in Class with the Ironworkers: Oxy-Fuel Cutting Tips

During the week of July 18, a team of ESAB experts attended the 32nd Annual Ironworker Instructor Training Program, held at Washtenaw Community College, Ann Arbor, Mich. Hundreds of Ironworkers from around the United States and Canada attend this "train the trainer" event. With their new knowledge and skills, participants return to their local training halls better able to help the next generation of Apprentices turnout as Journeymen.

ESAB conducted two classes at this year's show, with one focused on plasma cutting and another focused on oxy-fuel training. The oxy-fuel training event covered essential safety rules, proper equipment set up, cutting advice and correct shutdown procedures. Here are 13 tips that cover highlights from the oxy-fuel training class (and for a fun video, check out the winner of the I-beam plasma cutting contest, who was a student in the plasma cutting class).


Stand AsidIronworkers: Oxyfuel tips - Stand asidee - When slowly opening the cylinder valve, always stand to the side of the regulator. In the (highly unlikely) event the regulator fails, it would be most prone to fail in a manner that directs the force of the gas in the direction of the regulator bonnet and PA knob. Then open the oxygen cylinder valve all the way, but only open acetylene valves 1/2 to 1 full turn. Open alternate fuel cylinder valves all the way. 

 

Ironworkers: Oxyfuel tips 3Leak Test - Use a wrench to tighten all metal-to-metal connections, including the ones between the gas hoses and the torch. Next leak test the connections by saturating (not wetting – saturating!) them with leak test fluid and watching for growing bubbles. Use approved leak test solution.

 

 





Ironworkers: Oxyfuel tips - Right size tipRight Size Tip - For the best cut quality, use the right size tip for the metal thickness at hand and adjust gas pressure according to the tip charts for your specific brand of cutting outfit. Note that flow rates may vary between brands, so refer to the tip chart if you're not familiar with a torch.

 

 

 

 

 

Ironworkers: Oxyfuel tips - Pressure DropPressure Drop - When using narrow diameter and/or long lengths of hose, consider that the gas pressure will drop by the time it reaches the torch. You can find pressure drop charts in the Victor gas equipment catalog (PDF page 16 in the online version and page 12 in the print version). Compensate for the pressure drop by increasing the regulator delivery psig to make sure back-of-the-torch pressure meets cutting tip requirements.

 

Ironworkers: Oxyfuel tips 2Gauges On the Handle - If you consistently cut at long distances from your cylinders, it's a good idea to verify the exact pressure drop for your rig. Attach pressure test gauges, such as the ones shown here, and note the difference between pressure at the cylinder outlet and at the torch; increase psig at the regulator until the gauges at the torch match the desired pressure.

 

Ironworkers: Oxyfuel tips 1Brace Yourself - In whatever way possible, support your cutting hand with your freehand. Here, this Ironworker shows a little innovation by propping up a piece of scrap on which to brace his freehand.

 

 

Ironworkers: Oxyfuel tips - Ready to pierceReady to Pierce - Before you can pierce steel with the cutting oxygen flame, you need to be sure that the steel has reached its kindling point. While the reddish-yellow color is a good indicator, you can confirm temperature by gently and slightly depress the cutting oxygen lever. If the steel forms slag on top of the plate immediately, you're good to go and can fully depress the level. If the metal doesn't burn, release the cutting oxygen lever and maintain the pre-heat flame a little longer.

 

Ironworkers: Oxyfuel tips - Spiral outSpiral Out - When piercing, start in the center and work outward toward your cutting path.




Ironworkers: Oxyfuel tips - Torch HeightTorch Height - Generally, hold the torch so that the inner cones of the acetylene flame are just off the cutting surface, as shown in the larger photo. That said, alternate fuels are more forgiving in torch height, which has been exaggerated in the inset shot for demonstration purposes.

 

 

Ironworkers: Oxyfuel tips - Roll in Roll outRoll In, Roll Out - When cutting thicker metal, "roll" the torch into the edge of the metal and then bring it perpendicular. At the end of the cut, roll the torch outward to help ensure a clean sever.








Lighting Alternate FuelsLighting Alternate Fuels - Propane has a different density than air, so it tends to "float" away from the torch tip. If you have trouble lighting the torch, especially in windy conditions, hold the torch against the plate at a 45-degree angle so the plate "traps" the gas. Once lit, introducing the pre-heat oxygen can also extinguish the flame — which happened shortly after this photo was taken. If the flame goes out, relight the torch and hold tip against the plate at a 45-degree angle and slowly introduce pre-heat oxygen until the flame snaps into place.


Ironworkers: Oxyfuel tips - Secured cylinderSecured Cylinders - It's all too easy to forget to secure cylinders when moving them around a job site. If you don't have a cylinder cart handy, try a reinforcing column!

 

 

Ironworkers: Oxyfuel tips - Oxygen First, Fuel LastOxygen First, Fuel Last - Victor recommends shutting off the torch oxygen valve first, then closing the torch fuel valve. This technique leak checks both valves every time the torch is shut down. A snap or a pop indicates a leaking oxygen valve, while a small flame at the end of the tip indicates a fuel gas leak.

 

 

For companies, unions and other instructors who would like to conduct their own oxy-fuel training class, ESAB, through its Victor brand, offers a complete instructional DVD. The DVD includes 36-minutes of visual instruction, as well as an instructor guide and student reference materials. To obtain a copy of the Victor Oxy-Fuel Safety Video, contacting your local ESAB representative and request literature item 65-2505.


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