| 摘要 |
PURPOSE:To perform simultaneous slag processing surely without causing turbulence of cutting gas flow by blowing gas containing oxygen from slit holes of a pair of slit nozzles at right angles to the cutting groove from back side of a steel material in gas cutting. CONSTITUTION:Parallel with advance of gas cutting of a steel material 1 by a cutting torch 2, gas is blown from the back of the steel material 1a following advance of cutting using a slit nozzle 8 having a nozzle hole 9 and slag is processed simultaneously. The slit hole 9 of above-mentioned slit nozzle 8 consists of a pair of slit holes 9, 9' provided symmetrically at right angles to the cutting groove 4. The length W is 1.2-5 times as long as the cutting width S and an interval (d) 0.8-1.5 times as long as the cutting width is provided by a blocking plate 10 between them. Gas containing more than 50% of oxygen is blown to the position M 20-150mm. off backward from the tip of cut point 0 at an upward angle theta of 10-25 deg. from the rear direction of advance of cutting. |
