Categories: Shaft Alignment

Understanding Alignment Target Data from the VibrAlign ThermAlign App

| | |

By on May 13, 2015

Dynamic Movement, often thought of as thermal growth, is a hot topic among alignment professionals (I’ll be here all week!). Plant Services Magazine in conjunction with VibrAlign recently hosted a webinar on this subject (details below).

One of the more popular ways to compensate for thermal growth is through the use of a thermal growth calculator. The calculator calculates growth changes that occur from measured temperature changes on the machine. VibrAlign released a free app, ThermAlign, that performs the calculations from measured data.

Modern laser shaft alignment tools allow the user to input target values prior to doing the alignment. Growth is the actual movement due to temperature changes and targets are the compensation for that growth. The ThermAlign app takes the growth values and converts them to target values at the feet of the moveable machine. The target values can be input into the laser system prior to performing the alignment. Here is an example from real data taken in the field. In this example the customer took temperature readings on the blower at the feet and at the shaft centerline. The motor wasn’t measured since his experience proved the temperature changes were minimal.

photo-220

To find out more about Thermal Growth and OL2R checkout the “On Demand” Webinar hosted by VibrAlign’s Stan Riddle and Mike Keohane, entitled “Hot Alignment & Thermal Growth.” The Webinar steps through 4 ways to deal with thermal growth target values when performing a shaft alignment!

1. Inputting thermal growth targets as provided by the engineering department,
2. Using a Hot Check to measure the thermal growth and set targets,
3. Using the free ThermAlign app to calculate the thermal growth targets, and finally
4. Measuring the thermal growth, as well as dynamic changes in machinery, using OL2R software and
fixtures. (OL2R, by the way, stands for Offline to Running)

To see the recorded “On Demand” version of the webinar please visit our sponsoring partner, Plant Services [HERE]. Click the “On Demand” tab and scroll to the bottom of the list of webinars and you will see “Hot Alignment & Thermal Growth.” Click Login. You will need to set up a login to view the webinar, which lasts about an hour including questions and answers.

Additional Blog Posts on the subject of dynamic movement.
http://thealignmentblog.com/blog/category/alignment-troubleshooting/dynamic-movement/

 

About the Author

Mike Keohane has been involved in machinery reliability since 1985. He started as a field service engineer for IRD Mechanalysis. Prior to that he was a wireline logger for Schlumberger Well Services. He joined VibrAlign in 1992 and supports clients in Georgia, South Carolina, Alabama and the Florida Panhandle. In addition to precision alignment, he has field experience in vibration analysis, field and shop balancing, oil analysis and ultrasonics. Mike holds a BSME from Michigan State University. Mike and his wife and two children currently live in Peachtree City, GA.

One response to “Understanding Alignment Target Data from the VibrAlign ThermAlign App”

  1. Mac says:

    Informative article Mike! Well written.

Leave a Reply

Your email address will not be published. Required fields are marked *