Acetylene Flow Rates For MC12 Cutting Tips

[joeslide]

Looking at the chart for selecting MC tips for given metal thickness. Am I reading this right? You can use a size 4 (145 CFM) acetylene cylinder to cut up to 6 inch thickness?

Thanks,
Joseph

[MMW]

Can you post the chart? Most charts I just looked at don't show a cylinder size reccomendation. However they do list consumption in scfh. I would say yes for a 4 tip but for a limited time, but the charts I see show a 4 tip used for up to 4" thick material, not 6".
I use victor brand and have run large cutting tips and rosebuds off of 145 cuft tanks as needed. You should be aware of your draw down when using large tips.

[joeslide]

The link is here:

https://americantorchtip.com/resources/cut-charts/

There's a drop down box. Choose "Oxy-Fuel - Smith".

Thanks,
Joseph

[MMW]

I looked at the chart and don't see anything about tank size? The Smith mc12 chart? The acetylene pressures stay roughly the same as you go bigger in tips. It's mainly the draw down you need to watch. You are only supposed to draw 1/7 of tank size. I have violated that rule a lot with out issue but that does not mean you won't have problems.

[joeslide]

Well, looking at the chart for MC12 tips, the second column is the metal thickness in inches. Let's consider the last row which is 6 inches of metal. That thickness requires a number 6 tip, 90 PSI of Oxygen, and 10 PSI of Acetylene. I'm assuming that the Number 6 tip will allow a flow rate 485 SCFH of Oxygen. I'm seeing where the 1/7 rule for maximum flow out of acetylene is now the 1/10 rule. Given a 145 CFM of acetylene, the maximum flow out is 145 divided by 10 which equals 14.5. In column 8 of the chart, the specified flow rate is 13 SCFH which is less than 14.5. Am I correctly reading the chart for its intended purpose? If you look at a chart for Victor tips, its the acetylene that must be increased proportionately with metal thickness - I don't know why though. It might be where in the torch the gases are mixed?

Thanks for your response.

Joseph