Root Cause Analysis


Root Cause Analysis is one of the method of finding out cause to a problem occurring in industrial as well as any incidents or any investigation related to breakdowns, shutdown, crimes and accidents. It is a method in which the analysis of an incident is carried out by analysing the sequence of events which lead to final outcome. This includes a procedure like PDCA or 6 why (6?) evaluation. The PDCA method involves the following 4 steps

P- Problem identifying

D- Data collection to support the cause for the problem identified

C- Finding out the cause for the cause

A- Taking appropriate action so that the same event may not occur again


6? Six why method in which you ask 6 times  why the problem had occurred to find out the cause for the problem and taking appropriate action by eliminating the cause in any of the 6 steps in 6? method

Let me elaborate by giving an example

A control valve is fretting or hunting due to which a unit process is distributed or shutdown

Here simply you ask 6? for P, that is problem identifying

1? (first why) Why the cv is hunting/fretting?


     1. Loose link due to vibration

  1. 2.fluctuating FT in loop

    3. positioner problem

4.vibration in the line causing the trim plug to disturb

Now if you correct FT, positioner, link, there will be still vibrations in trim

2? Now find second why .Here you ask why the plug and stem and seat is experiencing vibration?


     1.Due to aging of trim set

  1. 2.Under rated control valve

    3.Principles and type of control valve

    4.Not proper bench setting of control valve

    5.Corrosion of the stem

    6.Choking of the cages resulting in high DP which resists proper operation of control valve

    7.Turbulence and hitting of the steam flow causing the stem to vibrate abruptly or turbulence due to 90 degree IP valve due to throttling effect.

Now if you correct the problems like aging by replacing, increasing the rating of control valve, changing the plug type to ball or other types or vice versa, bench setting the cv, removing the corrosion and choking of cv ; there will be still a major problem which is the turbulence of steam which is causing the stem-plug-seat to vibrate

Now3? (third why)

Now ask the third why…why is there turbulence in the steam flow?

Steam by virtue will be having turbulence but can be reduced to a considerable amount. The turbulence may be due to

  1. 1.Water content or condensate in steam causing to hunt

    2.High temperature or varying temperature of the steam because of faulty temperature transmitter in the loop

    3.A faulty steam governor

    4.A faulty vibrating pump which is used to distribute steam

    5.Improper piping designs causing high DP and steam turbulence

Even if we correct problems like condensate reduction by filtering out condensate using pot, rectifying TT and steam governor, improper piping designs

There will be turbulence in the steam due to pump which is discharging the steam.

Now 4? (fourth why)

Why is the pump discharging the steam is faulty or found to be vibrating abnormally

  1. 1.Because of improper installation of pump

    2.Not using proper material for maintenance OEM parts

    3.A faulty vibration monitoring system

    4.Improper alignment and gear box wear and tear

    5.Aging of pumps

    6.Deformation of pump parts due to high steam temperature

    7.Improper lubrication or maintenance

    8.Environmental or Climatic conditions of the area of installation of the pump like congestion, high/low temperature condition, proximity of installation of multiple pumps

    9.Varying/ unstable electric current (amps) of pump

    10.Varying/ non uniform steam coming out from STG

And many more………

Even if we rectify problems like improper installation by rehabilitation, standard material for worn out parts, correcting proper vibrating monitoring system, by maintaining steam temperature at a constant level, electrical maintenance ; there will be a major problem of lack of maintenance of pump/electric relays/instrumentation and mechanical machines and instruments.

Now comes 5? (fifth why)

Why there is improper maintenance of machines, instruments and electric devices

Answer is:

  1. 1.Lack of proper maintenance knowledge of manpower (who should do the specific jobs)

    2.Improper materials used for maintenance

    3.Improper manpower allocation

    4.Lack of field managerial skills

    5.Lack of technical trainings

    6.Improper management of time (rushing and hustling) for a critical job

    7.Improper planning of planning engineers

    8.Sub contractor system which creates ego between top management and workers is a sin to a work environment. Dejected employees, depressed employees, unmotivated employees, desolate employees are very harmful to any organisation;

And many more other reasons….

Even if we correct the problems by using proper standard materials, proper man power allocation, proper trainings, and proper planning

There will be still problems of managerial skills.

Now comes the conclusive 6? (sixth why)


Why lack of managerial skills?

Managerial skills play a vital role in analysing the main root of the problem this is due to following reasons

  1. 1.Cost cutting – most of the inefficient managers believe that cutting or reducing the salary of employees will give profit to company. This is not true, talented employees are resources to a company 

    2.Stupid company owners.

  Most of the company owners are just a     puppet or a benami whom are just order   executive for a foreign criminal owner   or organization whose managerial skills   are very feeble

  1. 3.Improper and uneven increments and rewards’. Divide and rule will eventually collapse an empire. Example is the United Kingdom. Proper increments and rewards are very necessary for every employee depending on their performance and not on nepotism, recommendations, relationship (nephew-niece-uncle) and back door appointments’

    4.Most of the mangers not even know what is the field conditions, they simply analyze what is on their table; feeling the beat of every problem from the perspective of field side is very essential. I didn’t mean that they should come to field and work using tools but field conditions are very much relevant

Whatever is the best and excellent managers do, the employees follow. He is then called a leader, a captain, a manager…….

Let me conclude,

Root cause analysis is basically an analysis of events or effects which has occurred due to some or multiple causes. Basically it is a “cause effect” principle.

It is a conventional method to find out why a problem has occurred due to some reasons.

In order to eliminate the problem from occurring you should cut the main root which is the main reason for problem not the unnecessary roots which can be done by continuous monitoring of abnormal behaviour of system

Then what is the best solution.

“Quality not the quantity”

Choose wisdom rather than choosing a large manpower

The main cause explained for the above problem is turbulence of steam; any modifications which will convert a turbulence to a linear flow( a flow straightener) will work including a piping arrangement/ design which will reduce condensate or water in steam which causes turbulence, a P.R.V pressure reducing valve which will allow the abnormal increase in pressure to pop up and releases the unwanted pressure, changing the plug type valve to ball valve (or some plug-trim set ,head modification),addition of grooves , increasing the rating of control valve, increasing the plug seat stem size (trim size), proper and periodic maintenance of electric  and instrument devices and pumps using O.E.M parts, removing aged/wornout machines and devices, proper monitoring of instrumentation in the system.

“And the most important never judge any problem with past experiences, before it had happened; so now the reason will be the same”

Simply replacing the link with strong link made of gold, silver, platinum or diamond will not work, as it is the effect not the cause. Eliminating or reducing the effect (fretting, hunting) will not work, you have to cut the root (in this case turbulence due to vibrating pump and turbulence created in the trim set when not fully opened) of the problem….that is called root cause analysis….During analysis you will encountering many small irrelevant misleading roots but the cancerous main root should be identified, cut and thrown out. Only talented engineers are capable of doing that.

Proper periodic technical trainings (I mean trainings not technical presentations), examinations and tests for all employees including managers are required based upon which promotions and increments are to be provided.

Manpower management should  be done properly; doesn’t mean that in 8 hours an employee should give a progress report for full 8 hours without rest; only  stupid manager will think like that. Right man for right job is what we call management.

Unnecessary PM jobs should be replaced with of that predictive maintenance.

My special thanks to sir Mr. Ajit Vadakayil, my mentor and teacher whom I have never met.

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