Resistance welding applications in electrical engineering, precision mechanics

The growing use of heavy-duty electronic devices and components in motor vehicles has led to increased use of previously unused or only rarely used bonding methods. While soft soldering and crimping were the most frequently used methods until just a few years ago, these methods are today reaching the limits of their possibilities due to […]

Rehabilitation for failing water piping

New to South Africa is a system which rehabilitates the inner infrastructure of deteriorated or failing water piping using an array of cured-in-place epoxy pipe lining solutions. SABMiller’s brewery in Okahandja, Namibia, had a drainpipe failure. The network of pipes affected run beneath epoxy coated 30 MPA concrete floors supporting the plant’s heavy machinery and […]

Case study: remote condition monitoring of London Underground track circuits

Delivering a reliable remote condition monitoring system for the London Underground to enable maintainers to respond to failures before they occur. London Underground serves 1,7-billion passengers per year and the Victoria Line accounts for 213-million of those journeys. The line carries 89,1-million passengers per year in the peak service, offering the most intensive service on […]

Fundamentals of laser welding

  There are two of types of neodymium-doped yttrium aluminium garnet (Nd:YAG) laser welder, continuous wave and pulsed. As the name suggests, continuous wave or CW is either on or off, whereas pulsed lasers create welds by individual pulses. The pulsed laser uses high peak power to create the weld, whereas the CW laser uses […]

Designing high-pressure, high-volume pumps for harsh environments

  Pump designs fall mainly into two categories, centrifugal and reciprocating (piston) type, each with its own benefits and constraints. This article explores the design criteria and some of the applications. Information on the application and the fluids involved is key to matching the correct pump design to the application (see Fig. 1). Approaching a […]

Powder coatings based on epoxies and other synthetic resins

  From the ICMEESA archive Powder coatings as a means of finishing metallic objects have gained great popularity in the last five years. Many synthetic resins have been adapted to powders and at least a dozen different systems are currently in vogue overseas. While thermoplastic resins such as vinyl and polythene have been in use […]

Ilanga II: Under the hood of a sun chaser

  The engineering challenge of designing and building a solar-powered racing car for a strenuous eight-day international endurance race brings together research, theory and development while promoting alternative energy and technological innovation. The Ilanga II is a prototype solar racing car developed by the University of Johannesburg (UJ) Solar Team to compete in this year’s […]