Water jet cutter

Waterjet technology evolved in the post-war era as researchers around the world searched for new methods of efficient cutting systems.

[4] In 1958, Billie Schwacha of North American Aviation developed a system using ultra-high-pressure liquid to cut hard materials.

[5] This system used a 100,000 psi (690 MPa) pump to deliver a hypersonic liquid jet that could cut high-strength alloys such as PH15-7-MO stainless steel.

In 1962, Philip Rice of Union Carbide explored using a pulsing waterjet at up to 50,000 psi (340 MPa) to cut metals, stone, and other materials.

[13] By the turn of the century, high-pressure reliability improved, with locomotive research leading to a sixfold increase in boiler pressure, some reaching 1,600 psi (11 MPa).

[15] Higher pressures in hydraulic systems in the oil industry also led to the development of advanced seals and packing to prevent leaks.

[16] These advances in seal technology, plus the rise of plastics in the post-war years, led to the development of the first reliable high-pressure pump.

The invention of Marlex by Robert Banks and John Paul Hogan of the Phillips Petroleum Company required a catalyst to be injected into the polyethylene.

[18] Flow Industries in Kent, Washington set the groundwork for commercial viability of waterjets with John Olsen’s development of the high-pressure fluid intensifier in 1973,[19] a design that was further refined in 1976.

The March 1984 issue of the Mechanical Engineering magazine showed more details and materials cut with AWJ such as titanium, aluminium, glass, and stone.

[23] Hashish, who also coined the new term abrasive waterjet, and his team continued to develop and improve the AWJ technology and its hardware for many applications.

A critical development was creating a durable mixing tube that could withstand the power of the high-pressure AWJ, and it was Boride Products (now Kennametal) development of their ROCTEC line of ceramic tungsten carbide composite tubes that significantly increased the operational life of the AWJ nozzle.

[24] Current work on AWJ nozzles is on micro abrasive waterjets so that cutting with jets smaller than 0.015 inches (0.38 mm) in diameter can be commercialized.

[23] By January 1989, that system was being run 24 hours a day producing titanium parts for the B-1B largely at Rockwell's North American Aviation facility in Newark, Ohio.

[35] A major breakthrough came in the early '90s, when John Olsen developed systems to precisely position the waterjet nozzle while accurately specifying the speed at every point along the path and utilizing common PCs as a controller.

A direct drive pump works much like a car engine, forcing water through high-pressure tubing using plungers attached to a crankshaft.

An intensifier pump creates pressure by using hydraulic oil to move a piston forcing the water through a tiny hole.

This beam of water is ejected from the nozzle, cutting through the material by spraying it with the jet of speed on the order of Mach 3, around 2,500 ft/s (760 m/s).

[40][41] 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 warping, affecting tempers, or changing intrinsic properties.

Water jets also produce fewer airborne dust particles, smoke, fumes, and contaminants,[44] reducing operator exposure to hazardous materials.

Materials commonly cut with a water jet include textiles, rubber, foam, plastics, leather, composites, stone, tile, glass, metals, food, paper and much more.

[50] Specially designed water jet cutters are commonly used to remove excess bitumen from road surfaces that have become the subject of binder flushing.

This can be useful for applications like weld preparation where a bevel angle needs to be cut on all sides of a part that will later be welded, or for taper compensation purposes where the kerf angle is transferred to the waste material – thus eliminating the taper commonly found on water jet-cut parts.