What is the water jet cutter?
A water jet cutter, also known as a water jet or waterjet, is an industrial tool capable of cutting a wide variety of materials using a very high-pressure jet of water, or a mixture of water and an abrasive substance. The termabrasivejet refers specifically to the use of a mixture of water and abrasive to cut hard materials such as metal or granite, while the terms pure waterjet and water-only cutting refer to waterjet cutting without the use of added abrasives, often used for softer materials such as food or rubber.
Waterjet cutting is often used during fabrication of machine parts. It is the preferred method when the materials being cut are sensitive to the high temperatures generated by other methods. Waterjet cutting is used in various industries including mining and aerospace for cutting, shaping, and reaming.
An important benefit of the water jet is the ability to cut material without interfering with its inherent structure, as there is no "heat-affected zone" (HAZ). Minimizing the effects of heat allows metals to be cut without harming or changing intrinsic properties.
Water jet cutters are also capable of producing intricate cuts in material. With specialized software and 3-D machining heads, complex shapes can be produced.
The kerf, or width, of the cut can be adjusted by swapping parts in the nozzle, as well as changing the type and size of abrasive. Typical abrasive cuts have a kerf in the range of 0.04″ to 0.05″ (1.016 to 1.27 mm), but can be as narrow as 0.02″ (0.508 mm). Non-abrasive cuts are normally 0.007″ to 0.013″ (0.178 to 0.33 mm), but can be as small as 0.003″ (0.076 mm), which is approximately that of a human hair. These small jets can permit small details in a wide range of applications.
Water jets are capable of attaining accuracies down to 0.005″ (0.13 mm) and repeatabilities down to 0.001″ (0.025 mm).
Due to its relatively narrow kerf, water jet cutting can reduce the amount of scrap material produced, by allowing uncut parts to be nested more closely together than traditional cutting methods. Water jets use approximately one half to one gallon per minute (depending on the cutting head's orifice size), and the water can be recycled using a closed-loop system. Waste water usually is clean enough to filter and dispose of down a drain. The garnet abrasive is a non-toxic material that can be recycled for repeated use; otherwise, it can usually be disposed in a landfill. Water jets also produce fewer airborne dust particles, smoke, fumes, and contaminants[30], reducing operator exposure to hazardous materials.
Meatcutting using waterjet technology eliminates the risk of cross contamination since there is no contact medium (namely, a blade) between different animals in the slaughterhouse.

Edge quality for water jet cut parts is defined with the numbers 1 through 5. Lower numbers indicate rougher edge finish; higher numbers are smoother. For thin materials, the difference in cutting speed for quality 1 could be as much as 3 times faster than the speed for quality 5. For thicker materials, quality 1 could be 6 times faster than quality 5. For example, 4″ thick aluminium Q5 would be 0.72 ipm (18 mm/min) and Q1 would be 4.2 ipm (107 mm/min), 5.8 times faster