Nozzle wear is indicated by an increase in nozzle capacity and by a change in the spray pattern, in which the distribution (uniformity of spray pattern) deteriorates and increases drop size. Choice of a wear-resistant material of construction increases nozzle life. Because many single-fluid nozzles are used to meter flows, worn nozzles result in excessive liquid usage.
Many applications use two-fluid nozzles to achieve a controlled small drop size over a range of operations. Each nozzle has a performance curve, and the liquid and gas flow rates determine the drop size. Excessive drop size can lead to catastrophic equipment failure or may harm the process or product. For example, the gas conditioning tower in a cement plant often utilizes evaporative cooling caused by water atomized by two-fluid nozzles into the dust-laden gas. If drops do not wholly evaporate and strike a vessel wall, dust will accumulate, resulting in the potential for flow restriction in the outlet duct, disrupting the plant operation.
The construction material is selected based on the fluid properties of the liquid to be sprayed and the environment surrounding the nozzle. Spray nozzles are most commonly fabricated from metals, such as brass, Stainless steel, and nickel alloys. Still, plastics such as PTFE, PVC, and ceramics (alumina and silicon carbide) are also used. Several factors must be considered, including erosive wear, chemical attack, and the effects of high temperature.
Single-fluid or hydraulic spray nozzles utilize the kinetic energy imparted to the liquid to break it into droplets. This most widely used spray nozzle is more energy efficient at producing surface area than most other types. As the fluid pressure increases, the flow through the nozzle increases, and the drop size decreases. Many configurations of single-fluid nozzles are used depending on the spray characteristics desired.
Nozzles Nearly every industrial manufacturer can improve quality and efficiency with the right spray technology. Our 90,000+ spray nozzles are used in over 200 industries for cleaning, coating, cooling, drying, lubricating, dispensing, sanitizing, marking, and more. With an exclusive focus on spray technology and with more nozzles than any other supplier, Spraying Systems Co. has the expertise to help you solve your production challenges.
Internal mix nozzles contact fluids inside the nozzle; one configuration is shown in the figure above. Shearing between high-velocity gas and low-velocity liquid disintegrates the liquid stream into droplets, producing a high-velocity spray. This nozzle type tends to use less atomizing gas than an external mix atomizer and is better suited to higher viscosity streams. Many compound internal-mix nozzles are commercially used, e.g., for fuel oil atomization.
Every industrial manufacturer can improve quality and efficiency with the right spray technology. Our 90,000+ spray nozzles are used in over 200 industries for cleaning, coating, cooling, drying, lubricating, dispensing, sanitizing, marking, and more. With an exclusive focus on spray technology and with more nozzles than any other supplier, Spraying Systems Co. has the expertise to help you solve your production challenges.
Rotary atomizers use a high-speed rotating disk, cup, or wheel to discharge liquid at high speed to the perimeter, forming a hollow cone spray. The rotational speed controls the drop size. This technology’s most essential and expected uses are spray drying and spray painting.
A spray nozzle is a precision device that facilitates liquid dispersion into a spray. Nozzles are used for three purposes: to distribute a liquid over an area, increase liquid surface area, and create impact force on a solid surface. A wide variety of spray nozzle applications use several characteristics to describe the spray.