Note on Raised “Noise Floor”

In a spectrum, if the entire noise floor is raised, it is possible that we have a situation of extreme bearing wear.

If the noise is biased towards the higher frequencies in the spectrum then we may have process or flow problem like possible cavitation, which may be further confirmed by high acceleration measurement (or filtered acceleration measurement) on the pump body on the delivery side (since high frequency waves are always localized).

Smaller “humps” may be due to resonance (possibly excited by anti-friction bearing damage, cavitation, looseness, rubs or impacts) or closely spaced sidebands arising from other defects. A high resolution measurement (or graphical zoom and a log scale) may reveal whether the source is problems that exhibit sidebands or a problem of resonance. If  machine speed can be changed, (for e.g.motor connected to VFD drives) the resonant frequency would not move – but the other peaks would. Sidebands will typically be symmetrical around a dominant peak – e.g. 1X, 2X, 2x LF (100 or 120 Hz) etc indicating different faults.

Interestingly, the time waveform would reveal the reason as to why the noise floor has been raised.

We would see signs of looseness, severe bearing wear, rubs, and other sources of impacts in the time waveform. We must make sure that there are 5 – 10 seconds of time waveform if we suspect an intermittent rub (e.g. white metal bearings of vertical pumps or loose electrical connection of motor terminals) or if we suspect flow turbulence or cavitation.

If the time waveform looks normal (making sure there is a high Fmax (following Niquist criteria) and we view the waveform in units of acceleration then increase the resolution in the spectrum to 3200 lines or higher in case we are seeing a family of sidebands (like the sidebands we find around gear mesh frequency or rotor bars).

But if a natural frequency is being excited (necessary condition for resonance) then we have to perform a bump/impact test or a run-up/coast down test to confirm the situation.

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Fretting Corrosion

In a plant it so happened that a machine with its shaft and pulley assembly was kept idle for little over three years.

Then one day the engineers decided to run the machine. After two months of running, the pulley came loose on the shaft and started rattling – making just enough noise for the operator to notice it and promptly stop the machine thus averting a nasty accident.
This is a case of fretting corrosion. This happens when things are kept in assembled condition for long without running or components are assembled loosely. The asperities at the contact surface that help to hold two components together are lost; thus loosing the vital grip forcing the components to come loose. This wear process is accelerated in presence of low frequency vibration that usually travel to such joints por assemblies from other running machines. The confirmation of fretting corrosion lies in observing reddish coloured powder in between the closely fitting joint interfaces and assemblies.

The pictures of fretting corrosion as seen in this case are the following:

Ways to manage this failure mode:

1. Take care to assemble correctly

2. Don’t leave a machine idle for a long time.

3. Prevent, as far as possible, low frequency vibrations to travel to a machine.

4. If an idle machine is to be commissioned then take care to inspect the joints and interfaces and replace assemblies as found necessary.

5. May be monitored by Wear Debris Analysis for lubricated joints and interfaces and by vibration monitoring for dry joints and interfaces or simply by visual monitoring.

Observing Complexity

To me, observing real life systems is something like this:

A real life System comprises of a meaningful set of objects, diverse in form, state and function but inter-related through multiple network of interdependencies through mutual feedbacks enclosed by variable space, operating far from its equilibrium conditions not only exchanging energy and matter with its environment but also generating internal entropy to undergo discrete transformation triggered by the Arrow of Time forcing it to behave in a dissipative but self organizing manner to either self destruct itself in a wide variety of ways or create new possibilities in performance and/or behaviour owing to presence of ‘attractors’ and ‘bifurcations’; thereby making it impossible to predict the future behaviour of the system in the long term or trace the previous states of the system with any high degree of accuracy other than express it in terms of probabilities since only the present state of the system might be observable to a certain extent and only a probabilistic understanding may be formulated as to how it has arrived at its present state and what would keep it going, thus triggering creative human responses to manage, maintain and enhance the system conditions, function and purpose and create superior systems of the future for the benefit of the society at large.

Such a representation of an observation looks quite involved. Perhaps it might be stated in a much simpler way. Most real life systems behave in a complex manner creating multitude of problems of performance and failures. But how do we get rid of complexity and uncertainty as exhibited by systems? We may do so by deeply observing the complex behaviour of the system to improve our perception to gain insights about the essence of the system; find out the underlying ‘imperfection’ that causes the apparent complexity and uncertainty and then find ways to improve the existing system or create new system and maintain them in the simplest possible manner. We do this by applying the principles of chaos, reliability and design. Surprisingly, the same process might be used to troubleshoot and solve problems we face on a daily basis. If done, we are no longer dominated or dictated by the ‘special whims’ of the system.

The crux of the matter is how we observe reality and understand it so as to make meaningful choices as responses to life and living.

Expert Knowledge is Passé; Long Live Masters!

Engaging with flow, created by any phenomenon, is an essential step that we take to create something new, which invariably amounts to an interpretation of our environment or surrounding triggered by noticing something from the higher levels of the mind that is less dependent on sensory inputs.

Why is this necessary?

Since our mind is a system consisting of complex networks it has memory like all other networks. Memory would then compel the network (our mind) to behave in very predictable patterns i.e. it would continue to behave the way it does unless the energy of the system is changed by design. It would mean that our response to any situation would stay the same unless we add new energy to our existing network urging it be respond or behave differently.

That is the basic idea of engaging with the flow — to add new energy to our neural network to come up with a different response to a situation we are facing in the moment.

But that is tricky business. Much more tricky than we might care to imagine. It is because we must notice in quick succession (almost as quick as clearly noticing a ten digit telephone number) for our neurons to get energized enough to rise above their critical threshold limit to create harmonious oscillations, helping us to create new knowledge and response. Fortunately, our neurons, under this situation of noticing different aspects of a phenomenon in quick succession, produce different frequencies from moment to moment, which helps to create new responses. However, to produce useful and new harmonious frequencies our mind also needs to be supported by a healthy relaxation oscillations. Relaxation oscillations help us absorb new learning. Relaxation oscillation in the brain is something like this — neurons slowly absorb energy and then quickly release the energy. This new release of energy helps neurons to jump over their critical threshold limit to create harmonious oscillations.

Let us understand this process by some live examples.

For example, Sachin Tendulkar is considered the ‘god’ of cricket. For him, captains and bowlers of rival teams have a hard time setting a field to hold him down. He always tends to find the gaps too easily against any type of bowling. It is easy to imagine that he is quickly noticing so many aspects of the phenomenon — the bowler, his run up and stance, his delivery, speed of the ball, trajectory of the ball, movement of fielders, etc in quick succession (really quick since the ball is traveling at a speed of nearly 100 km/hour). Within that time he decides where and how to place the ball to get runs, which is invariably between the gaps in the fielding.

Or take Ravi Shankar, the great musician, who plays so intuitively. To me intuition is nothing but the same process as described above, where new harmonic oscillations are produced with the help of relaxation oscillations.

Or say Michel Angelo who saw entrapped figures trapped in uncut stones waiting to be freed by his hands.

There is one thing that is common to all of them which sets them apart from the rest. They all intuitively find the gaps or the existing imperfections in the present moment with their uninhabited awareness to reach their goal. This is because all human minds by default are goal oriented since human consciousness is more temporal than spatial. They improvise their games based on those gaps or existing imperfections in the most intuitive way — no copy book styles for them. They have learned the rules of their games so well that they now break them with impunity by mastering the way to trigger relaxation oscillations at will. This process of engagement is played over and over in whatever game masters choose to play. Games differ but the process of engagement does not.

This is what innovation, improvisation, improvement, creating new knowledge is all about.

The Japanese have a name for it. They call it Wabi -Sabi, which means understand the imperfection in a given situation and improve upon it to make it stronger and more reliable.

The Chinese have a name for it. They call it Shan Zhai, which originally means balancing numerous resistances, see what is possible to be done cheap and effectively, start small and then grow in strength.

The Indians have a name for it. They call it Juggad, which means understand what is to be done, start with whatever is available at hand, go with the flow and build up over time.

How would this be useful in present times?

Today, expert knowledge (essentially a knowledge bank) is sold in the market as a commodity that is continually being sold at lesser and lesser price wiping out premiums that they once commanded. It is so since expert knowledge is increasingly being converted to cheap ordinary stuff through algorithms. In some fields of human activity the value of expert knowledge is almost zero — given freely over the internet. Then how are we to survive in the present situation. It definitely calls for a new skill – the skill of mastery, where new knowledge can be created moment to moment. This amounts to present moment responses to a changing situation. People who can really do that are priceless and can still command a premium in today’s market place.

Such skill of mastery basically calls us to be in touch with one’s essential nature. Gregory Bateson reminds us of this fact when he said, “When man lost touch with nature, he lost touch with himself.” Simply stated, “losing touch with himself” is disengagement – a phenomenon that is so common in our professional world.

This is the only way to create a good sustainable future for all since, “The future is never empty, never a blank space to be filled with the output of human activity. It is already colonized by what the past and present have sent to it.” (Fry 1999)

How do we develop that is the question? Understanding that involves deep learning. And deep learning is done by power of engaging with the flow of the moment.

State a Problem in Simplest Terms

The other day, a long-term client of mine called me up to see a problem of theirs. Since it is a public sector organization they soon sent me a RFP (request for proposal) over email with a fairly detailed SOW (Scope of Work).

In the SOW, they mentioned all that needs to be done, almost breaking down each step. In short, they were proposing a detailed method to solve their problem.

When they followed me up over phone, I said, “With such a detailed methodology in place, why would you ever need me?”

Sensing that they did not get it, I elaborated, “Does it mean if you just have the results of those steps that you have listed out you get to the answer you are looking for? Do you think that such detailed investigations, which you have already carried out earlier, would inflate costs without getting anywhere close to the solution?”

Fortunately, they quickly realized the gap. They asked me, “What should we do then?”

I replied, “State your problem in its most basic and simplest terms. Complex, nagging problems can’t be neatly defined. Instead, you could just state your concern about the problem. That would trigger our collective minds to flow easily to reach a solution. For example, you could state that you are suffering from a headache every evening.”

“O.K.” they said, “Our issue is that we are responding as per prescribed textbook rules to solve this problem and the problem seems to be temporarily fixed but it resurfaces after some time.”

“Just state that. And then we follow the cues to get to a working hypothesis, a working methodology to test out the hypothesis, collect data, arrange and interpret the data, collectively understand the issue with the simplest theories that fit the facts of the problem, formulate practical actions, carry out those to test our hypothesis and learn more to eliminate the problem for good.”

In the next fifteen minutes they sent the revised RFP, stating their concern.

By stating a problem in its basic and simplest terms we allow our minds to pay attention to flow effortlessly towards a solution.

That is what is needed when we tackle complex problems – problems for which answers are not available in the books or can’t be googled.