How waterjet cutting works
How does waterjet cutting work?
Abrasive Waterjet Cutting is essentially an accelerated erosion process. Ultra-high pressure water is fired through a ruby or diamond orifice into a “mixing chamber” which creates a vacuum and draws garnet sand into the water stream. This means waterjet is an extremely powerful and versatile cutting tool, which is used globally for a wide range of waterjet cutting applications.
How does the waterjet pump generate ultra-high pressure water?
1. The process begins at a large electric driven oil pump, which pumps oil at 2750 psi into a heavy duty intensifier (pressure amplifier) assembly.
2. Inside the intensifier that the pressure is increased from domestic supply pressure (50-60 psi) up to 55,000 psi. This increase in pressure is achieved due to the greater surface area of the hydraulic piston (20 times the surface area of the water piston) to amplify water pressure to 20 times the pressure of the oil.
3. The ultra high pressure water is then fed via stainless steel pressure piping into a cutting head on a profile cutting table.
4. At the cutting head, the stream of high pressure water is focussed through a ruby, sapphire, or diamond orifice which focusses the water into a fine "needle."
5. The ultra high pressure water is then fired through a mixing chamber where abrasive garnet sand is drawn into the waterstream.
6. The abrasive and water mixture then exits the cutting head through a focussing tube at speeds up to mach 2, thus creating a highly efficient and powerful cutting tool.
What is the difference between pure water cutting and abrasive water cutting?
Pure water (non-abrasive waterjet) cutting technology is primarily used for cutting soft materials such as rubber, foam, gaskets, leather, textiles and food. Water is pressurised to ultra-high pressure levels and forced through a small ruby, sapphire or diamond orifice to form an intense cutting stream. The jet stream moves at a velocity of up to 2.5 times the speed of sound, creating the ability to cut at very high feed rates, creating a very effective and powerful precision cutting tool.
Abrasive waterjet cutting: For hard materials that cannot be cut with water only, the water nozzle is replaced with an abrasive cutting head. The high velocity water stream creates a vacuum which draws the abrasive into a mixing chamber, producing a coherent, powerful abrasive jet stream. This process is ideal for cutting any material in sheet or slab form including mild and stainless steel, aluminium, sheetmetal, composites, decorative stone, synthetic ceramics and glass.