).

NACE International’s Annual Corrosion Career Survey Results for 2015

Corrosion professionals in North America and Europe have experienced another year of continued growth in career opportunities and salary levels, according to the 2015 Corrosion Career Survey conducted by Materials Performance magazine.

Belzona Case Study on Pipeline Protection

An international oil and gas exploration and production company was looking to enhance oil recovery techniques in Oman. Internal coating of the pipelines provided corrosion protection, reduced friction, and improved flow efficiency when conveying corrosive water slurry, and offered adequate corrosion protection during subsequent transportation of recovered crude oil.

Wanted: Technical Articles for MP

To successfully communicate the wide variety of corrosion-related issues affecting corrosion professionals today, MP is actively encouraging corrosion control professionals worldwide to submit technical articles to share their corrosion-related experiences with over 36,000 NACE International members around the globe.

Cathodic Protection for Water Mains in a High-Consequence Transit Corridor

To protect pipelines in a transit corridor where they crossed underneath the light-rail tracks, construction of the line included retrofitting the pipelines with a precast concrete box culvert casing and installing an impressed current cathodic protection (ICCP) system.

Wireless Remote Monitoring of Cathodic Protection Systems

Wireless monitoring technologies provide the ability to acquire impressed current cathodic protection (ICCP) system performance data from remote locations using modem-equipped personal computers. The technology can monitor the remote ICCP system’s amperage, “instant-on” and “instant-off” potentials in a central location, and provide personnel with immediate warnings of system problems. Case studies are presented for one Air Force and three Army installations, each with a different approach for the monitoring.

Pipeline Restoration at a Generating Station Using Chemical Grout

A gravity-flow water inlet line had developed many ruptures and cracks, leading to appreciable groundwater inflow. Contaminants brought in by the groundwater increased the cost of treating the water for station use. The problem was solved by injecting chemical grout to the exterior side of the pipe.

Effective Rehabilitation Planning for a Natural Gas Transmission Line—Part 1

This article describes the pipeline rehabilitation program developed by the natural gas transmission company in Colombia, South America. Part 1 presents the work accomplished to develop the Effective Rehabilitation Plan (ERP). Part 2 discusses the ERP in detail, including results and accomplishments.

MMO-Coated Titanium Anodes for Cathodic Protection—Part 2

Mixed metal oxide (MMO) anodes find extensive use in impressed current cathodic protection installations. Part 1 of this article covered the electrochemistry, manufacture, and operation of these anodes. Part 2 presents three case histories showing application of MMO anodes.

Real-Time Monitoring Affects Cathodic Protection

The need for real-time data is affecting the ability to provide cathodic protection (CP) to pipelines. The connection of electronic equipment required for remote pressure monitoring, metering information, valve operators, and other functions creates a direct short from the CP on the pipeline to the electric power company alternating current grounding system. In essence, the CP system now must protect not only the pipeline, but also a sizeable bare copper grounding grid. This problem creates pipe-to-soil potentials that may not meet the desired criterion. This article covers the use of decoupling devices to remedy this problem.

Copper Pipe Failure by Microbiologically Influenced Corrosion

After a detailed investigation on the failure of copper water service pipes in a water distribution system, microbiologically influenced corrosion (MIC) was found to be the cause. Increased system disinfection appears to have remedied the problem. MIC is often overlooked in corrosion investigations of drinking water systems. This case history is a good example of telltale signs of MIC and the water environments in which this can occur.

Corrosion Control Technologies for Wastewater Treatment Plants

Wastewater treatment plant components generally experience both atmospheric and immersion corrosion. Hydrogen sulfide (H2S), which is usually present, has wide-ranging effects in wastewater systems, most notably causing corrosion and odor problems. The corrosion problems can be mitigated by a combination of strategies including judicious selection and implementation of emerging corrosion-resistant coatings.

Cathodic Protection of Pipe Encapsulated in Polyethylene Film

Case histories are presented where polyethylene encasement and cathodic protection have been used together to effectively control external corrosion of ductile iron pipelines in corrosive soils. The four case histories evaluated include impressed current and galvanic anode protection.

Prevention of Micro-Flow Marks in Cathodic Electrodeposited Primer Coating in Automotive Industries

There was a defect of severe micro-flow mark lines in cathodic electrodeposited (CED) primer coating on car components. This problem was highlighted after final painting. This article describes the tests performed to determine the root cause of the defect. Tests included a surface profile of the CED coating and the determination of the microstructure and nickel content of the phosphate coating beneath the CED coating. The investigation identified the optimum concentration of nickel in the coating to refine phosphate grain size and create a unity crystal aspect ratio. It also found that the triple point junction of phosphate crystals determines the porosity to provide a uniform CED coating surface finish.

Centrifugally Cast Fiberglass-Reinforced Polymer Mortar Pipe for a Large-Diameter Interceptor Sewer

This article discusses one city’s approach to preserving the integrity of its infrastructure through the use of corrosion-resistant piping systems. Technological developments in centrifugally cast fiberglass pipes have provided installation advantages and lifelong benefits to municipalities.