How Ultrasonic Technology Can Improve Your Preventive Maintenance
Updated: May 23
It's important to have a preventive maintenance system in place at your company to be able to limit the amount of downtime of your machinery. A great way to do this is with Ultrasonic Testing. This technology is able to read the life cycles of bearings, test for air or steam trap leaks, and even check for arcing on your electrical panels. This form of testing is not greatly known yet so we wanted to provide some information on what the technology is and how to use it. In this blog we will cover:
What is Ultrasonics?
Acousto Ultrasonic(AU) interrogation was first originated by a study from NASA in the 1970s. They were looking for a nondestructive way to examine their bearings and check for hydrogen leaks. In the 1990s, other industries started using this technology in testing their equipment and machinery.
Ultrasonics is the vibrations of frequencies that are greater than the highest level of the audible range for humans (20 kilohertz). Mechanical machinery and equipment can make a large range of sounds from their moving parts. Many of these sounds created are in this ultrasonic range and our not detectible by the human ear.
Equipment for Testing Ultrasonic Frequencies
With ultrasonics being at a frequency that is above what we are able to hear on our own we need to use equipment that makes it accessible to us so we can analyze what is heard. The equipment is able to heterodyne the ultrasonic sounds into audible range for humans and is shown on a display panel.
These instruments use modules to make contact with the item being tested or can scan air born to pick up ultrasonic sounds. Through the digital displays and readings, it provides you can determine the condition or any issues with the item you are testing. In addition to the instrument, there are techniques used and software that can tell you what the frequency readings mean and how it's affecting the item that was tested.
Ultrasonic Testing for Bearings
Downtime at a manufacturing company is always a large concern considering the lost production that it's important to be sure your equipment is functioning properly. A common cause for equipment to break down is the condition of their bearings. There will be another blog that goes into more detail about the importance of bearing testing in the future.
A lot of companies are using vibrational testing when it comes to their bearing analysis. Vibrational is able to give you the life cycle and condition of the bearing, but not as advanced as ultrasonic. For vibrational you are picking up frequencies that are at a lower level caused by the vibrations. With ultrasonics, you are reading frequencies that are beyond what is possible for a human to hear. This allows for earlier detection of damage. Ultrasonic testing can determine if a bearing is failing or bad the first time it's tested without needing a baseline. You can also tell if a bearing is over or under lubed which is one of the main causes of bearing failure. There will also be a future blog about over and under lubing.
Ultrasonic Testing for Electrical
It may be often disregarded as something that can be a large safety issue, but testing your electrical equipment is necessary to be sure that your facility is not at risk. Even the typical way of testing electrical rooms through infrared has a high level of danger, because you have to open the panel doors to test while unaware if there are any issues.
Ultrasonic testing allows you to be able to test for arcing, corona, or tracking before opening up the panel doors. This allows for you to spend less time and money testing your electrical rooms and greatly decreases the risk factor of testing. By scanning the outside of the panel with the proper ultrasonic testing equipment you can pinpoint where in the panel the discharge is located. Then knowing what panels and where in that panel it's located you only have to open those electrical units to make the needed repairs. Ultrasonic testing equipment is able to test electrical panels, transformers, overhead wires, disconnects, and insulators.
Ultrasonic Testing for Air and Steam
When you are looking to make some savings on your energy cost, testing for air and steam leaks is a great option. Air leaks can vary from small to large leaks and steam traps can also vary in size from the size of their leak, but even with small leaks, there is a large amount of cost that is wasted in lost energy.
Around 31% of energy losses can be eluded by fixing air leaks. Ultrasonics can test for air, any type of gas, or a vacuum leak. Common causes for air leaks are vibration, excessive heat, or a bad connection. When testing you can find out what the size of the leak is and what the best option for reacting to that leak may be. You can decide to run at a lower pressure, not use a certain compressor, limit the number of running hours, repair with pipe dope (not tape), or make sure that the pressures are all running at the needed level. There are also formulas that can give you the amount of energy cost you currently have from the air leaks.
If a steam trap fails or is leaking it can cause a safety concern, affect the product being made, and have a large energy cost. Water hammer (high pressure shockwave) can cause significant damage to your equipment and to employees if it's not dealt with. You also want to limit the amount of water sitting in your return lines since that can create rust. It's possible to have energy lost of $10,000 a year from leaking steam traps. That's why it's important to use ultrasonics to test these traps to determine what ones are leaking or failing and to make fixes where it's needed.
Preventive maintenance should be practiced at any company that has a reliance on machinery. The smallest amount of downtime can be avoided by being proactive and testing your equipment to be sure that its functioning properly. Uptime and reliability should be two words that you work towards achieving at your company.
If you would like more information on ways to implement preventive maintenance give our website a look. Also, keep an eye out for future blogs that will go over other topics relating to preventive maintenance and the use of ultrasonic technology.
By Richard E Berg
D.J. Roth Glenn Research Center, Cleveland, Ohio
R.E. Martin and L.M. Harmon Cleveland State University, Cleveland, Ohio
A.L. Gyekenyesi Ohio Aerospace Institute, Brook Park, Ohio
H.E. Kautz Cleveland State University, Cleveland, Ohio