Case Histories

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.

Recent Fiberglass-Reinforced Plastic Applications: Radome and Hybrid Bridge System

This article describes two case histories: construction and installation of a fiberglass-reinforced plastic (FRP) radome and the design, construction, and utilization of composite FRP/concrete bridge beams. The shape, structural requirements, and radar transmission requirements of the radome are discussed, as are the design, fabrication, and testing of the composite beams.

Interference Problems and Nonuniform Potentials in Cathodic Protection of a Complex Installation

After being in operation for some time, cathodic protection (CP) systems at compressor stations, refineries, and other industrial plants can experience problems. For example, the CP potential distribution can change for various reasons, because of isolating flange failures, alterations in pipeline systems, grounding systems, or reinforced concrete foundations. Some areas become underprotected and others overprotected. The extent of CP current required may exceed the capacity of rectifiers, and may also increase interference on foreign pipelines. This article describes the results of corrective measures for these problems.

Designing Cathodic Protection for Power Plant Applications

Designing cathodic protection (CP) systems for buried piping in power plants and other similar industrial facilities offers several unique challenges. This article discusses these challenges and provides case histories to illustrate the impact they have on CP system design and operation.

Stress Corrosion Cracking of Various Alloys—Part 2

Stress corrosion cracking (SCC) can lead to rapid and catastrophic failure. Failures often occur with little or no prior warning. A systematic approach is needed to evaluate any failure and identify its cause. This article continues the case histories begun in Part 1 and illustrate common features evident in SCC.

Tuberculation Corrosion in Industrial Effluents

Tuberculation in waste water has long been a concern. Causes are an adverse mixture of water chemistry, construction materials, microbiological attack, and flow rate. Low velocity permits particulates and corrosion products to form deposits. Accumulated deposition leads to partial or complete blockage of pipelines, trapping of pigs, under deposit corrosion, and tuberculation. Tuberculation reduces flow rate. This article discusses tuberculation and presents a case study.

Stress Corrosion Cracking of Various Alloys—Part 1

Stress corrosion cracking (SCC) can lead to rapid and catastrophic failure in many different metals and alloys. Failures often occur with little or no prior warning. A systematic approach is needed to evaluate any failure and identify its cause. The case histories in this article illustrate features that are commonly evident in various materials that experience SCC.

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.

Lining Prevents Biogenic Sulfide Corrosion In Wastewater Systems

Faced with serious concrete deterioration from biogenic sulfide corrosion within collection systems, engineers and municipalities are extending the service life of wastewater conveyance structures with the use of 100% solids polyamine systems designed for hydrogen sulfide (H2S) permeation resistance. This article explains how sewer interceptors, manholes, and lift stations were protected using fluid-applied linings.

Performance of Concrete Bars on Industrial Platform Substations

An electric company tested concrete construction members from substations in chemically aggressive environments to determine their load-carrying capacity after ~35 years of operation. This article describes the manner in which tests were performed and summarizes the results.

Advanced Coatings for Water Treatment Plant Components

Components of water treatment plants (WTPs) are susceptible to corrosion from constant immersion in water and proximity to chlorine. A case history of corrosion problems and their treatment at an Army WTP is presented. Solutions included using high micro-silica restoration mortar and advanced coal tar epoxy coatings.

Enhancing Asset Value Through Corrosion Management

The relative value of an aging asset depends on many parameters, among which are production rate/ continuity and integrity management (IM) costs. Reducing unplanned shutdowns and IM costs can maintain or even improve the relative asset value. This article describes—using data collected over a five-year period—how having asset corrosion management and risk-based inspection systems in place may achieve the above.

Amine Blush in Epoxy Coatings

Carbonated amine material, often called amine blush, is the reaction product of the amine functional curatives in epoxy paint with carbon dioxide (CO2) and water vapor. This article explains the formation of amine blush and discusses factors controlled by the applicator and those controlled by the paint manufacturer.

Developing Welding Procedures for Sour Service

Controlling the hardness of the weld heat-affected zone (HAZ) in sour service is essential to help prevent sulfide stress cracking. It is important to evaluate HAZ properties when developing welding procedures. The behavior of specific alloys during welding presents roadblocks to HAZ hardness control. Two cases are presented to show that weld thermal simulation is an efficient tool for developing welding procedures for sour service.

Investigating Polyethylene-Encased Ductile Iron Pipelines

This article presents several case histories where ductile iron (DI) pipeline sections have been investigated to ascertain the corrosion control benefits of polyethylene (PE) encasement. The procedures and results of the investigations are evaluated and discussed. These investigations demonstrate the overall effectiveness of PE encasement as a corrosion control system for DI pipe.