| 摘要 |
676,301. Blowpipe burners. VOLCAN SOC. ANON. May 27, 1949 [May 27, 1948], No. 14265/49. Class 75(i) In a process of oxygencutting of metals by means of an oxygen cutting apparatus provided with a set of nozzles each nozzle being adapted for cutting metal of specified thickness, the oxygen supply pressure is maintained at a constant value, greater than the critical pressure, and each nozzle is formed with an oxygen outlet conduit having a convergent portion with an apical angle of substantially 15 degrees, followed by a cylindrical restricted passage and by a divergent conduit portion having an apical angle of substantially 7 degrees. Oxygen is supplied at a predetermined constant pressure to an inlet conduit 10, Fig. 2, to pass through a conduit 11 having a cut off valve 12 to a head 13 carrying a nozzle 14. The latter has a central cutting oxygen passage having a cylindrical part 36, a convergent part 37 having an included angle of substantially 15 degrees, a cylindrical orifice 38, and a divergent outlet 39 of 7 degrees apical angle. In the head 13 the oxygen passage is formed with a wide angle bend 25 in order to minimize the pressure drop therein. Oxygen passes also from the conduit 10 through a control valve 16 to a passage 17 leading to a mixing chamber 18 supplied with acetylene from a conduit 19 through a control valve 20. The mixing chamber 18 comprises an oxygen metering orifice 21, spaced acetylene metering orifices 22, and a mixing orifice 23 connected through a conduit 23a to an annular chamber 29 leading through passages 30 to discharge orifices 31 in the nozzle 14. The orifices 31 diverge at an angle of about 5 degrees with respect to the axis of the oxygen jet, and may, alternatively, be replaced by an annular outlet passage. |
