Search Results for periodic system

This article presents a diagramatic representation of a periodic system that illustrates the fundamental alloying nature of iron for ferrous metallurgists.

Reliability is a measure of the capacity of equipment or systems to operate without failure in the service environment. This article focuses on reliability in design and presents equations governing the instantaneous failure rate, general reliability function, mean time to failure, mean time between failures, and useful life period. The article describes the calculation of reliabilities for series and parallel arrangements of a complex system. It provides a comparison of probabilistic and deterministic design and concludes with a discussion on reliability growth.

This article provides basic information on the chemical elements and their arrangement into a periodic table based on recurring similarities in the fundamental nature of the elements. These elements follow a periodic pattern related to the electron configuration that allows them to be arranged into the convenient periodic table.

This article provides basic information on chemical elements and their arrangement into a periodic table based on recurring similarities in the fundamental nature of the elements.

This article explains how an engineer might go about assessing the risk of microbiologically influenced corrosion (MIC) in an industrial situation. It describes the systems that are susceptible to the effects of MIC by sulfate-reducing bacteria (SRB). The article discusses the effects of microorganisms other than SRB on metals. SRB-related problems, which are the most common MIC issue, are also explored. The article describes the test procedures used to enumerate microbiological populations. It concludes with a discussion on risk assessment based on operating conditions.

This article provides an overview of the components of a resistance welding machine. It focuses on the single-phase control system and medium-frequency direct current system of resistance welding. The article also includes information on their feedback systems, rectification systems, and power sources.

This article focuses on the aspects associated with inspection related to pressure vessels and pipework. These aspects include inspection policy, inspection planning and procedures, inspection strategy, inspection methodology, preparation for inspection, invasive inspection, internal visual inspection, and non-invasive inspection. Inspection execution, risk-based inspection, competence assurance of inspection personnel, inspection coverage, inspection periodicity, inspection anomaly criteria, assessment of fitness, and reporting requirements, are also discussed. The article addresses the data acquisition, reporting and trending, and review and audit for the inspection. It reviews inspection techniques, including visual inspection, ultrasonic inspection, and radiographic inspection.

Chemical elements are the basic chemical substances; that is, they cannot be decomposed by chemical change or made by chemical union. These elements follow a periodic pattern related to the atomic mass of each that allows them to be arranged into a convenient table. This article includes a series of tables: the first gives the names and symbols of the elements in alphabetical order and the second lists the elements in order by atomic number and give the atomic weight for each. The periodic table of the elements also is included in the article.

Resistance welding (RW) encompasses many variations on the basic theme of local Joule heating while an external pressure is applied. This article provides an overview of the most generally applied RW processes, followed by a discussion on the general design aspects of various resistance-welded joints. The various resistance-welded joints include spot welds, projection welds, seam welds, and butt welds. The article explains the relative contributions of the Joule, Peltier, and Thomson effects for typical RW scenarios. It concludes with information on the electrode “follow” behavior.

Pulsed-current plating can be defined simply as metal deposition by pulsed electrolysis, which involves using interrupted direct current to electroplate parts. This article discusses the advantages and limitations of pulsed-current plating and provides information on the process principles and control, solution composition, operating conditions, and necessary equipment modifications.

Dew-point corrosion occurs when gas is cooled below the saturation temperature pertinent to the concentration of condensable species contained by a gas. This article discusses dew-point corrosion problems in the susceptible areas of dry flue gas handling systems. The corrosion problems associated with the nitrate stress-corrosion cracking in heat-recovery steam generators are also discussed. The article presents general comments on the materials selection; plant operation; use of neutralizing additives; and maintenance, good housekeeping, and lagging (insulation). It concludes with information on guidance for maintaining specific sections of the plant.

This article discusses the effects of parameters on corrosivity and explains why it is critical to examine the parameter interactions prior to capturing the synergistic effects of the parameters on corrosion. It examines the methods of internal corrosion prediction for multiphase pipelines. The article reviews methodologies to perform internal corrosion direct assessment for pipelines. Real-time monitoring techniques for assessing actual corrosion at critical locations are discussed. The article also presents the case studies for multi-technique electrochemical corrosion monitoring.