High Pressure Misting Nozzles Explained

Misting nozzles come in a variety of shapes and sizes. It is often asked, “Why so many and what are the differences?” The purpose of this blog is to answer these questions and define the performance capabilities of the misting nozzles offered by Mosquito and Cooling Systems.

Impellar nozzles are the most common misting nozzle and they have been used in the misting industry for over 50 years. A well designed and machined impellar style nozzle will provide droplets ranging from a few microns up to about 50μ with the majority of the droplets being larger than 10μ.

Although there have been improvements to impellar misting nozzles over the last 20 years, the basic performance and function has not changed. Essentially, the impellar style nozzles are designed to atomize the water flow into tiny droplets. These nozzles utilize a barrel shaped impellar, a small orifice, and a vortex shaped interior to force the water through the nozzle in such a way that it explodes through the small opening in a circular motion resulting in billions of tiny individual droplets.

When placed in a series along a length of tubing or onto the facing of a fan, the water is absorbed by the air and evaporative cooling takes place. If the nozzles are placed in an enclosed area, increased humidity levels are achieved.

Standard mist nozzles versus Cleanable mist nozzles

There are two basic types of impellar nozzles, cleanable and non-cleanable. The cleanable mist nozzle refers to a nozzle design that allows the barrel shaped impellar to be removed from the body of the nozzle allowing for the easy removal of foreign debris as well as the ability for cleaning solution to flush the interior of the nozzle and remove any dissolved solids that may plug up the orifice. In 95% of the cases, a poor spraying or plugged nozzle can be dis-assembled and cleaned returning the nozzle to its original performance capability.

The cleanable nozzles also include an anti drip assembly inserted into the body of the nozzle. This assembly prevents the misting nozzle from dripping each time the system is turned off. In some applications this is not that important, but if preventing the nozzle from dripping is important, the anti drip assembly is crucial. The anti drip assembly can be removed from the nozzle if it is not required.

The standard non-cleanable nozzles are less expensive but they cannot be as readily cleaned as the cleanable design. The success rate for improving a plugged or poor spraying non-cleanable nozzle is about 50%. In most cases, the overall investment of the entire misting system justifies the extra cost of the cleanable nozzles. They usually pay for themselves within the first year.

The High Pressure Mist Nozzles page provide specific information on the available misting nozzles, but the additional details below may be helpful in deciding which orifice size is best for a specific application. The .006″/.15mm nozzle (high humidity nozzle) is the smallest standard nozzle orifice available. At 1,000 psi, the mean diameter of the droplets from this size orifice are 12.2μ with droplets ranging from 1.2μ to 36.4μ with a spray diameter of approximately 45 degrees.

• Stainless Steel Nozzle
• Anti-Drip Spring and Ball
• Cleanable Pin
• 10/24 Thread
• .006 // 15mm orifice
• Perfect for humid conditions

The .008″/.20mm nozzle ( humid climate nozzles) is the next smallest standard nozzle orifice available.These premium stainless steel orifice .008 mist nozzles will work with any high pressure mist system that has 10/24 threads (most common size). They also have a removable, cleanable tip that can be cleaned and reinserted. These nozzles are also anti-drip, and come with a spring and rubber ball, which will prevent dripping after the system has been turned off. Requires working pressure of 1000 psi to open anti drip spring. Features and Benefits Works only with high pressure misting systems anti-drip valve built in to each nozzle. Nickel Plated Brass and Stainless Steel construction .008 inch (.2 mm) stainless steel orifice allows for super fine water misting Attaches to any 10/24 threaded outdoor mist cooling system System. Needs to have 1000 psi in order to work properly. These work great in Humid and Semi Humid Conditions.

The .012″/.30mm nozzle (Low Humidity/Dry Climates)  is the medium sized standard nozzle orifice. At 1,000 psi, the mean diameter of the droplets from this size orifice are 13.1μ with droplets ranging from 1.6μ to 39.1μ with a spray diameter of between 65 degrees and 75 degrees. The .012″/.30mm misting nozzle is ideal for applications requiring moderate flow with small droplet size. It has a similar performance to the .008″/.20mm orifice nozzle with an increased flow rate. It is most commonly used for outdoor cooling odor/dust control applications.