Cut with pure water or add an abrasive – it all depends on the material

Very low setting times and lots of flexibility in use

Flexible cutting heads are an important feature of modern water jet cutting systems. The cutting heads should be easy to maintain and as flexible as possible to use. That means that cutting with both pure water and with abrasives should be possible without lengthy setting times. It is important to use a cutting head whose wearing parts (particularly the focusing nozzle) can be replaced easily.

For cutting with pure water, the cutting head consists of a needle valve, the nozzle tube and the nozzle itself. This is made of a precious stone, with diamond or sapphire being most commonly used. This is because the nozzle is exposed to the highest stresses and therefore has to be extremely hard and resistant. Diamond inserts in the nozzles have a 15 to 20 times longer service life than a sapphire nozzle, thus reducing the frequency of down and resetting times even further. If you wish to cut with both pure water and with abrasives, you should always use a diamond nozzle.

Prevent turbulence in front of the water nozzle

Another important point for quality when cutting with pure water is the design of the cutting head. The water in the nozzle tube flows at extremely high speed. This causes turbulence in front of the water nozzle. And this turbulence has a massive influence on the length of the bundled water jet. Great turbulence results in the water jet widening early after it leaves the nozzle and thus loses energy. The longer the jet remains bundled, the better the cut quality and the higher the cutting speed can be – important criteria for cutting efficiently and cost effectively with pure water. Pure water is generally used to cut thick, soft materials. Turbulence in front of the water nozzle and a widening jet cause grooves in these materials at the jet discharge side. Developments in the high pressure pump sector mean that it is now possible to cut aluminium up to around four millimetres thick using pure water without abrasives and a 6000 bar water jet.

Do you need a flexible system for water jet cutting using pure water or added abrasives? Write to us. We have advised many customers and have always found the right system for them. Simply send a mail to info@gkteso.de