How Waterjet Works
The energy required for cutting materials is obtained by pressurizing water to ultra-high
pressures, and forming an intense cutting stream by focusing this high-speed water
through a small, precious-diamond orifice.
There are two main steps involved in the waterjet cutting process. First, the ultra-high
pressure pump or intensifier pressurizes normal tap water at pressure levels up
to 60,000 psi (4,137 bar); to produce the energy required for cutting. Second, water
is then focused through a small precious diamond orifice to form an intense cutting
stream. The stream moves at a velocity of Mach 3, three times the speed of sound,
depending on how the water pressure is exerted. The process is applicable to both
water only and abrasive jets.
For abrasive cutting applications, abrasive garnet is fed into the abrasive mixing
chamber, which is part of the cutting head body, to produce a coherent and an extremely
energetic abrasive jet stream.
Cutting harder materials requires adding a fine mesh abrasive to the cutting stream.
Various abrasive materials which can be used include olivine, garnet, and corundum
with a particle size of between 50 to 120 mesh (0.2 to 0.5 mm). When abrasive is
required, KMT Waterjet provides an abrasive unit consisting primarily of an abrasive
hopper, an abrasive feeder system, a pneumatically controlled on/off valve, and
the abrasive cutting nozzle which contains the specialized mixing chamber.