What waterjet technology covers
Waterjet technology is the umbrella term for processes in which water is forced at high pressure through a narrow orifice. The resulting jet removes material, cuts through it, or releases deposits. The water is not a coolant or an auxiliary medium — it is the tool itself.
What matters for process selection is cold machining. There is no microstructural change at the cut edge, no distortion from heat input, and no temper colouring. This is why waterjet is used where thermal processes reach their limits — hardened steels, composite materials, glass, or explosion-hazard areas, for example.
The jet exerts force on the workpiece, but negligible clamping force. Thin, delicate, or irregularly shaped parts can be machined without being rigidly fixed. Conversely, that same force acts back on the tool as reaction force. Hand-held applications are therefore subject to their own set of rules.
The three process families
Practically everything that falls under waterjet technology belongs to one of three families. They differ less in pressure than in whether a solid medium is added to the jet, and whether the goal is cutting or surface treatment.
| Family | Typical Pressure | Tool at the Jet | Task |
|---|---|---|---|
| Pure-water jetting | 2,000–6,000 bar | Water orifice, 0.08–0.30 mm | Cutting soft materials: gaskets, foam, textiles, food, paper |
| Abrasive waterjet | 3,000–6,000 bar | Water orifice plus focusing tube, garnet added | Cutting hard materials: steel, titanium, glass, stone, composites |
| High-pressure water jetting | 100–3,000 bar | Flat, rotor, or rotary nozzle | Surface treatment: cleaning, coating removal, concrete removal, pipe and tank cleaning |
The first fork in any project is between pure water and abrasive. It drives system architecture, operating cost, and which materials are reachable. That choice is covered under Pure Water or Abrasive. How the systems behind it are built is covered under System Types.
Pressure ranges for orientation
Pressure alone says little about performance. Only combined with flow rate does it yield the hydraulic power at the tool. Still, the following bands are a useful rough guide.
| Pressure Range | Applicable Standard | Typical Task |
|---|---|---|
| up to 350 bar | EN 60335-2-79 | Commercial high-pressure cleaning: facades, vehicles |
| 350–1,000 bar | EN 1829-1 | Industrial cleaning, coating removal, light concrete removal |
| 1,000–3,000 bar | EN 1829-1 | Concrete removal, pipe and tank cleaning, deburring |
| 3,000–6,000 bar | EN 1829-1 | Cutting with pure water and abrasive |
A rough guide for orientation, boundary per the currently valid edition DIN EN 60335-2-79:2015-02 (35 MPa / 350 bar); this figure has applied since the European edition EN 60335-2-79:2009. Only the earlier IEC editions IEC 60335-2-79:1995 (edition 1) and IEC 60335-2-79:2002 (edition 2) set this boundary at 25 MPa (250 bar), a figure still seen in older literature. The boundaries are otherwise not sharp; the manufacturer's specification and the risk assessment govern the classification of any specific unit.
At the upper limit of EN 60335-2-79 — 35 MPa, or 350 bar, under the currently valid edition DIN EN 60335-2-79:2015-02 — the applicable standard changes. Below it, the standard for high-pressure cleaners applies; above it, EN 1829-1 for high-pressure water jet machines. This is not a formality: the requirements for protective devices, hoses, and briefing change with the standard. Only the earlier IEC editions IEC 60335-2-79:1995 and IEC 60335-2-79:2002 set this boundary at 25 MPa (250 bar); anyone relying on older sources or older equipment should check which edition applies. Covered in detail under Standards and Directives.
Related terms: common points of confusion
Several terms sound similar but describe fundamentally different things. The following table clears up the three most common mix-ups.
| Term | What It Means | Relationship to Waterjet Technology |
|---|---|---|
| Water-jet pump (aspirator) | A laboratory pump that uses flowing water on the Venturi principle to create a vacuum | No connection. It creates negative pressure rather than high pressure, and the achievable vacuum is limited by the vapour pressure of water. The pump in a waterjet system is called a high-pressure pump. |
| High-pressure cleaner | A unit up to the EN 60335-2-79 boundary (currently 350 bar) for cleaning tasks | Same basic idea, different standard, different order of magnitude. A high-pressure cleaner does not cut. |
| Waterjet cutting | The cutting process within waterjet technology | A subset, not a synonym. Cleaning, coating removal, and concrete removal are also part of waterjet technology but cut nothing. |
Where waterjet technology is used
Cutting sheet metal, composites, glass, and stone with no heat effect. The largest application block.
Removing burrs from bores and cross-drilled holes, often on parts that are otherwise difficult to access.
Stripping coatings, deposits, and residue without attacking the substrate and without abrasive waste.
Selective removal of damaged concrete down to the reinforcing steel, which the process leaves undamaged.
Interior cleaning of pipelines, heat exchangers, and vessels using rotating tools.
Removing support structures and powder residue from geometrically complex parts.
A complete overview with the relevant constraints is available under Applications.
Strengths and limits
Waterjet is not a universally superior process. It wins where heat input is prohibited or material variety is required, and loses where part count and speed are what matter.
| Criterion | Waterjet | Laser | Plasma |
|---|---|---|---|
| Material independence | |||
| No heat input | |||
| Cutting speed on thin sheet | |||
| Large material thicknesses | |||
| Edge quality without rework | |||
| Operating cost per hour | |||
| Reflective materials |
Qualitative rating for typical tasks, not measured values. The specific part decides in any individual case.
A detailed comparison, including the question of hourly rate, is available under Waterjet vs. Laser and Operating Costs.
Where to go next
Depending on why you're here, a different page is the right next step.
- You want to understand how a system worksSystem Technology: process chain, hydraulics, operating point, and tool, considered together.
- You are planning a procurementPrepare a selection and the requirements specification, so quotes become comparable.
- You are working out an operating pointThe operating-point calculator returns flow rate, power, and reaction force, with an assessment against DGUV Rule 100-500.
- You are responsible for safe operationSafety, plus Standards and Directives, with the applicable thresholds and issue dates.
- You are costing a jobOperating costs, with a cost model and calculator per machine hour.
- You've run into an unfamiliar termThe glossary explains the terminology and converts the units.
Frequently asked questions
What is waterjet technology, in one sentence?
What pressure do you need?
What is the difference between a waterjet system and a waterjet cutting system?
Which materials can be processed?
Is the process suited to single parts or to series production?
How loud and how messy is it?
- DIN EN 1829-1:2021-04, High-pressure water jet machines – Safety requirements – Part 1: Machines – https://www.dinmedia.de/de/norm/din-en-1829-1/321847498
- DGUV Rule 100-500, chapter 2.36 – Working with Liquid Jetting Equipment, issue March 2017 – https://publikationen.dguv.de/media/pdf/27/3a/6a/R500_236.pdf
- Regulation (EU) 2023/1230 on machinery, applicable from 20 January 2027 – https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32023R1230