TWI Industrial Member Report Summary 51/1977
By R M Rivett and S A Westgate
Background
Work was carried out on three machines of differing mechanical characteristics and electrode life was found to be independent of this parameter. The effect of dual pressure was investigated on one machine and it was found that lives could be extended from an average of 1300 welds, the life ending as a result of solidification cracking, to more than 3000 by increasing the forge load from 3.1 to 7.8kN. In the latter case the lives ended due to electrode sticking. Electrode life increases with increased forge level but the timing of the forge initiation must be precisely controlled so that it occurs at the end of the last current cycle. The extension in life is lost if the initiation is delayed by 1 cycle.