Vannstråle

Vannstråle, in English often referred to as a water jet, is a stream of water produced by forcing water through a nozzle at high pressure. The term can refer to several related technologies, including high‑pressure cleaning jets, waterjet cutting, and waterjet propulsion in ships and other machinery.

A water jet is generated by a high‑pressure pump that increases the water’s pressure, sometimes using a series of stages or an intensifier to reach tens to hundreds of megapascals. The pressurized water passes through a small nozzle, converting hydraulic energy into kinetic energy and creating a high‑velocity jet. In some systems, a secondary nozzle shapes or stabilizes the jet. For abrasive water jets, the stream is mixed with hard particles (such as garnet) to improve cutting capability.

Common applications include surface cleaning and preparation, where the jet removes paint, rust, or contaminants without chemicals; and waterjet cutting, where high‑pressure water (often with abrasives) cuts metals, stone, glass, or composites with high precision. Water jets can also provide propulsion in certain vessels and equipment, where the jet’s reaction thrust moves the craft or device.

Key properties of a vannstråle are its velocity, pressure, and flow rate, which determine its cleaning power or cutting capability. Safety considerations are important due to the risk of severe injury from high‑pressure fluids, and proper shielding and protective gear are standard in industrial settings.