Water jetting, also known as waterjet cutting technology (WJT), is a non-traditional cold cutting machine process that cuts materials such as wood, rubber, and plastic with a high pressure jet of water. This technology can also be applied to cut more rigid materials like granite and metals by adding an abrasive material to the water.
Waterjet technology was first introduced in the early 1950s, but its applications were limited. Modern water jetting technology is more sophisticated, as one would expect, given all the iterations made to the original prototype. As a result, it is now widely used in a variety of industries, including manufacturing and even for agricultural processes.
The Working Principle of Water Jetting Technology
Waterjet systems vary in design, but the majority include a cutting table that holds the material to be cut, a high pressure jetting pump, a nozzle that emits the jetstream, a cooling system, a sand supply system (for abrasive water jet systems), a motion system to move the jet head, and a computer-powered controller.
As a unit, a WJT's components collectively work to facilitate a high water pressure waterjet that cuts through materials. Its operation is based on the principle of water erosion; when a fast jet of water strikes the surface, the material is removed.
Here is a simple breakdown of the process from start to finish:
- The high pressure jetting pump generates a stream of water with a pressure rating of up to 6,800 bars (94,000 psi), which is up to four times the speed of sound. In more detail, a fire hose has a pressure range of 20 to 90 bars (390 to 1,200 psi).
- The water pressure is then converted into velocity via a tiny jet hole, resulting in a stream nearly as small as a strand of human hair, which then cuts through the material.
Industrial Applications of Water Jetting Technology
Many industries have creatively used water jetting technology to increase the efficiency of their cutting, reaming, and shaping of raw materials such as foam, composite, rubber, leather, paper, textiles, plastics, glass, stone, and others over the years.
Here is a look at some of those applications:
Waterjet technology is widely used in aerospace because it doesn’t have the drawbacks of other cutting processes such as laser cutting.
In fact, it is standard practice for most major aircraft manufacturers to use only waterjet technology to cut net-shaped parts and the rear parts of an aircraft that are deemed flight- or structural safety-critical. Waterjet cutting is also used to create components for turbine blades, jet engines, and aircraft composite materials.
The main reason for this preference for waterjet cutting in aircraft manufacturing is that hot process cutting can destroy and compromise the cut material's integrity.
Also, the lack of heat-affected zones in waterjet cutting eliminates the risk of microscopic cracks or warping in the parts which could, in turn, pose safety hazards. Furthermore, waterjet technology allows for the cutting of metals with high thermal conductivity (such as steel and aluminium) with minimal heat transfer.
This significantly reduces time spent on the expensive cutting process in production, thereby lowering costs for the aircraft manufacturer.
Waterjet cutting is popular in the automotive industry for a variety of reasons.
For starters, waterjet cutting provides automotive manufacturers with a great deal of flexibility. As the parts must be uniform, they can easily adjust the water jet settings to fit the precise requirements needed to create a specific part accurately every time. This is why waterjet technology is such an ideal solution, as there can be no room for error.
Furthermore, because WJTs are used on production lines in the automotive industry, a single cutting station can be outfitted with more than one abrasive or cutting head and robot. This means that the production line can process various parts made of different materials without stopping to change anything other than the control program. This can help reduce both production time and costs.
For decades, waterjet technology has been used in the agricultural industry’s manufacturing process to cut various types of produce such as celery, romaine lettuce, green beans, and more.
Water jet technology adds value by cutting products in a sanitary environment and reducing cross contamination that occurs in blade-cutting systems — meaning it eliminates the risk of metal shards getting into produce. What's more, because no knife blades are ever used, there is no downtime spent sharpening or replacing dull blades.
Because of the same reasons, the United States Department of Agriculture (USDA) equipment approval has been granted for the use of waterjet cutting systems in agriculture to facilitate a hygienic, nearly bacteria-free cutting process during production.
Architecture and Art
tWater jetting systems are probably most creatively used in the architecture and art industries. It should come as no surprise that waterjet cutting is ideal for these industries because it can cut through very thick materials while also being able to create irregular shapes with accuracy and speed.
This eliminates secondary finishing and operations, produces precise and smooth edges, and creates less waste than other traditional cutting methods used in these industries. WTJs are, therefore, ideal for cutting one-of-a-kind, custom designs.
Oil and Gas
Waterjet technology is being used in the oil and gas industry to improve operational efficiency and generate cost savings. It is also used to reduce operational breakdowns due to its increased accuracy and success rate.
The system provides enhanced performance with minimal downtime and a smaller operational footprint. It provides an innovative method for the internal removal and cutting of deepwater tubular structures ranging from jacket legs and piles to well heads and casings.
The most recent water jetting systems used in this industry also include performance enhancements such as visual external cut monitoring, real-time cut verification, and increased flexibility. These systems enable external cutting systems to fulfil specific requirements, assisting in the removal of impediments that can render other cutting tools ineffective.
The Future of Water Jetting Technology
The outlook points to more industries adopting water jetting technology in their operations. It is, after all, the ultimate tool for a lot of industrial applications.
The dynamics of high-speed, pulsating water from the high pressure jetting pumps produce incredible benefits for not just cutting applications but also for surface preparation and industrial cleaning applications as well.