OXYGEN CUTTING

摘要

1509786 Burners ZENTRALINSTITUT FUR SCHWEISSTECHNIK DER DEUTSCHEN DEMOKRATISCHEN REPUBLIK 10 July 1975 [31 July 1974] 29003/75 Heading F4T [Also in Division B3] A method of oxygen cutting comprises using a flow of oxygen sufficient to at least partially destroy the gaseous contamination and oxide surface layers formed during cutting in a torch having a conically flared nozzle of circular crosssection, the operating parameters of which are given by the equations: d # = 0À40 Î (s/p) Œ 0À05 and d = (0À021 Î p + 1À54d # Œ 0À05, where d K is the diameter of the minimum nozzle bore in mms; d is the diameter of the nozzle mouth in mms.; p is the pressure of the cutting oxygen in kp./cm.2; and s is the depth of the cut in mms., the cutting speed (i.e. the speed of advance of the cutting nozzle parallel to the workpiece) being set so that the drag (i.e. the ratio of cutting speed to mean jet velocity) is in the range 1 to 8%, the length of a flame associated with the nozzle being at least five times the depth of the cut but at least 250 mm, the presence of the oxygen being between 16 and 60 kp./cm.2 and the depth of the cut being between 3 and 80 mm. The preferred cone angle is between 5 and 15 degrees, preferably 8 degrees. Examples of nozzle dimensions for different depths of cut are given.