September 7, 2017
By Tom Shelton
Whether instructing a training class for precision shaft alignment or geometric measurements, the topic of machine specifications frequently comes up. Specifications such as shaft alignment tolerances, bolt torque values, frame or base flatness requirements and the frequency of verification of these specifications are typical of what is asked.
There are general industry specifications such as bolt torque that can be applied, but are these correct for all equipment? Are all shaft alignments acceptable when in “industry standards”? What about the machines that require special treatment?
During a recent Fixturlaser NXA Ultimate Shaft Alignment Best Practices and Geometric class, at a gas compression site, the very question of “What specs do we use?” came up. In this case, general industry standards did not apply. For whatever reason, be it metal composition, manufacturing tolerances, etc. other than general specifications were required. Failure to meet these specifications has the potential of catastrophic failure. At a gas compression site this could be conceivably disastrous!
There are ways of finding out if you need modified engineering specifications or if general industry standards are acceptable to properly set up and maintain the reliability of a machine. Ask the manufacturer or Google it! Another possibility is to go to the App store (Android or Apple) and type in the search bar to see what is there. A member of the class knew of an app by Ariel Corp., so we all downloaded it.
Upon further searching, I was amazed at how many apps are available relating to gas compression alone. For instance, the Ariel Corporation App is designed specifically for their reciprocating gas compressors. The app has Ariel’s required bolt torque specification for each fastener used on their compressors.
Also, Ariel has a Soft Foot and Flatness Specification (ER-82) for certain model compressors. VibrAlign has worked with Ariel to approve use of the NXA Ultimate in conjunction with their ER-82 Worksheet, to minimize the amount of work required when checking and correcting the compressor frame flatness, to meet their ER-82 Specification. It is safe to assume that any other required engineering specifications for their compressors would be readily available through Ariel Corp.
So, do yourself a favor and look at the Apps that may be available specific to your industry/machinery. Contact your OEMs with questions about proper maintenance requirements for the machines they manufactured for your facility.
Times change and so do best operating and maintenance practices. One can’t expect the manufacturers to reach out to every individual that may work on their machines, so it is up to you.
Also, don’t forget about the free VibrAlign Apps. Google it or go to your respective app store or go to https://acoem.us/tools/mobile-apps/.