Some Investigations Regarding Oxygen Cutting (Report 1)

Cutting Efficiency of Some Available Tips

Abstract

As an important criterion for evaluating the tip performance, the authors empolyed, in addition to the drag, the cutting efficiency of oxygen expressed as square millimeter of cut area per liter of oxygen. In cutting study, for the sake of reproducible results, the cut area was calculated as the product of cutting speed by maximum cut thickness. The maximum cut thickness was defined as the thickness, beyond which the cutting action can not progress toward the direction of bottom in a wedge-shaped specimen under the referring cutting conditions.
In this first report, the cutting efficiency of some available tips was investigated by using such specimens as mentioned above, and the important findings may be summarized as follows :
(1) With increasing tip distance the cutting efficiency is slightly decreased.
(2) By oxygen pressure the cutting efficiency is greatly influenced, and at some specific pressure, which is peculiar to the type of tip, the highest efficiency can be obtained.
(3) The amount of acetylene flow for preheating has no significant effect on the cutting efficiency.
(4) The relationship among the efficiency, tip size and cutting speed, at the most favorable tip distance and oxygen pressure, was clarified by the experimental formulas obtained by the authors.
(5) From these experimental formulas it was. also revealed that, in ordinary cutting, at the speed in excess of 1200 mm/min the cutting action can not progress toward the direction of cutting in the plate, and that divergent nozzle tips have 15% higher cutting efficiency in comparison with simple nozzle tips.