Cold Link Africa May/Jun 2017 | Page 17

EVENTS AND EXHIBITIONS INCORPORATING COLD CHAIN merSETA and chair of the organisers of previous WSSA competitions, was present and given recognition for the role he has played in WSSA. The four competitors in the trade of refrigeration and air conditioning were tasked with a practical project of making a model ice rink. The project had three modules to test the many different skills needed in the industry. The first module required the competitor to fabricate a copper tubing circuit for the secondary refrigerant circuit that would form the ice rink surface. The coil was to be constructed of 12 lengths of ½ inch of copper tubing, fed by a 7 / 8 inch copper header. Module one was to test the skill of measurement, reading of a drawing, brazing and fabrication. In the second module, the copper coil was connected to a refrigeration system having a R134a hermetic condensing unit, low pressure separator, brazed plate heat exchanger (R134a to propylene glycol) and an open buffer tank with submersible pump for the propylene glycol. All components, including level switches, had to be connected to a prewired electrical panel. The system had to be leak tested, evacuated, charged and commissioned to have a frozen ice rink. The final module tested the skill of fault finding and the repair of faults set by judges during the competitor’s absence. The original time allowed for the three modules was 18 hours over the three-day period and was extended to 30 hours to allow for some of the short comings of the competitors and availability of components. All competitors finished with some assistance given to David le Grange (Airvent, Brackenfell, Cape Town). Tyrone Bunce (Standard Refrigeration, Durban) with the top score, received The workstations for the four competitors in refrigeration and air conditioning arrived by truck from Johannesburg. the gold medal. The bronze went to Valentin Valente and the silver to Lionald Wooldridge, both of OTTC in Springs. The three judges, Peter Hoetmer (Metraclark, Johannesburg), ‘Boenie’ Louw (Tshwane South College) and Kobus Harmse (Cape Town College) were close in their markings with the final adjudication by the national skills expert, Bob Vuletic (Multistage Cooling, Johannesburg), who commented, “The standard of t