Last year I worked with a power company that was having issues with Position Feedback Sensors overheating causing erroneous readings and early failures. The sensors were located above a steam turbine, and the ambient temperatures reached 128°F with spikes to 140-150°F. The customer had called in looking for a way to keep the sensors cool, using minimal compressed air, and in a robust package. After reviewing the details, we recommended the High Temperature Vortex Tube, model HT3210. While using just 10 SCFM of 100 PSIG compressed air, the HT3210 provides 8 SCFM of cold air at a temperature drop of 54°F from the supply air temperature. Bathing the sensor with this cool air keeps prevents it from heating up and has eliminated the bad readings and prevented the early failures.
The customer recently implemented the same fix for another set of sensors.
The High Temperature Vortex Tube is a special Vortex Tube offering from EXAIR that utilizes a brass generator and hi-temp seal for use in ambient temperatures up to 200°F. Simply supply clean, dry compressed air, and get cold air starting at 50-54°F lower than the supply air temperature. With sizes ranging from 2 to 150 SCFM, there is a Vortex Tube that will meet most applications.
If you have questions about the Vortex Tubes, or would like to talk about any of the EXAIR Intelligent Compressed Air® Products, feel free to contact EXAIR and myself or one of our Application Engineers can help you determine the best solution.
What can you do when the pneumatic positioner in your high temperature application is overheating? Call EXAIR!
Or email (and call), as was the case in this application. An end user in an overseas power plant uses a pneumatic positioner in their steam bypass system. A pneumatic positioner can best be correlated to a PWM (Pulse Width Modulated) linear actuator. It will take a supply signal of various forms and provide an output to an actuator or valve, most often to regulate pressure/flow. So, why not just use a pressure regulator? Because a pneumatic positoner can be programmed to respond differently to different inputs, and it can function in real time. Meaning, that when the supply signal reaches a certain threshold the output action can be preset, adding precision to a pneumatically controlled application. And, as application needs change, the adjustments can be automated.
Some pneumatic positioners are pneumatically controlled (the input signal is a compressed air pressure), but most are electronic. The end user in this case was using an electrically controlled unit that was experiencing shutdown due to the high ambient temperatures.
When cooling in an application like this it is important to consider the needs (and restrictions) of the application. To blow ambient air was not an option because of the high ambient temperature, so a Super Air Amplifier, Super Air Knife, or Super Air Nozzle weren’t viable options. And, the pneumatic positioner was exposed to ambient conditions, with no intent to place within an enclosure.
The lack of an enclosure ruled out a Cabinet Cooler, but a Vortex Tube based solution was still possible. When considering the heat load and required cooling capacity, the end user determined that with less than 200 BTU/hr. of cooling, the application should run flawlessly. This customer also expressed they may have fluctuations in there pressure supply, and ambient temperatures which would create the need to provide a larger Btu/Hr Vortex Tube in order toake up for lower pressures and increased temperatures. Our smallest Vortex Tube is capable of producing 550 Btu/Hr and was recommended for a successful application.
If you have an application problem in need of compressed air solutions, call an EXAIR Application Engineer.
As I scanned through my emails this morning in search for a Cabinet Cooler Sizing Guide sent to me back in June (some changes were made by the end user and I wanted to reference the original heat load), I noticed the large number of sizing requests typical of summer months. When I clicked back to my inbox I saw four more Cabinet Cooler sizing requests awaiting me from different corners of the globe.
One that stood out to me was in a particularly hot environment (Approximately 180 degrees Fahrenheit), and needed NEMA 4X protection. The end user was kind enough to send a sketch of the enclosure they plan to use, and needed to know if an EXAIR NEMA 4X Cabinet Cooler could work for their application.
Fortunately for the end user, our Cabinet Coolers are suitable for many types of enclosures, and we have a staff of Application Engineers on hand to sort through any abnormalities or questions which may arise. So, we are able to say with certainty that our Cabinet Cooler can work in their application.
Another fortunate feature for this end user is that EXAIR manufactures High Temperature Cabinet Coolers available from stock, and suitable for temperatures up to 200 degrees F. These high temp systems are perfect for metallurgical plants, use near ovens or furnaces, and for applications with higher than normal compressed air temperature.
If the specifics of your application raise any doubt about integrating an EXAIR Cabinet Cooler, contact an EXAIR Application Engineer.
The five C’s of EXAIR products are Cooling, Cleaning, Conserving, Conveying, and Coating. All EXAIR products are suitable for applications in these areas, with varying degree of possibility. When it comes to cooling, one of the most suitable EXAIR products is the Super Air Amplifier.
An Air Amplifier can increase the volume of ambient air directed over an specific area, effectively decreasing the cooling time needed in an application. Air Amplifiers cool effectively due to the fundamental principles of convective heat transfer. In convective heat transfer, cooling capacity can be increased by increasing the temperature differential between the cooling medium and the object to be cooled, or by increasing the flow of the cooling medium.
An Air Amplifier is the best cooling choice when the material to be cooled is at an extremely high temperature. For example, in the application above, 903°C (1650°F) cylinders need to be cooled to ambient temperature as quickly as possible. Vortex Tubes are another product our customers consider for cooling applications. Vortex Tubes are the best choice when the area to be cooled is small and the temperature differential is not as large. A Vortex Tube based solution will provide very cold air, but at a lower air flow over a small area and they were not the best choice for the application in the image above.
In the same application, a Super Air Amplifier can provide large volumes of ambient air over a large area, effectively cooling the cylinders much more efficiently. The cooling can be achieved in less time, and with maximum efficiency of compressed air implementation. Air Amplifiers also offer great benefits over electric fans in this rough environment: they can withstand higher temperatures and there are no moving parts to wear or break.
If you have an application in need of efficient cooling, contact an EXAIR Application Engineer to find out if an Air Amplifier will work for you.