Cutting metals with water jet
For the cutting of metals, the waterjet cutting method is in direct competition with a number of established cutting methods such as laser and plasma cutting.
Waterjet cutting can however be used to cut thicker materials than can be processed with laser. On the other hand, it offers greater precision than plasma cutting. Waterjet cutting is a cold cutting process and therefore of particular interest for applications where the material may not be affected by heat. This is often a requirement in the aerospace and automotive industry.
Main advantages of cutting metals with waterjet cutting:
- No material deformation caused by heat
- No hardening of the material along the cut edge
- No changes to the metal structure
- No heat affected zones
- No hazardous fumes and vapours
- No or only minimal need for reworking
Comparison of cutting methods
| |
Laser |
Plasma |
Waterjet |
|
Warping / deformation |
yes |
yes |
no |
|
Material hardening |
yes |
yes |
no |
|
Burr formation |
yes |
yes |
minimal |
|
Need for reworking |
yes |
yes |
minimal |
|
Loss of material |
hoch |
yes |
minimal |
|
Tolerances |
0,1 mm |
0,2–0,5 mm |
0,1–0,3 mm |
|
Hazardous vapours |
yes |
yes |
no |
|
Multilayer cutting |
no |
no |
yes |
|
Material thickness |
< 25 mm |
< 30 mm |
> 250 mm |
|
Non.metallic materials |
no |
no |
yes |
|
Multi-head application |
no |
— |
yes |
|
Composites |
no |
no |
yes |
Cutting metal - frequently asked questions
-
Assuming that warping and changes to the metal structure are not an issue, what is the thickness from which waterjet cutting becomes the most cost-effective option?
Depending on the material, waterjet cutting should be considered as the most viable option from thicknesses of 5 to 8 mm.
-
How fast can the material be cut?
The cutting speed is determined by the following factors: pump pressure, efficiency of high pressure generation and cutting head configuration, material thickness and properties, desired cutting edge quality, orifice diameter, abrasive quantity and abrasive quality. See also cutting speed table below.
-
What is the maximum material thickness that can be cut with water jets?
For metals, the maximum thickness is normally 150 mm. Waterjet cutting is however also used in special applications where materials of up to 400 mm thickness are cut.
-
What about angle faults along the cut edge?
Depending on the requirements as regards cutting edge quality, excellent angle accuracy can be achieved by adjusting the pump pressure, the abrasive flow rate and the cutting speed accordingly. There are also software-based guiding systems on the market that help optimise angular accuracy, by adjusting the angle of the cutting head.
Cutting speeds
|
Abrasive flow rate |
350g/min |
|
Abrasive |
80 Mesh |
|
Quality of cutting edge |
fine - medium |
|
Orifice diameter |
0,25 mm |
|
Focussing tube diameter |
0,76 mm |
|
Pump pressure |
6.200 bar |
|
Material |
Thickness |
Cutting speed |
|
Steel |
20 mm |
50 mm / min |
|
|
|
|
Pump pressure |
4.200 bar |
|
Material |
Thickness |
Cutting speed |
|
Steel |
20 mm |
35 mm / min |
|
Steel |
10 mm |
120 mm / min |
|
Steel |
5 mm |
200 mm / min |
|
Titanium |
20 mm |
30 mm / min |
|
Titanium |
10 mm |
90 mm / min |
|
Titanium |
5 mm |
140 mm / min |
|
Aluminium |
20 mm |
75 mm / min |
|
Aluminium |
10 mm |
200 mm / min |
|
Aluminium |
5 mm |
350 mm / min |
KMT products for cutting metals with waterjet
KMT Waterjet Systems offers a range of high pressure pumps that cater for all applications. They cover everything from maximum cutting waterjet pressures of up to 6200 bar to maximum volumetric flows of more than 15 l/min and simultaneous operation of a large number of cutting heads.
- STREAMLINE 60/125 PRO – waterjet cutting with 6200 bar
- STREAMLINE SL-V 15-100
- STREAMLINE SL-V 30/50 Classic
- STREAMLINE SL-V 150/200
- ACTIVE AUTOLINE PRO – abrasive waterjet cutting head for 6200 bar
- ACTIVE IDE PRO – compact abrasive waterjet cutting head for 6200 bar
- ACTIVE AUTOLINE II – modular abrasive waterjet cutting head for 4100 bar
- ACTIVE IDE II – compact abrasive waterjet cutting head for 4100 bar
- AMS III – abrasive management system consisting of an ABRALINE III abrasive bulk transfer system, a FEEDLINE IV metering system and ACTIVE AUTOLINE II or ACTIVE IDE II cutting heads
- ABRALINE III – abrasive bulk transfer system
-
FEEDLINE IV – abrasive metering system
About KMT Waterjet Systems
KMT Waterjet Systems is a leading multinational manufacturer of waterjet cutting systems. The company develops complete solutions for a wide range of industries and applications. Since 1971 the company has been dedicated to long-term customer relationships. Continuous investment in innovation has made KMT Waterjet Systems the market leader in the waterjet cutting industry. High pressure pumps, cutting heads, abrasive systems, high pressure tubes, original spare parts and a global service network are among the key products and services of the company.