News Microwaterjet cutting, invented by Waterjet, combines the advantages of laser and water-jet technologies. Its application is widely used in different fields, such as the watch industry. Read on to learn more!
The firm Waterjet, based in Aarwangen (35 kilometres from Biel), has been offering its services for 25 years to different manufacturing sectors such as the medical, aeronautical, aerospace, automotive, glass, timber, textile, paper and watch industries, and even this list is not exhaustive. Work carried out ranges from simple cutting to more complex solutions such as milling, drilling, tapping, boring, etc. The company has its own laboratory where it develops new cutting processes or finds individual solutions to meet specific manufacturing requests from its customers.
Waterjet cutting - what is it?
The technology of waterjet cutting is not radically different from its normal jet counterpart. The technique is a thermally-neutral cold cutting process (relying on pure water or water charged with abrasives) and is used by manufacturers in micro-engineering. The differences lie essentially in the dimensions and accuracy of the cutting head and, for water charged with abrasive, the volume of the mixing chamber for blast particles.
Microjet cutting was developed by Walter Maurer (CEO of Waterjet SA) and his team. The process combines the precision benefits of laser-cutting with those of waterjet cutting: the material undergoes no stress or thermal constraints whatsoever, leaving its homogeneity and strength unaffected as a result.
The development of microwaterjet cutting technology was essentially the result of demand from the market, with precision engineering components showing a growing tendency in recent years towards miniaturisation and the use of highly complex materials.
The process
The microwaterjet cutting process does not differ greatly from its macro counterpart. Generally a CAD-CAM drawing suffices to start the machining process, together with parameters for the material, its thickness, and the quality of cut required. A long series of continuous optimisation and development phases have made it possible to reduce the cutting jet (4,000 bar, 3 times the speed of sound) to a diameter of 0.17 mm. Positioning accuracy for its part is less than a micron.
The capacity of the cutting table is 1,000 x 600 mm. Cutting accuracy depends on the material and also its thickness, while tolerances are in the order of + or – 0.01mm, or 0.005 mm for boring.
The advantages
Microjet cutting economizes on resources and allows cost savings. The consumption of water and abrasives drops from 0.4 litre/minute to 0.17 litre/minute, and from 60 g/minute to 16 g/minute respectively. Moreover the energy required to produce 4,000 bar has been halved, to 3 kW. Because the work is carried out without specific tools, tooling costs are eliminated, even for short production runs.
Alongside more common materials, microjet cutting can be used for micrometric precision cutting of heat-sensitive materials, special materials and exotic alloys. There is virtually no limit to the materials that can be machined.
The level of mechanical stress to which the material is subject is very low. Costly support systems are unnecessary. Cutting without pre-stressing prevents structural modification of the workpiece, allowing ultra-thin cutting widths. On structured surfaces and for engravings, cutting can now proceed without deburring or subsequent treatments, producing a level of surface quality of up to Ra = 0.8 µm.
Exclusive technology
In its laboratory, Waterjet has developed the unique AWJmm microwaterjet cutting process, the most precise in the world in its category. This exclusive technology combines the advantages of waterjet cutting with the precision of YAG laser cutting.
Located in German-speaking Switzerland, the company Waterjet has a branch in the neighbouring French-speaking region manned by Pascal Messerli (info@waterjet.ch and 079/102 86 42). For more information visit www.waterjet.ch or www.microwaterjet.ch.
June 13, 2014
