A waterjet is a metal cutting tool that uses a high-pressure stream of water. It may sound crazy, but an extremely powerful water jet has enough force to cut through metal.
You should imagine a waterjet as a device that spits out water at about 30 times the pressure of the pressure washer used at your local car wash. If you’ve ever used these services, you probably know that power washing can effectively remove dirt and grim from the surface of your car, as well as from its wheel rims and tires.
If you want water to cut through metal, you need to secure the coherence of the spray. Waterjets have the ability to cut because they channel the spray through an extremely narrow nozzle at unbelievably high pressure. This is how they manage to keep the spray coherent. The biggest advantages of a water cutter over metal cutters is that it never gets dull and it doesn’t overheat in the cutting process.
The first low pressure waterjets were used in the gold mines in California, back in 1852. In the early 1900s, people discovered steam and hot waterjets and used them for cleaning purposes. During the 1960s, high pressure waterjets were used in the mining industry, but it’s only 10 years ago that waterjets started to be used for cutting purposes. Abrasive water jets were already known and used in industry around 1980.
In the past, it was only possible to cut one piece of metal at once, either with a saw or by using some other metal cutting equipment. These processes were laborious and extremely expensive. Today, computer-controlled waterjet and abrasivejet devices are used in most industries to cut a wide array of soft and hard materials. The water-based abrasive mixture passes through the nozzle at an impressive speed of almost 1,000 mph. The most advanced equipment can cut at jet speeds in the Mach 3 range.
Materials that can be cut with waterjets:
- Marble, granite and other types of stone
- Various types of metals, including stainless steel
A water jet is able to cut a stack of different materials with a total thickness of up to four inches, or you could use any steel cutting band saw machinery. This dust-free, odorless and almost heat-free process can be used to cut a sheet of material as thin as a small fraction of an inch. In this situation, one single cut is everything that’s needed for obtaining the final finished surface. This process can save both material and machining costs.
Waterjets are suitable for cutting materials with lower hardness, while abrasive jets are more appropriate for materials with higher hardness values. Sometimes, the cutting occurs under water, in order to minimize splash and noise. Faster feed rates are effective in preventing the jet from, cutting all the way through.
The pressure of the water is usually between 20,000 and 55,000 PSI. The jet has to pass through a 0.010″ to 0.015″ in diameter hole in a jewel nozzle.
When adding SUPER-WATER (a soluble polymeric chemical developed by Berkeley Chemical Research), a waterjet can be used to remove the bark from trees. This can be an extremely effective solution to cut down roadside weeds.