Gaurav - Thank you for your kind comments. I do not have a training tutorial on mechanical seals or packing per se but I will develop one if there are more interested people such as yourself. Thank you for watching the video! John Piotrowski

The explanation for why the vibration decreases is explained in slide 16 in the tutorial. Here is the text for the narration of that slide ... If you remember, a short while ago, when we were talking about things that put static loads on bearings, it was mentioned that three very common sources of static forces on bearings were gravity, or the weight of the rotor, belt tension, and shaft misalignment. So, let’s examine the static forces that are present in these two shafts and for this discussion we are viewing the shafts in the side view. The shaft on the left has some weight so there is a downward force on it due to gravity. Each bearing produces an upward force opposing the gravitational load. Similarly, the shaft on the right sees the gravitational force and its bearing produce an upward force to oppose the gravitational load on them. If we begin to misalign these two shafts, the flexible coupling accommodates a certain amount of the misalignment but once that is exceeded the shafts will start elastically bending. The gravitation forces are still there but now, through the coupling, the shaft on the right induces a downward force on the shaft on the left. This force now produces an additional force on the inboard bearing in the downward direction but it will produce an upward force at the outboard bearing. The shaft on the left produces forces on the shaft on the right also. Through the coupling, the shaft on the left induces an upward force on the shaft on the right. This force now produces an additional force on the inboard bearing in the upward direction but it will produce an downward force at the outboard bearing. If we continue to misalign these two shafts, the shaft begin elastically bending even more. The gravitational loads are still present, across the coupling, the downward force on the end of the left shaft has increased as well as the reactionary forces on its bearings and the upward force on the shaft on the right has increased as well as the reactionary forces on its bearings. Shaft misalignment induces static forces on the shafts that will diminish the amount of motion / vibration that is occurring.

Ashish - Sorry for the delay in getting back to you. When forced to run under shaft misalignment conditions, different flexible coupling designs do different things depending on the design of the coupling. It has also been observed that different vibration spectral patterns occur with different types of flexible couplings. I have another training tutorial on this subject in the ADVANCED shaft alignment training videos that I have not published yet. This information however is in Chapter 2 of the 3rd edition of the Shaft Alignment Handbook (ISBN# 978-1-57444-721-7). I hope this has helped you. Thanks for watching the video! John Piotrowski

Faith - Sorry for the delay in getting back to you. My email can be found on our web site www.turvac.com. I will help you as much as I can. Thanks for watching the video! John Piotrowski

Sushil - Indeed. Many people are shocked what actually happens to the vibration on misaligned running machinery. Thank you for watching! John Piotrowski

Sushil - Indeed my friend. Many people are surprised concerning this phenomena. I think the reason there is confusion about this is that very few people have ever explained that static forces are occurring in a misalignment condition which will diminish the capacity for the machinery to vibrate freely. When I intentionally misaligned a drive system for the first time, I fully expected the vibration to increase.... and it did NOT. It took me over two years to figure out what was really happening and WHY the vibration went down when I misaligned a drive system. It took me another two years to have the courage to say something about this and explain how this could happen. I still think that the vast majority of people who work on rotating machinery believe that vibration will increase when you misalign machinery and I don't think I'm going to live long enough to explain why it doesn't. So I'm hoping you will help me with this. Thank you - John Piotrowski