GENERAL WATERJET CUTTINGINFORMATION
Water jets were used to mine for gold in 1870 already. But only the progress of pumps has made it possible to increase water pressure to now cut all kinds of materials.
In the beginning of the 1980ies, mixing in solid particles was the latest innovative step in waterjet technology for the time being. It makes it possible to process virtually all materials with pure or abrasive waterjets.
- No thermally caused change in the cut material
- Optimal material use through small cutting gaps
- The cut can be started and stopped in the material
- Easy handling through low reaction forces
- Two-dimensional and areal cutting possible
- Direction-independent work possible
TWO PROCESS VERSIONS
Generally, there are two different process versions: cutting with pure waterjets and with abrasive waterjets. Both methods can be used for cutting as well as cleaning and removal. Depending on the material, different cutting edge qualities can be achieved with waterjet technology depending on the selected parameters.
Unlike cleaning technology applications where widespread and even removal matters most of all, the jets used for cutting with water are bundled as closely together as possible. Jet diameters range from 0.1 to 0.5 mm. The pressure to generate the required energy density in the jet is up to 6,000 bar. This complies with the pressure at the bottom of a 6,000 m water column. Depending on the material, thicknesses of up to 300 mm can be but with pure waterjets.
The energy density of pure waterjets is not sufficient for the processing of many technical materials. Solid particles are therefore added to the waterjet for the respective applications. This makes it possible to also process materials that cannot be cut with pure waterjets or to significantly increase cutting performance as compared to working with pure waterjets.
The so-called abrasives are essentially sharp-edged, mineral substances like granite sand or olivine with grain sizes from about 0.1 to 0.3 mm. Depending on the cutting application, the required abrasive quantity is 100 to 800 g/min. Just like cutting with pure waterjets, pressures of up to 6,000 bar are used for abrasive waterjets. The jet diameter is between 0.3 and 1.2 mm. The application limit in view of material thickness for cutting with abrasive waterjets is about 300 mm.