Since the dawn of time, water has always proven itself to be a high-precision cutting material. It erodes mountains, levels out plains, and transforms basically any topography. And recent developments in technology have only fine-tuned this excellent characteristic: one of the most prominent of these is the waterjet machine.
What is a waterjet machine?
Simply put, a waterjet machine is a piece of equipment that utilises a high-pressure stream of water for cutting. In its earliest forms, the technology involved low-pressure water that was used to cut paper. Then in the 1940s, high-pressure seals were developed for the hydraulic and aviation industries. A decade after, numeric controls were added, and plastic materials joined the list of materials the equipment could work on.
In the 60s, high pressure pumps started being manufactured for the polyethylene industry; 10 years later, the first commercial pump was released. Fast forward to the 21st century, and industrial operators can now choose from several models with differing capacities for motion control systems, monitoring, and even 3D tools.
How does it work?
A waterjet machine is available in two major types: pure and abrasive. The main difference between the two is that the latter incorporates a garnet abrasive at its orifice, thereby commissioning it for a wider range of use.
Both pure and abrasive waterjets work virtually the same though. Imagine a stream of water from the tap pressurised up to 60, 000 psi, exiting from a tiny hole at high speed. First, there is an ultrahigh pressure pump that generates water with pressures of up to 94,000 psi. (For reference: a fire hose can generate a stream that can only go up to 1,200 psi.) This pressure is then converted into velocity with the use of a small jewel orifice, which results in a hair-like stream of water. Within abrasive waterjet machine, you enter garnet into the mix, and the result is you have a stream that exits the cutting head of the equipment at about four times the speed of sound.
The result is superfast, supersonic water that can cut through a variety of materials, and the process has turned into one of the most useful industrial strategies that has proven its worth across multiple industries.
What is it used for?
An abrasive waterjet machine is used to cut or clean many materials, among the most popular of which are metals like aluminum. Waterjets can wield intricate shapes into metal sheets, with high precision. The process is also more economical, as there is a smaller margin for error when waterjets are used for the purpose. Stone and glass are also favourable, especially for artists who intend to create highly personalised art pieces that would have been tough to pull off with traditional machining methods.
Pure waterjets, on the other hand, are used for softer materials. These include food, rubber, and foam.
Waterjets – abrasive or otherwise – however, cannot cut into diamond and tempered glass. Diamonds are the hardest materials known to man, while tempered glass will shatter if it is so much as disturbed.