A spray nozzle is a simple device used to break apart a fluid flow into a spray pattern. There are 5 basic spray pattern types: flat fan, solid stream, full cone, hollow cone and mist/fog. A number of different nozzle designs are available to produce these spray patterns and most nozzle design types can be configured to produce more than one spray pattern type. The design of the nozzle will have a significant effect on the other characteristics of the spray such as droplet size.
The nozzle selection process
When trying to select the most appropriate nozzle for a particular application it is often best to start with the desired spray pattern and then investigate which nozzle designs will best produce the other required spray characteristics. For this reason we have organised this section of the Bete Limited website into subsections corresponding to the 5 basic pattern types with an additional section covering tank cleaning nozzles and a 7th section detailing air atomising nozzles (which can produce any spray pattern).
Flat fan nozzles
Flat fan nozzles produce a line of spray. They are often used in coating and cleaning applications on conveyors where product is passed under a spray bar of several fan nozzles. There are two main designs of fan nozzle: deflection and a standard shaped orifice.
Hollow cone nozzles
Hollow cone nozzles produce a ring of spray. This spray pattern will generally consist of the smallest droplet sizes of any spray pattern. Three designs of nozzle can be made to produce hollow cones: spirals, axial whirls and tangential whirls.
Full cone nozzles
Full cone nozzles produce a solid circle of spray. These nozzles are used when the objective is to distribute the fluid evenly over an area. As with the hollow cone nozzles there are three designs of nozzle that can produce full cone patterns.
Mist or fog patterns are characterised as having the fluid finely atomised with little or no momentum. A homogeneous fog is produced that will largely be directed by any surrounding air flows rather than by the nozzle itself. There are two design types that produce this pattern: impingement and small orifice.
The straight jet pattern concentrates the fluid into a high impact dot of spray. The aim of such nozzle is generally to deliver as much impact as possible for cleaning or cutting applications. Other low impact uses can for the precision deliver of fluid to specific parts of a process. There are two design type for this pattern a standard shaped orifice nozzle and an
enhanced laminar flow design.
The tank cleaning "pattern" requires fluid to be delivered to the whole area of a vessel that needs cleaning. Typically this means a 360o delivery of fluid. There are 3 basic designs of tank cleaner that will achieve this: rotary jet cleaners fro high impact, rotary fan cleaner for medium impact and static cleaners for low impact.
Air atomising is not a pattern as such. The use of air to break apart a fluid is a fundamental change to the way standard pneumatic nozzles operate and so air atomisers warrant their pattern section. All patterns, except solid stream, can be created by air atomising nozzles and there are various designs variants within the group.
Spray nozzle pattern vs design chart
The interactive chart below summarises which designs of nozzle are capable of producing the 5 basic spray patterns. By moving the mouse over the chart you can click through to the relevant parts of this website. Please feel free to download and use the image below, if you wish to publish this on your own website then all we ask is that a link back to this page is added to credit the author.