5.1 Further examination of electrical connections and discussion of results
A current rating of 600A is the normal supply output from most power welding machines. The Dynasty welding machine in the Tunnel at the University of Southern Queensland (TUSQ) has a maximum current output 0f 700A at 60% duty cycle. Going beyond the maximum current limit is practically beyond the capability of the available facility but for the purpose of analysis, current flow up to 2000A will be used. Fig.4.3 and Table 4.1 have shown that any tungsten diameter less than 8mm will not produce a very effective temperature distribution for a 50mm diameter heat shield of 2mm thickness. Here the 10mm diameter tungsten rod is properly examined and heat transfer limitations explained.