How Do Water Jets Manage To Cut Through Steel?

Water jet cutting has amazing capabilities but how is that possible?

How can it be that a jet of water can cut through steel, or granite, or marble – and do so with great accuracy?

When we tend to think of jets of water we might imagine the hose pipe, or perhaps a jet washer. The latter is a powerful jet but it isn’t about to cut through metal – it wouldn’t be much use for cleaning the car if it did.

The most simple explanation is that water jet cutting can be so effective simply because of the pressure and the focussed nature of the jet.

The jet itself is incredibly focussed, it is forced through a narrow cutting head. The pressure is enormous, the water jet coming through at pressures of up to 87,000 PSI. To put that into context, an expensive home pressure washer might deliver up to 2,000 PSI.

The coherence of the stream is also critical, the stream delivered is completely consistent and unlike metal cutting it cannot overheat, nor does it sullen or need sharpening. As long as there is a water supply, the cutter can continue working.

The water does, though, have a little help. Mixed into the flow is an abrasive garnet, this aids the cutting but it is environmentally neutral  and so easily disposed of – another key benefit of water jet cutting is that it is effective, but also more environmentally friendly than other technologies.

Water jet cutting accuracy

The accuracy of the cutting head and the water pressure explain why the cutting process can cut almost any shape into bullet proof glass, or cut the parts for stealth bombers. The cutting can also typically do this in one cut, there is no need for multiple cuts, what is delivered is a cut through up to 25cm of almost any material, but with complete accuracy.

Beyond all this, what is perhaps more remarkable is that water jets can also undertake delicate jobs.

While they might be associated with cutting steel or other dense materials, professionals water jet cutting can also be used to make art and has been instrumental in creating some stunning sculptures (if you’ll allow us a moment to mention our own work, we worked on projects at both the V&A Museum and the Whitworth Art Gallery).

The versatility is possible because various aspects of the cutting can be tweaked. The water pressure can be lowered, the cut could be purely water without the abrasive garnet.

The speed the part to be cut is delivered can also be altered, faster delivery leading to a shallower cut.

And for those of you who prefer visual learning, here is a superb video from the How Stuff Works website, showing just how water jet cutting works.

Water Jet Cutting Video

Can water jet cutting handle your job?

Without wishing to sound arrogant, almost certainly! Water jets can cut through almost any material and that to a depth 10 times greater than a laser can manage. Advanced water jets can also cut complex 3-d parts in one fluid motion.

If you would like to discuss any jobs you might have, please do get in touch with us at TMC Waterjet, we love discussing all things water jet! You can mail info@tmcwaterjet.co.ukor call us on 01625 610 441.