KMT Waterjet is the most recognized waterjet pump in the World. Companies in a variety of industries have been using KMT Waterjet cutting products with great effectiveness for more than 40 years. Thanks to its flexibility and reliability, waterjet technology is suitable for both large nesting productions as well as small series and complex specialized applications. Every day, innovative companies are discovering new applications for waterjet cutting, extending their production capacities and increasing their efficiency and profits.
The commercial success, growth and survival of many companies and job processors who cut, form and machine materials are based on the use of waterjet machine cutting in their processes.
What are the advantages of waterjet cutting as opposed to other cutting methods?
- Very fast implementation from drawing board to cut piece
- Short setup time - as tangential forces are minimum, workpieces need normally not be clamped
- High precision - no need for costly recutting
- High cutting speeds
- No need for resharpening tools
for the operator and the environment - waterjet cutting does not
produce vapours or dust and the method does not require costly coolants
- Cold cutting method - does not affect the structural properties of the material
- Clean end product - no need for reworking
- Burr-free cutting edges - no need for reworking with most waterjet applications
- Small cutting gaps
method for the production of prototypes and production processes that
require high flexibility - successfully used in large serial production
- Optimised utilisation of material with CAD/CAM software
- Customised system solutions
HIGH PRESSURE PUMP TECHNOLOGY
The waterjet pump has been called the heart of the water jet system, pressurizing the water to thousands of pounds per square inch and then pushing it through to the cutting head, where it will be emitted at high velocities through a tiny orifice. With such an important role to fill, the pump must be able to meet high usage demands and precision requirements.
The Intensifier Principle
An electric motor drives a hydraulic pump that pressurises the fluid
circuit of the intensifier. There, the pressure is then increased
twenty-fold and transferred to the high pressure water system.
The water is drawn from the local supply
network and pressurised by a booster pump to max. 7 bar. It
then is fed through a filter system into the high pressure cylinder of the
intensifier. The pressure intensifier includes a
primary circuit which operates at 200 bar by means of an electrically
driven hydraulic pump. The fluid is pumped alternately through a
four-way valve to the right-hand or left-hand side of the hydraulic
The two piston rods installed in the
hydraulic piston apply pressure to the water in the two high pressure
cylinders of the intensifier. These are part of
the secondary water circuit. Suitably dimensioned check valves on both
ends of the high pressure cylinders control the input of fresh water
into the cylinders and the supply of cutting water to the pump outlet.
The water pressure of approx. 6200 bar is generated through a piston
surface ratio of around 38:1. The high pressure pumps are equipped with
an accumulator (pressure peak compensator) that ensures that the high
pressure signal at the outlet of the high pressure pump remains more or
less constant during the change of direction of the hydraulic piston.
The high pressure pump is connected through a high-strength stainless
steel pipe to the cutting head. The sapphire or diamond orifice in the
cutting head focuses the pressure into an ultrafast waterjet (speeds of
approx. 800 to 1000 m/s).
To cut hard materials, the cutting
power of the waterjet can be increased by adding an abrasive. In such
units, abrasive, water and air are mixed in the mixing chamber of the
cutting head, collimated in the focusing nozzle and accelerated. The
resulting high-energy jet is capable of micro-eroding, i.e. drilling and
cutting, materials of great thicknesses and of the most diverse
consistencies, such as metals, ceramics, rock and bulletproof glass.
CUTTING HEAD TECHNOLOGY
Pure Water & Abrasive
Pure Water Cutting Heads
Water is fed through specially designed pressure-proof flexible pipelines to the cutting head. The cutting head consists of a pneumatically operated valve and a nozzle tube with a precious stone orifice (normally made in sapphire or diamond) at its outlet. The cutting jet exits the orifice at up to three times the speed of sound.
Abrasive Cutting Heads
A special abrasive head is mounted on the water nozzle. In this head, the abrasive is mixed with the pressurized water. The movement of the cutting head is normally CNC controlled through the waterjet cutting unit. Early detection leakage points protect the orifice body, nozzle pipe and nozzle nut against damage, as they indicate if connections must be retightened or seals replaced. Thanks to the unique design of the cutting head, seals can be replaced in less than five minutes and without tools. The precision performance combined with easy maintenance of KMT Waterjet abrasive cutting heads offer unrivaled value. Thanks to the simple design, orifices can be changed in seconds without the need for any tools!
Waterjet cutting with pure water or abrasive
With waterjet cutting, soft materials are normally cut with pure water, while harder materials are processed with a mixture of water and abrasive.
Waterjet cutting with pure water
This method is primarily used for soft materials such as plastics, textiles, paper, sealing materials, metal foils, plywood, food, etc. Normal tap water is pressurised and forced through a small precious stone orifice, so that a highly powerful cutting jet is produced. This jet exits the orifice at a speed of up to three times that of sound and can be used to cut materials at high cutting speeds (determined by the properties of the material).
SAMPLES OF PURE WATER CUT PARTS
Abrasive cutting methods are used for hard materials such as metal, glass, minerals, concrete, glass composites, ceramics, aluminium or silicone oxide. In other words, abrasive is added where pure water is unable to cut the material properly. In the abrasive cutting process, abrasive (consisting of fine particles) is added to the waterjet. In the cutting head, water, air and abrasive are mixed together and forced through the focussing tube at high speed. The resulting high-energy jet is capable of micro-eroding, i.e. drilling and cutting, materials of great thicknesses and of the most diverse consistencies, such as metals, ceramics, rock and even bullet-proof glass.
SAMPLES OF ABRASIVE WATERJET CUT PARTS