Oxy-fuel gas cutting, oxy-propane cutting and steel profiling

Flame cutting is a process known by many names, such as oxy-fuel gas cutting, oxy-propane cutting and steel profiling.

The process utilises a torch which an ignited mixture of oxygen and a fuel gas (such as propane) are passed through. An outer ring of jets in the torch nozzle are used to preheat the surface of the steel. A separate pure oxygen stream is directed from a central jet on to the area to be cut. Rapid oxidation of the steel takes place and material is removed by the pressure of the gases.

Flame Cutting Benefits

  • Can cut through thicknesses beyond the capability of plasma
  • Utilising multiple cutting heads provides a quick turnaround on flame cut profiles
  • Flame cutting is economical and quick to set up, with minimal down time

Flame Cutting Tolerances

Thickness Tolerance
Thickness tolerance for profiling shall be in accordance to BS EN 10029:1991 Class A.

Flatness Tolerance
Profiling flatness tolerance shall be in accordance to BS EN 10029:1991.

Profiling Tolerances for Lengths and Widths

Rectangular
For rectangular profiled steel plates, where length L, is defined as the greater of the two dimensions, tolerances on length and width shall be as given in Table 1.

Non-rectangular

For non-rectangular profiled steel plates, tolerances will be as given in Table 1, where length L shall be assumed to be the maximum dimension of the part in question.

Circles and Rings
For profiled steel circles and rings length L, will be understood to be the outside diameter of the part in question and tolerances will be as given in Table 1.

All profiling tolerances given in Table 1 are inclusive e.g. 4mm shall be understood to mean +/-2mm, but by arrangement may be defined as +4/-0mm or +0/-4mm.

Table 1. – Length and Width Tolerance for Profiled Steel Plates

 

LENGTH L

Material Thickness

Under 500mm

500mm to under 1500mm

1500mm to under 3000mm

3000m and over

Up to 10mm

3mm

3mm

3mm

4mm

Over 10mm to 25mm

3mm

3mm

4mm

5mm

Over 25mm to 50mm

3mm

4mm

4mm

5mm

Over 50mm to 100mm

4mm

5mm

5mm

6mm

Over 100mm to 200mm

5mm

5mm

6mm

6mm

Over 200mm

5mm

6mm

6mm

6mm

 

Dimensional Squareness
For rectangular profiled steel plates, where length L is defined as the greater of the two dimensions, the difference between the two diagonally opposite corner to corner dimensions shall be no greater than those shown in Table 2.
For non-rectangular shaped profiled steel plates, due to the difficulty in defining squareness, any specific requirement should be agreed with Charles Day Steels Ltd prior to order placement.


Table 2. – Dimensional Squareness Tolerances for Profiled Steel Plates

 

Difference between the corner to corner dimensions for Length L

Material Thickness

Under 1000mm

1000mm to Under 2000mm

2000mm to Under 3000mm

3000mm and over

Up to 40mm

4mm

5mm

6mm

7mm

Over 40mm to 100mm

5mm

5mm

6mm

7mm

Over 100mm

6mm

6mm

7mm

8mm

 

 

Profiling Edge Squareness
The deviation for edge squareness accuracy, W, for profiled steel plates shall not exceed the value shown in Table 3.


Table 3. – Profiling Edge Squareness

Material Thickness

Deviation W

Up to 10mm

0.5mm

Over 10mm to 25mm

1mm

Over 25mm to 50mm

2mm

Over 50mm to 100mm

3mm

Over 100mm to 200mm

4mm

Over 200mm

5mm