Want to learn more about EXAIR’s line of Atomizing Spray Nozzles? This short video will familiarize you with their benefits, features, and capabilities.
If you follow along with our blog, you will notice that we have recently published a few entries relating to our Atomizing Nozzles. Today, I would like to continue this trend and focus on our Siphon Fed Atomizing Nozzles.
When recommending an Atomizing Nozzle for a particular process, we try to obtain as much “general” information as possible about the application, such as:
- What type of spray pattern do you need?
- How wide of an area needs to be covered?
- What kind of flow rate needs to be achieved?
- Is the liquid source pressurized?
- What is the viscosity of the liquid?
While all of this information is going to help simplify the selection process, when we get a reply that the liquid isn’t pressurized, the choice becomes a little less complicated.
Our Siphon Fed Atomizing Nozzles are the preferred solution in applications where a pressurized liquid source isn’t available. With a steady supply of compressed air, these nozzles are able to draw the liquid into the nozzle with suction heights up to 36″ for our 1/8″ NPT and 1/4″ NPT nozzles, and up to 24″ for our larger 1/2″ NPT Models. They can also be gravity fed as well.
These nozzles mix the fluid internally and are capable of handling viscosity up to 200 centipoise. Depending on the size of the nozzle and supply air pressure, flow rates can range from 0.4 GPH up to 60 GPH with either a round or flat fan spray pattern. There is also an adjusting valve for more or less liquid flow as needed to fit the demand of the application.
We also offer these nozzles with our patented No Drip feature which positively stops the liquid flow when the supply air pressure drops below 30 PSIG, eliminating the need for any additional valves or supply lines.
If you have an application requiring a fine mist of atomized liquid, give me a call at 800-903-9247.
EXAIR has been manufacturing Intelligent Compressed Air Products since 1983. We work every day with air properties, such as compressed air pressures and flow rates, when evaluating product performance to provide a solution to a customer problem. We also need to be versed on a certain liquid property, viscosity, as it relates to the operation of (2) of the EXAIR product families, the Atomizing Spray Nozzles and the Industrial Housekeeping liquid vacuums (Reversible Drum Vac and Chip Trapper).
Viscosity is often referred to the thickness of a fluid. A common example would be water and honey. Water is a low viscosity fluid, while honey is a high viscosity material.
Dynamic, Shear, or Absolute Viscosity is a measure of the resistance to shearing flow. If you think of 2 plates (see below) with the bottom one stationary and the top one moving horizontally, and with a fluid between them – this illustrates Absolute Viscosity. When the top plate moves to the right, there will be induced multiple horizontal layers of the fluid, each moving at different speeds (the fluid will be at rest at the bottom, and the top layer will move with the top plate.) The friction generated between the layers will give rise to a force resisting this motion. The force is proportional to the speed and area of the plate and inversely proportional to the distance between the plates.
In simplest terms, viscosity is the ratio of the shear stress, τ, to the velocity gradient du/dy. Of concern to us, it takes more force to cause a very viscous (thick like honey) fluid flow.
Centipoise, cP, is the common unit of measure for viscosity, and 1 cP is equal to 0.01 g/cm/s.
Water has a viscosity of 1 cP at room temperature and honey ranges from 2,000-10,000 cP.
How does all this relate to EXAIR? It relates to EXAIR because we engineer products to specifically move and use liquids. There are limitations to the viscosity each of these products can handle and still perform well.
The EXAIR Atomizing Spray Nozzles can be used with liquids up to 800 cP. The Internal Mix type nozzles can be used on liquids up to 300 cP. The External Mix nozzles can be used with liquids over 300 cP and up to 800 cP. Lastly, the Siphon Fed models are good to 200 cP, and do not require a pressure source for the liquid. Each nozzle type will atomize the fluid and provide a very small droplet size, which is ideal for washing, rinsing, coating, cooling and other applications. Exceeding the cP each of these nozzles are designed to use will result in larger droplet sizes and a more inconsistent fluid flow, which may impact your process.
The other EXAIR product family where viscosity is important, is the Industrial Housekeeping Products, especially the High Lift Reversible Drum Vac and High Lift Chip Trapper. They are capable of moving liquids with viscosities of up to 1400 cP through 20′ of hose. Simply provide compressed air and turn any closed head drum into a high powered liquid vacuum. Great for coolant, hydraulic oils, waster water, and many other fluids. For these products, as the cP increases, so does the time it will take to move the liquids into or out of the drum.
To discuss your fluid viscosity and how an EXAIR Intelligent Compressed Air Product can make your process better, feel free to contact EXAIR and myself or one of our other Application Engineers can help you determine the best solution.
The other day, I had the pleasure of helping a caller select an Atomizing Spray Nozzle for a particular application. They needed to apply a thin, quick drying coat of vanishing oil to the inside diameter of a round, deep drawn metal part. They were currently flooding the ID with it, and the part had to sit overnight to dry.
Since it was a cylindrical hole, it sounded like an ideal application for a Round Pattern nozzle, and, since they didn’t have an easy way to pressurize the oil source, we selected a Model SR2040SS No-Drip Siphon Fed Round Pattern Atomizing Spray Nozzle. By adjusting the siphon height and air pressure applied, they were able to quickly achieve the desired flow pattern and coating thickness.
Now, they’re able to take the part directly to the next step in their fabrication process, without the overnight drying cycle.
(800)923-9247 toll free