There appears to be a trend happening in industry that needs to be looked at in greater detail and I hope to shed some light on this subject.
We are all so quick to repair the motor, pump, gearbox, or fan when a failure occurs; however, we hardly ever spend time looking at what the equipment is attached to…the base.
Most of these bases were installed years ago when the plant was built and they are aging (Picture 1, above). Then there are the new bases being installed and sometimes they are lighter, or non-grouted, and less rigid. Don’t get me wrong, I am not saying that every problem is caused by the base; however, more often than not it is overlooked initially.
Picture 2 Picture 3
Sometimes we start making the right progress, but end up leaving the base a little short. Look at picture 2 & 3 above and notice a nicely grouted base, but look under the motor…that’s right you can see straight through. Now while this is technically the motor base, for the purpose of this write-up, I consider all of this part of the system base. Why not design the system to look more like Picture 4, the motor mounted directly to a top plate that is anchored in the grout? Again, I know this is not always feasible but do you even consider this design?
Now sometimes even when you think you are doing everything right; problems can still occur and might be hard to see with the visible eye. The use of a Motion Amplification Scan can sometimes enlighten you to problems. The pump base in Video #1 looked fine until viewed with Motion Amplification, now notice the rocking motion. See Video 2 where the left side of the base plate is loose from the rest of the structure. Video 3 is an extreme case, but how many of you have seen something like this in your plant?
Here are some tips to use during equipment outages:
- Inspect the grout for cracks and look to repair if more cracks appear over time or pieces start falling out.
- Make sure the metal has not rusted away and repair/replace if found with serious degradation.
- When grouting the base make sure the grout and the metal substructure actually become one system.
- If the base is or is not filled with grout make sure the metal substructure is properly shimmed.
I hope this has opened your eyes and just maybe you can solve some problems that have been plaguing your plant.
HECO - All Systems Go
About the author:
Jason Spettel is the Predictive Services Manager at HECO - All Systems Go. Jason has over 20 years of experience in implementing and managing predictive maintenance programs (PdM). He has a B.S. in Mechanical Engineering from Michigan State University, is an ISO/ANSI Certified Category III Vibration Analyst, Level I Thermal/Infrared Thermographer, and an ICML Level II Machine Lubricant Analyst.