Calculator
Example Data Table
| Thickness | Total Cut | Fuel | Speed Used | Total Time | Oxygen Used |
|---|---|---|---|---|---|
| 12 mm | 10.000 m | Acetylene | 0.500 m/min | ~26.0 min | ~0.25 Nm³ |
| 25 mm | 6.000 m | Propane | 0.279 m/min | ~26.7 min | ~0.38 Nm³ |
| 50 mm | 4.000 m | Natural gas | 0.175 m/min | ~30.5 min | ~0.50 Nm³ |
Example values are illustrative; use your torch charts for precise planning.
Formula Used
- Total cut length: Ltotal = Lper × N
- Cut time: tcut = Ltotal ÷ v
- Pierce time: tpierce = (tpierce,per × N) ÷ 60
- Torch time: ttorch = tcut + tpierce + tpreheat
- Total time: ttotal = ttorch + tsetup
- Oxygen used: O2 = (FO2 × tcut) + 0.60×FO2×(tpreheat+tpierce)
- Fuel used: G = (Ffuel × tcut) + 0.75×Ffuel×(tpreheat+tpierce)
- Costs: C = (O2×cO2) + (G×cfuel) + (rlabor×ttotal/60) + overhead%
How to Use This Calculator
- Choose the material and fuel gas used on site.
- Enter thickness, cut length, and the number of cuts.
- Add realistic setup, preheat, and pierce times.
- Use Auto modes for a quick estimate.
- Switch to Manual modes for chart-based planning.
- Enter gas prices, labor rate, and overhead if needed.
- Press Calculate to view results above the form.
- Download CSV or PDF for a shareable job record.
Professional Notes for Oxy Fuel Cutting Planning
1) Scope and Assumptions
This calculator estimates cutting time, oxygen and fuel consumption, and job cost for oxy fuel cutting. It targets carbon and low alloy steels where oxidation supports cutting. Speeds and flows are practical estimates, not manufacturer settings.
2) Speed versus Thickness Benchmarks
Cutting speed decreases as thickness rises because more heat must be delivered to maintain a continuous kerf. Typical planning values for steel are about 0.8–1.2 m/min at 6 mm, 0.25–0.35 m/min at 25 mm, 0.15–0.20 m/min at 50 mm, and 0.08–0.12 m/min near 100 mm. Use your torch chart for critical work.
3) Oxygen Demand Trends
Oxygen is the main process gas. Higher thickness needs higher oxygen flow and longer cut time, so total oxygen volume grows quickly. A simple planning model is O2 flow that increases with thickness, then multiplies by cutting time, with reduced flow during preheat and piercing.
4) Fuel Selection Impacts
Acetylene tends to preheat faster and can improve speed on thinner plate. Propane and natural gas often cost less per unit energy but may require higher fuel flow and different tips. For planning, compare fuels using the same cut length and thickness and review the resulting time and gas volumes.
5) Time Structure on Site
Total time includes setup, preheat, piercing, and travel cutting. Setup can dominate short cuts because layout, clamping, and checks take minutes even when cutting takes seconds. If you are producing repeated parts, capture your average setup time once and reuse it for consistent estimates.
6) Cost Drivers and Estimating
Gas cost is oxygen plus fuel volume multiplied by their unit prices. Labor cost is operator time times hourly rate, and overhead can be applied as a percentage. Add contingency when thickness is high, access is limited, or plate condition is unknown; speed and pierce time vary.
7) Quality, Kerf, and Distortion Control
Heat input increases when speed is low or thickness is high, raising distortion risk. Keep speed stable, use correct tip size, and avoid excessive preheat. If edge squareness matters, test a short sample and adjust speed and oxygen for a smooth, slag free cut.
8) Reporting and Continuous Improvement
Export CSV or PDF to store job records with thickness, length, time, and gas use. After several jobs, compare planned versus actual values and tune manual speed and flow entries. This feedback loop improves estimating accuracy and helps standardize crew performance across sites.
FAQs
1) Which materials are best for oxy fuel cutting?
It works best on carbon and low alloy steels that oxidize readily. Stainless and aluminum typically do not cut well with this process and are usually handled with plasma, laser, or mechanical methods.
2) Should I trust Auto speed and flow values?
Use Auto for early planning and quick comparisons. For production, switch to Manual and enter values from your torch chart, because tip size, pressures, and plate condition can shift speeds and gas rates.
3) Why does thickness reduce cutting speed so much?
Thicker plate needs more heat to sustain ignition along the kerf and to eject slag effectively. That requirement lowers travel speed and often increases piercing time, which raises total torch time.
4) How can I reduce gas consumption on a job?
Use correct tip size, keep torch height and speed steady, and minimize unnecessary preheat time. Good fit up and clean surfaces help maintain a stable cut, lowering rework and extra torch time.
5) What does the heat input index indicate?
It is a planning indicator that increases with thickness and decreases with speed. Higher values suggest more impact and a greater chance of distortion on long cuts or thin members.
6) How do I estimate repeated cuts accurately?
Enter the cut length for one part and set the number of cuts. Measure typical setup and handling time for your crew, then reuse those values. This captures real field time beyond pure cutting.
7) Can I use this for bevel cuts or complex shapes?
You can approximate by increasing cut length and adding extra piercing and setup time. Bevels, tight radii, and stops usually slow travel speed and increase rework risk, so manual tuning is recommended.
Plan smarter cuts, reduce waste, and improve job accuracy.