How Waterjet Cutting Works

Introduction
In the battle to reduce costs, engineering and manufacturing departments are constantly on the lookout for an edge. The waterjet process provides many unique capabilities and advantages that can prove very effective in the cost battle. Learning more about the waterjet technology will give you an opportunity to put these cost-cutting capabilities to work.

Beyond cost cutting, the waterjet process is recognized as the most versatile and fastest growing process in the world (per Frost & Sullivan and the Market Intelligence Research Corporation). Waterjets are used in high production applications across the globe. They compliment other technologies such as milling, laser, EDM, plasma and routers. No noxious gases or liquids are used in waterjet cutting, and waterjets do not create hazardous materials or vapors. No heat effected zones or mechanical stresses are left on a waterjet cut surface. It is truly a versatile, productive, cold cutting process.

The waterjet has shown that it can do things that other technologies simply cannot. From cutting whisper thin details in stone, glass and metals; to rapid hole drilling of titanium; to cutting of food, to the killing of pathogens in beverages and dips, the waterjet has proven itself unique.

History of Waterjets
Dr. Norman Franz is regarded as the father of the waterjet. He was the first person who studied the use of ultrahigh-pressure (UHP) water as a cutting tool. The term UHP is defined as more than 30,000 pounds per square inch (psi). Dr. Franz, a forestry engineer, wanted to find new ways to slice thick trees into lumber. In the 1950's, Franz first dropped heavy weights onto columns of water, forcing that water through a tiny orifice. He obtained short bursts of very high pressures (often many times higher than are currently in use), and was able to cut wood and other materials. His later studies involved more continuous streams of water, but he found it difficult to obtain high pressures continually. Also, component life was measured in minutes, not weeks or months as it is today.

Dr. Franz never made a production lumber cutter. Ironically, today wood cutting is a very minor application for UHP technology. But Franz proved that a focused beam of water at very high velocity had enormous cutting power — a power that could be utilized in applications beyond Dr. Franz's wildest dreams.

In 1979, Dr. Mohamed Hashish working at Flow Research, began researching methods to increase the cutting power of the waterjet so it could cut metals, and other hard materials. Dr. Hashish, regarded as the father of  the abrasive-waterjet, invented the process of adding abrasives to the plain waterjet.  He used garnet abrasives, a material commonly used on sandpaper.  With this method, the waterjet (containing abrasives) could cut virtually any material.  In 1980, abrasive-waterjets were used for the first time to cut steel, glass, and concrete. In 1983, the world's first commercial abrasive waterjet cutting system was sold for cutting automotive glass. The first adopters of the technology were primarily in the aviation and space industries which found the waterjet a perfect tool for cutting high strength materials such as Inconel, stainless steel, and titanium as well as high strength light-weight composites such as carbon fiber composites used on military aircraft and now used on commercial airplanes.  Since then, abrasive waterjets have been introduced into many other industries such as job-shop, stone, tile, glass, jet engine, construction, nuclear, and shipyard, to name a few.