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 […]

South Africa’s position in the world nuclear energy picture

  From the ICMEESA archive With its uranium enrichment expertise and technology, South Africa is in a strategic position to enrich and market its uranium and, perhaps in future, to provide fuel elements for manifold identical stages. Only thirty years have passed since Enrico Fermi gave a practical demonstration of a controlled fission chain reaction […]

Three steps for reducing total cost of ownership in pumping systems

  Electrical energy cost represents some 40% of the total cost of ownership of pumping systems, yet many organisations fail to introduce the proper steps to leverage cost reduction through efficiency improvements. The following major barriers must be recognised and addressed to solve this dilemma: Lack of proper metrics: Energy efficiency has traditionally not been […]

Water treatment: boilers, cooling and effluent

  From the ICMEESA archive Effluent treatment is based on the ingenuity of chemists and engineers. The chemist may devise a short-cut method for the precipitation of the components but the electrical engineer designs the controls while the mechanical engineer design filters, conveyers, agitators and others. The methods employed in effluent treatment can often be […]

Designing an augmented reality platform in an enabled environment

  Developing an augmented reality platform for use as a differential drive mobility aid in an enabled environment to help conduct simulations with various wheelchair constructs and to produce pitch and roll actuated actions. Physical or cognitive impairment may compromise the ability to walk. The degree of mobility largely determines the extent to which the […]

Some developments in winder brake control

  From the ICMEESA archive Methods of control for low and high pressure hydraulic braking systems which have been applied successfully to a number of hoists in South Africa. This article describes new and simplified control systems for low pressure and high pressure hydraulic braking systems with emphasis on air brake and low pressure oil […]