Some Investigations Regarding Oxyagen Cutting (Report 3)

Effect of Oxygen Purity on the Cutting Efficicency

Abstract

Cutting test was carried out by using oxygen of various purities, i.e. 99.8 to 85 per cent. From the test results the relationships among oxygen purity, the maximum thickness that can be cut and cutting variables were obtained with a fair degree of accuracy. The main feature of the deleterious effects of lower purity oxygen is that for a cut of given thickness cutting speed must be lowered, and tip size enlarged. Consequently, the lower the purity of oxygen, the lower the cutting efficiency. The purity of commercially pure oxygen is 99.8 per cen. If this purity is raised to absolute 100 per cent, a considerable increase in cutting efficiency may be obtainable.
The water vapor contained in oxygen and the temperature of oxygen seem to affect more or less on the cutting action, but within the ranges normally encoutered their effects are negigible in extent.
In addition to the above test, ignition temperature of steel was surveyed. Judging from the results, it is probable that the ignition temperature is about 970°C in the range of oxygen purity from 100 to 65 per cent. However, if the purity is decreased from the above range, the ignition temperature rises conspicuously.