Lesson documents - Career and Technical Education

4. Bleed the acetylene hose and regulators, then close the torch valve (bothgauges will drop to zero).5. Screw out the acetylene regulator adjusting screw until loose.6. Turn off the oxygen cylinder valve.7. Bleed the oxygen hose and regulators and close the torch valve (both gaugeswill drop to zero).8. Screw out the oxygen regulator adjusting screw until loose.9. Recheck the valve and roll up the hose. If rig is not to be used for some time,remove the regulators and put the safety caps back on the cylinders.II. Lab 2:PROCEDURE FOR TURNING ON THE OXYFUEL RIG1. Valves on the torch body should be closed.2. The adjusting screws on the regulators must be loose.3. Turn on acetylene cylinder valve ¼ to ½ turn; if wheel type, open all the way.4. Tighten the regulator adjusting screw to the desired working pressure.5. Open the oxygen cylinder valve all the way.6. Tighten the regulator adjusting screw to the desired working pressure.7. If the cutting attachment is being used, open the torch body oxygen valve allthe way.8. Crack the acetylene valve and light. Blow the flame off the tip and slowlyadjust in back.9. Adjust to a neutral flame with the oxygen valve. The oxygen pressure can be 5to 10 times higher than the acetylene pressure when cutting. Never exceed 15pounds pressure per square inch on acetylene. When welding, the ratio ofoxygen to acetylene is approximately 1:1. Oxygen and acetylene settings willvary depending on the attachment tip and thickness of metal to cut or weld.Guided Practice (LSI Quadrant III):ApplicationCopyright © Texas Education Agency, 2012. All rights reserved.4