Comparing sheet metal techniques: what to choose?
In cases when the manufacturing technique is not the key factor, or it is not known at the moment (many subcontractors face this), many other factors should be considered. Today, both punching presses and different cutting units ( laser, flame, plasma cutting) are popular on the the sheet metal market.
Laser cutting technology is a competitive player, comparing with shearing and punching techniques. It is especially visible when coming to processing very thin materials (up to 6 mm thin). Laser cutting machines are very efficient and profitable, if a manufacturer focuses on producing small batches of complicated shape parts.
Punching presses should better be used for production of large and middle-sized rectangle parts, with some forming elements required. The ability not only to punch holes, but form them is a significant bonus, and it can be the turning point of decision for some companies.
We have compiled several tables listing advantages and disadvantages of machines that use these techniques. Depending on the manufacturer, machine parameters may change or do not be that explicit.
The table data is statistically average and should be considered as recommendation only.
LASER CUTTING
Advantages |
Disadvantages |
No tooling required | Slow working speed |
Simplicity and quick setup | Large investment in the beginning |
Cutting complicated contours | High energy consumption |
Minimum material waste | |
Narrow cutting | |
Cutting path optimization | |
Cutting hard-to-cut sheets | |
Small micro-wrinkles | |
Low noise | |
No deformation |
PUNCHING
Advantages |
Disadvantages |
High productivity and low price | Large tooling expenses |
Efficient for large and middle-sized part batches | Tooling wear-off |
Smaller investment in the beginning | Long setup time |
Forming functions | Higher level of noise |
You can cut sheet metal using different kinds of matters - a laser beam, oxygen (flame) or plasma.
Laser cutting gains its popularity thanks to a minimum deformation of sheet, ability to achive minimum cut width and a higher level of accuracy. Also, laser-cut parts are well-suited for automatic welding due to accuracy of size. Please see a comparison table of different kinds of cutting below.
The table data is statistically average and should be considered as recommendation only.
Cutting type |
Oxygene (flame) |
Plasma |
Laser 2,5 kWt |
Laser 6 kWt |
Energy source | oxidizing | plasma | light | light |
Energy consumption | low | average | high | high |
Sheet metal | Steel | Steel, stainless, aluminum | Steel, stainless, aluminum | Steel, stainless, aluminum |
Steel cutting speed (mm/min) | low (500) | high(2700) | average(1400) | average(2100) |
Cut width (mm) of 12 mm thick steel | average (1,5) | large (3,0) | small (0,5) | small (0,8) |
Size accuracy, mm | from 1,0 to 2,0 | from 0,5 to 1,0 | 0,2 | 0,2 |
Straightness error on 30 mm wide strip | 1,5 | 3,0 | 0,4 | 0,4 |
Straightness of cut surface | good я | poor | high | high |
Surface quality | acceptable | good | acceptable | acceptable |
Top edge flame-polishing | acceptable | poor | good | good |
Environment pollution | acceptable | high | low | low |
Investment at the beginning | low | average | high | high |
Maintenance costs | high | high | average | average |
IMA information:
Italian Machinery Association offers both punching machines and machines for different kinds of cutting. You can find more information about them in our equipment catalog, or by contacting us.