Search Results for protective coatings and linings

Two-component polyurea elastomeric coating/lining systems are the newest technology in the protective coating/lining industry and a wide variety of applications have been developed. These include coating/lining applications over concrete, geotextile membranes, various metals for corrosion and decorative areas, and some plastics. This article discusses the formulation basics of polyurea technology and compares the technology to that of polyurethane and polyurethane/polyurea systems. It addresses performance issues and describes application processing considerations and safety practices of polyurea coating/lining systems.

This article discusses the concepts of quality control (QC) and quality assurance (QA), and clarifies the differences and similarities in the roles and responsibilities of QC and QA personnel. It describes the inspection procedures used to verify proper surface preparation and installation of the protective coating/lining system. Prior to beginning surface-preparation operations, many specifications will require a presurface-preparation inspection to verify the correction of fabrication defects and removal of surface contamination such as grease, oil, cutting compounds, lubricants, and chemical contaminants. When inspecting concrete prior to coating installation, three areas of concern exist: surface roughness, moisture content in concrete, and acidity/alkalinity of the surface. The article provides information on the industry standards for assessing surface cleanliness. It details postcoating application quality requirements, including measuring of dry-film thickness, assessing intercoat cleanliness, verifying minimum and maximum recoat intervals, performing holiday/pinhole detection, conducting cure/hardness testing, and assessing adhesion of the applied coating system.

This article provides a brief discussion on the common types of overlayers that can be used on a metal surface to protect it from corrosion. These overlayers include phosphate, chromate, and chromate-free conversion coatings; hot dip galvanizing; cementitious linings; glass and porcelain enamels; electroplating; thermal spray coatings; and rubber linings.

This article provides information on the municipal wastewater system components such as piping, pump stations, headworks, clarifiers, aeration structures, digesters, biosolids dewatering equipment, and sludge stabilization. It explains the major corrosion damage mechanisms to which those component parts of the system are exposed. It presents useful guidelines for selecting and using protective coatings in municipal sewerage collection systems and water reclamation facilities in wastewater treatment plants. The article includes annotated flow diagrams of a wastewater collection system, wastewater treatment plants, and spreadsheets listing the most widely used generic coating systems by structure and substrate material. It concludes with a section on quality watchouts when selecting or using protective coatings in municipal wastewater systems.

This article describes the paint systems generally used to protect steel structures, steel sheet, and bridges from corrosion, and how they deter corrosion. It provides a discussion on the basic design criteria of steel structures for corrosion protection. The article also explains the differences between prepaint and postpaint, and the steps involved in prepaint processing of steel. It presents the selection guideline for paint system evaluation. The advantages of corrosion protection are also discussed.

Inorganic chemical-setting ceramic linings are one of the most widely used construction materials in designing the protective linings for industrial installations. Monolithic linings can be applied by cast or gunite (shotcreting) methods over steel or concrete as well as brick and mortar masonry. This article provides a discussion on the function of monolithic linings, the advantages of these materials, the types of applications in which these materials can be successfully used, and the limitations of these linings. It describes the application procedures that should be followed to ensure proper installation of a dual-lining system. The industrial applications that illustrate the corrosion resistance and some uses of monolithic linings, as well as other applications in wastewater treatment systems and the chemical industry, are discussed.

The major benefit of the implementation of the corrosion-control technologies at Army installations is the extension of the service life of buildings and other structures. This article reviews the exposure of military facilities and equipment to a wide variety of environmental conditions, including soils, waters, or atmospheres of varying corrosivity. It presents the case studies illustrating typical examples of the types of corrosion problems found on military installations. The article describes the various corrosion-control technologies used in military facilities. These include protective coatings and linings, cathodic protection, advanced materials selection and design, water treatment, equipment inspection and monitoring, and below-grade moisture mitigation.

This article discusses the particular corrosion problems encountered and the corrosion control methods used in petroleum production (i.e., upstream) and the storage and transportation of oil and gas (i.e., midstream) up to the refinery (i.e., downstream). These control methods include proper material selection, protective coatings, cathodic protection systems, use of inhibitors, use of nonmetallic materials, and control of the environment. The article reviews the aspects of corrosion that tend to be unique to corrosion as encountered in applications involving oil and gas exploration and production. It discusses corrosion problems that are specific to the various types of environments or equipment used in secondary recovery, including producing wells, producing flow lines, and injection wells. Corrosion mitigation methods and guidelines are also discussed for each type of environment.

This article presents an overview of the different types of coating and lining materials available. It provides information on the various means of surface preparation and the equipment and techniques of coating application. The article discusses the coatings industry's response to the enacted as well as proposed legislation of limiting the use of potentially harmful or toxic raw materials or surface preparation and/or application techniques. The article summarizes the existing federal regulations affecting the coatings industry categorized according to the requirements of the Environmental Protection Agency and the Occupational Safety and Health Administration as well as the corresponding Code of Federal Regulation numbers.

This article provides an overview of the environmental performance of the most commonly used nonmetallic materials, including elastomers, plastics, thermosetting resins, resin-matrix composites, organic coatings, concrete, refractories, and ceramics. It also discusses the applications and uses of these materials.

This article provides a discussion on polyester coating applications such as powder coatings, can coatings, and automotive paints. It includes an overview, structure, properties, and benefits of vinyl ester resins. The article discusses the additives for both unsaturated polyester and vinyl ester coatings, namely, curing systems, thixotropic agents and fillers. It exemplifies polyester and vinyl ester coating, lining and flooring systems that are used for top-to-bottom protection of industrial plants and equipment. The article also highlights the concerns to be addressed when using polyesters and vinyl esters.

Surface coatings are essential in all facilities that process nuclear materials or use nuclear fission for power generation. This article describes the coatings used in two basic types of Generation 3 nuclear reactor designs in the United States and their containment size. These reactors are the boiling water reactor (BWR) and pressurized water reactor (PWR). The article provides information on the loss-of-coolant accident (LOCA) identified as the design basis accident (DBA), which can rapidly de-water the core of an operating nuclear reactor. To avoid LOCA, both the BWR and the PWR include emergency core cooling systems. The article describes a DBA test and other coating performance parameters necessary for safety-related coating systems. It provides a detailed account of the selection criteria of coating types in a nuclear plant. The article concludes by highlighting protective coating strategies in Generation 3 Plants.

This article discusses the factors affecting corrosion behavior. It describes galvanic corrosion and its protection methods. The article also provides information on coatings and inhibitors, which are used in corrosion protection.

This article presents information regarding the use of protective coatings in municipal potable water systems, including raw water collection and transmission, water treatment plants, and treated water distribution. It provides useful guidance for the selection and use of protective coatings in these municipal water systems. The most commonplace corrosion-damage mechanisms are highlighted. The article describes the most common materials of construction found in municipal water systems, namely, cast iron, ductile iron, carbon steel, precast concrete cylinder pipe and reinforced concrete pipe, prestressed concrete tanks, and stainless steel. It provides information on the most common generic coating systems used for new steel tanks and water storage tanks. It concludes with a discussion of quality watch-outs when selecting or using protective coatings in municipal water systems.

This article provides a detailed discussion on the functions, applications, types, and selection criteria of exterior and interior rail coatings. It includes a discussion on the corrosivity, inspection/maintenance, and qualification of applicators/inspectors/facilities.

This article describes the mechanisms of differential corrosion cells corrosion, microbiologically influenced corrosion, and stray direct current corrosion. It discusses the most common causes and contributing factors for corrosion and stress-corrosion cracking, as well as prevention, mitigation, detection, and repair processes.

This article provides an overview of the electrochemical nature of corrosion and analyzes corrosion-related failures. It describes corrosion failure analysis and discusses corrective and preventive approaches to mitigate corrosion-related failures of metals. These include: change in the environment; change in the alloy or heat treatment; change in design; use of galvanic protection; use of inhibitors; use of nonmetallic coatings and liners; application of metallic coatings; use of surface treatments, thermal spray, or other surface modifications; corrosion monitoring; and preventive maintenance.

This article discusses the processes involved in continuous hotdip coating of steel sheets, namely, hot and cold line processing, surface preparation, and post treatment. It outlines the properties and microstructures of metals and their alloys used in this process. The coatings considered in this article include metal coatings, such as zinc coatings, and alloy coatings, such as zinc-iron, types 1 and 2 aluminum, Zn-5AI, Zn-55AI, and lead-tin coatings.

This article describes the basic principles, processing steps, and benefits of continuous hot dip coatings. It provides useful information on the principal types of coatings applied in the hot-dip process. The types of coatings include galvanized coatings, galvannealed coatings, 55Al-Zn coating, 95Zn-Al coating, and aluminized coatings.

This article describes the characteristics of zinc-rich coatings that can be subcategorized according to the type of binder material used. It discusses the formulations of zinc-rich coatings with organic binders. The three major groups of inorganic zinc-rich coatings categorized by the Society for Protective Coatings are also discussed. These include postcured water-based alkali metal silicates, self-cured water-based alkali metal silicates, and self-cured solvent-based alkyl silicates. The article concludes with information on comparisons of inorganic with organic zinc-rich coatings.