In broad terms, a waterjet is a machine that uses a high-pressure jet of water to cut through materials. Waterjets can cut through anything from cardboard and rubber to metal and stone. In order to understand the amount of pressure waterjets operate under, let’s put it into perspective. An average kitchen sink faucet can put out water at a pressure of up to 60 psi, or maximum pounds per square inch. Waterjets, however, put out water at a pressure of 90,000 psi.
There are two different types of waterjets: pure and abrasive. Pure waterjets use only water to apply pressure and work best with softer materials like plastic and foam. Abrasive waterjets add abrasive particles, typically garnet, into the stream of water so that it can cut through tougher materials like glass and metal. Because of its ability to cut through almost anything, the waterjet quickly gained popularity for its versatility. Waterjets also surpass competing cutting methods in efficiency, speed, and environmental impact.
Waterjet cutting was first used in the 1850’s to excavate materials in coal mines in New Zealand and Russia. This hydraulic mining technique was then adapted by coal miners in California and was used to find the gold that hid beneath rock. At this time, steam power allowed the water to reach a pressure of 800 psi. Over the years, more pressure was able to be applied, allowing more materials to be cut with the waterjet cutting method.
By the beginning of the 20th century, workers were able to reach 1600 psi, doubling the amount of water pressure they had started cutting with. The first time waterjet cutting was used in an industrial setting outside of mining was in the 1930’s. Leslie Tirrell and Elmo Smith invented a jet-stream technique and the paper industry started utilizing waterjet cutting to cut their paper. In 1935, Smith came up with the idea of adding abrasive particles to the water stream in an effort to allow the waterjet to cut through tougher materials.
In the years since people first began using water to cut through materials, the waterjet has come a remarkably long way. In the 1950’s, an engineer named Norman Franz began experimenting with adding abrasive particles to high-pressure water systems in an effort to cut lumber. His findings proved that abrasive waterjets were effective in cutting through harder materials than had previously been used.
By the late 1950’s, engineers had developed a system that was able to get the water pressure up to 100,000 psi, which was an incredible breakthrough in the evolution of the waterjet cutting method. This system involved a pump with a hypersonic liquid jet with the ability to cut through high-strength alloys like stainless steel. While this method was not an effective one, it allowed researchers to expand upon the idea of using waterjet cutting to cut through even the strongest of materials.
In the 1970’s, the invention of the crystal waterjet orifice allowed the waterjet cutting method to be commercialized. Created by the Bendix Corporation, crystal orifices helped bring waterjets mainstream. This version of the waterjet was able to reach a water pressure of 60,000 psi. While they were expensive, they were still viewed as being more cost-effective than the traditional cutting methods used in manufacturing.
One of the most relevant breakthroughs in the history of the waterjet came in the 1980’s when Mohamed Hashish, an Egyptian engineer, developed a nozzle for abrasive waterjet cutting that was suitable for commercial use. In the last forty years the waterjet cutting system has been constantly improved upon, making it as precise, efficient, and versatile as possible. The capabilities of the waterjet are always evolving as the manufacturing industry continues to push the boundaries of what it can do.
As with any form of technology, there are countless researchers and manufacturers who are constantly seeking to improve the waterjet cutting machine. Over the years the waterjet has been commercialized, made more cost-effective, more versatile, and smaller in size. In coming years, you can expect to see waterjets used on an even larger scale as newer and more cost-effective models continue to pop up. From an efficiency standpoint smaller machines tend to be viewed as more appealing, so you can expect to see engineers developing smaller waterjet cutting machines in the future. As the titan of the cutting industry, waterjets certainly aren’t going anywhere.