Following from our previous tech tip which addressed some of the key elements associated with NDT, this Tech Tip discusses some of the more commonly used NDT techniques. For External (Surface) Flaw Detection, the NDT process typically starts with Visual Inspection, which can be enhanced by Dye Penetrant. Crack like defects can be readily manifest […]

In this modern age of design and manufacture, an essential complementary corollary to fabrication is the assessment of the component or structure, to ensure that it is ‘fit for purpose’. It is one thing to design the engineering system, and quite another to ensure it is made to the specifications envisaged, and, critically, that it […]

In many failure investigations, interpretation of the features on the fracture surface (or surfaces) can be extremely useful in determining the mode of failure. One of the most interesting and revealing features is that of micro-void coalescence (MVC). Micro-void coalescence is a high energy fracture mechanism in metals, which is very common and readily interpreted. […]

Flow Accelerated Corrosion (FAC) refers to a wear mechanism which results in severe wall thinning (up to 3mm/year) and metal loss of carbon steel piping and vessels exposed to flowing water and wet steam. FAC is often occurs in power generation units, including both conventional plants as well as nuclear facilities worldwide, but also occurs […]

The joining of components or structures is an essential feature of engineering and the practice of bolting components is ubiquitous. Despite its widespread appeal and usage, however, bolting is not a trivial exercise, and disregard of the fundamentals or lack of awareness of the subtleties associated with bolting, has led to some catastrophic failures. This […]

Corrosion, at the most basic level, may be considered as the dissolution of a metal in the presence of an aqueous solution (such as water). When metal corrodes in an aqueous solution such as oxygenated water, the metal anode is oxidised to form metal ions (typically M+), releasing electrons in the process. The electrons are […]

Steel is a remarkable material in that its microstructural characteristics can be altered by heat treatment, and consequently its properties and performance. Heat treatment would typically include i) heating of the steel (to an alloy dependent temperature), ii) soaking at that temperature, iii) cooling of the metal at some pre-determined cooling rate, and then iv) […]

Even in normal times, conventional pressures in the economy and in industry can lead to fluctuating production demands, temporary downturns, or even unexpected shutdowns, but with the current COVID-19 pandemic and lock-down restrictions this pressure is now even greater. There may be a need for many companies to consider localised closure and hence temporary mothballing […]

Within the realm of steel alloys there is a vast range of alloys and properties, and indeed, as is well known, the carbon content plays a significant role. Together with other alloying elements the carbon content is crucial with regard to the capacity to heat treat the alloy, and the heat treatment condition in which […]

An essential part of summer in South Africa is the ubiquitous meeting point around a braai, to enjoy a steak, a good chop, a stuk wors, a piece of fish or even a skilpadjie or two. Other countries try to emulate this South African tradition, with the Australian ‘barbies’, gas barbecues in America, or related […]