It is true that waterjets are used for common materials such as steel, aluminum, gasket, and foam. But many people feel the tougher applications are where waterjet really shines. In this post I’ll highlight some that I believe best illustrate waterjet and abrasive waterjet capability.

1. Stone
2. Composites
3. Exotic metal: Titanium and Inconel
4. Thick insulation
5. Cement board

The first three are abrasive waterjet related, and the last two use pure waterjet.

Stone cutting with waterjets

Kitchen and bathroom countertops are often made of granite, marble, or engineered stone (usually a quartz and epoxy resin combination). The initial pattern of stone countertops are often cut with abrasive waterjet.

Stone inlays are artistic pieces used to beautify floors of hotel lobbies, borders around rooms, table tops, or other decorative pieces in architecture. The abrasive waterjet is used heavily in these applications. Whenever you see ornate geometry such as vines, flowers, leaves or complex geometry in a stone inlay it almost always was cut with an abrasive waterjet. Alternative methods for cutting stone in these applications include saws, routers and grinding. The abrasive waterjet’s thin stream and the fast and simple art to part sequence frees designers from nearly all manufacturing limitations. Very detailed cutting patterns are possible.

Waterjets in composite cutting

Composites are highly engineered materials, usually selected for use because of their strength to weight ratio. They are stronger than metal per pound (but lighter in weight), delivering a weight reduction that’s highly desirable in the transportation and sporting industries.

Composites such as fiberglass and carbon fiber reinforced plastic are challenging to saw, mill, rout, or burn. The material is comprised of usually two components; some type of resin epoxy and cloth made of fibers. The epoxy can burn and the fibers can become damaged during cutting. Engineers using composites want to avoid epoxy burning, micro cracks, and delamination, as well as fiber pull out, breakage, and whiskers. All of these problems are avoided when cut with the abrasive waterjet. The gentle supersonic erosion process removes small amounts of material at high speed, where no heat has time to be transferred and the forces are very localized. Abrasive waterjet is used to trim composite boat hulls for personal watercraft, cut sporting goods products, trim automobile components, and cut huge commercial airplane parts and small airplane clips and parts.

Waterjet cutting of exotic metals

A lot of mild steel (carbon steel) and aluminum are cut in the world today. As a result, abrasive waterjet cuts a lot of mild steel and aluminum. However, exotic metals used in advanced applications cut extremely well with abrasive waterjet technology, yet pose real problems for other cutting processes. Titanium is much harder and lighter than steel, and are used in applications such as aircraft and places where weight should be reduced. Nickel alloys (steel with nickel added) are very stable at high temperatures and are often used in engines where the component should not enlarge or deform with extreme heat.

Milling titanium alloys or nickel alloys is difficult because the cutting process with a mill is very slow, generates a lot of heat, and quickly wears out the bit. Abrasive waterjet is often used to either produce highly accurate finished parts, or to rough cut a part to a good tolerance to later be finished on the mill (thereby reducing processing time and saving expensive material due to the thin kerf cut of abrasive waterjet). A Flow waterjet, for example, can cut titanium faster than steel, and nickel alloy at approximately the same speed as steel.

Cutting insulation material with waterjet

Insulation material used in  HVAC, automotive, or in the walls of buildings and homes can be difficult to cut, often utilizing some type of fiberglass, either crushed or very “fluffy.” A pure waterjet can cut fiberglass very quickly, even the very thick fiberglass insulation that you might use in the attic of your home. Patterns are cut in the HVAC and automotive industries, and simple slitting is performed on the thick and fluffy insulation cutting with pure waterjet.

Cement board cutting with waterjet

Cement board is commonly used today as a building product. Usually between 1 to 3 cm thick, it provides strength, moisture resilience, and can be formed into various shapes. It is generally used for building siding, substrate for wall tile, or as underlayment for floors. Cement board can be cut with a saw, which is the obvious cutting tool of choice at the job site. However, in the factory it is often desirable to cut the cement board when it is in an uncured state, sometimes called a green state. Here is where the pure waterjet shines.  Much like slitting paper, the pure waterjet can easily be integrated into the manufacturing line to slit the cement board before final curing. And similarly to stone material, the abrasive waterjet can be used to cut cement board into intricate shapes after the cement board has been cured (hardened).

When it comes to tough applications, the pure waterjet and the abrasive waterjet really shine. The gentle supersonic erosion and very thin cutting stream provide manufacturers with a versatile and capable tool.
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