AES APPLICATION GUIDE ________
Waterjet technology is a relatively new abrasives technology that was first introduced in the United States in 1984 by Flow International, a spin off company of Waterjet Technology Inc. Because high pressure water can be effective for cleaning, a portion of the waterjet industry fits with the blast cleaning industry, grouped with air-abrasive cleaning applications. High pressure water cuts many materials effectively and is used extensively by the food and paper industry. Most headliners for new cars, for example, are cut with this waterjet technology. Mix abrasives with high pressure water and you have an effective tool to cut metals and nonmetal materials. This is the abrasives waterjet technology covered by this page. This type of application is typified by products of Flow International
Abrasive waterjet methods can be theoretically divided into entrainment systems and abrasive slurry systems. The key difference between the two technologies rests on how the abrasives is added to water. An entrained system pressurizes water and pulls abrasive particles into the rapidly moving stream on exit. The mixture of water and abrasives is focused in a mixture tube and directed at the work piece. An abrasive slurry system mixes water and abrasive before the water is pressurized. Lower pressures, very high material removal rates, and less expensive equipment are advantages of this type of system. The chief disadvantage is the wear on all parts of the system. Wear in an entrained waterjet system is limited to the mixing tube portion of the waterjet head.
Abrasive slurry waterjet was first popularized by the British Hydraulics Research Groupwhich established the name DIAJET for the technology. Generally slurry systems have less precision and are more commonly used for rough cutting processes where the high material removal rates and cool cutting are important attributes. The only US maker of these systems is U.S. Jetting Inc.
The success of the abrasive waterjet systems for precsion cutting rests upon development of the mixing nozzle and the precision controls in robotic and gantry systems. The development of the Roctec nozzle by Boride Products extended life of nozzles from a few hours to roughly 150 hours. The Roctec 100 nozzles is made from a special solid carbide material developed to have no binder.
For a recent article on waterjet cutting see the December 1997 issue of Tooling and Production.
Recent technical Papers from the Society of Manufacturing Engineers.
MR95-186 Abrasive Suspension Jet Machining by Ralph Resnick, Extrude Hone Corporation
MR95-189 Abrasive Waterjet Systems for Production Applications by Steve Madden Regional Sales Manager, Flow International.
TEXTBOOKS:
1. Summers, D. A.:Waterjetting Technology. 1st edition. London: Spon 1995
2. R.A. Tikhomirov, V.F. Babanin, E.N. Petukhov, I.D. Starikov, V.A. Kovalev:High-Pressure Jetcutting. ASME Press, New York 1992.
Please sent correction and additions to the Abrasive Engineering Society
rev 5/1/15