The greatest use of high-temperature water and steam is in electrical power generation.
Most pipeline cathodic protection applications involve either galvanic anode or impressed current systems installed in earth for protection of external surfaces.
Coating operations of almost any size must include some type of meaningful test program.
The main causes of corrosion of steel in concrete are chloride attack and carbonation. These two mechanisms are unusual in that they do not attack the integrity of the concrete. Instead, aggressive chemical species pass through the pores in the concrete and attack the steel. This is unlike normal deterioration processes resulting from chemical attack on concrete.
Although atmospheres can be classified into four basic types, most of them are mixed and present no clear lines of demarcation. Furthermore, the type of atmosphere may vary with the wind pattern, particularly where corrosive pollutants are concerned.
Two of the most fundamental and informative field measurements are soil resistivity surveys and pipe-to-soil potential surveys.
In water, the concentrations of various substances in dissolved, colloidal, or suspended form are typically low, but may vary considerably depending on the components and usage. For example, hardness values of up to 400 parts per million of calcium carbonate is sometimes tolerated in public supplies of potable water, whereas 1 ppm of dissolved iron would be unacceptable.
Steel structures such as bulkheads, piles, offshore drilling platforms, etc., may be protected with either sacrificial galvanic anode or impressed current cathodic protection systems.
Several elements of preplanning are necessary to effectively execute the condition survey. The first is a logical breakdown of the facility, and the second is to have a grading system to evaluate the observed conditions.
Corrosion failures are often subtle and a result of invisible localized effects in the form of pits, intergranular corrosion, or attack within crevices.
Any corrosion management implementation process should comprise three phases: pre-implementation, implementation, and post-implementation. Any shortcomings will adversely affect the outcome, effectiveness, and quality of the process. This article discusses corrosion management implementation issues and shortcomings that were observed during various campaigns or audits from around the world.
In every industrial environment, the safety factor is an important consideration. In some environments, including the application of protective coatings, it is of overriding importance. This article explores many of the safety factors that need to be considered.
It is important to maintain inhibitor concentrations at a safe level in waters containing dissolved salts, particularly if these include chlorides.
Although the primary focus of a corrosion engineer is on the chemical stability and corrosion resistance of these materials, it is critical to cooperate with other design team members familiar with the mechanical, physical, and other properties to ensure that the desired materials performance can be achieved.
Experience has shown that even when impossible circumstances appear to be present, substantial cost savings are possible by intelligent use of corrosion data and good design practices.