Six Sigma: It is the Approach that Matters
BY PARMINDER SINGH
When we talk about six sigma; black belt, green belt etc. and spend so much money on training, implementation, correction and investment, often at the end of the day it is futile. The reason is simple, before going for six sigma your approach and attitude towards machine, material, manpower and processes should be six sigma, else whatever you do will not bear any fruits. Even after spending so much money on six sigma training we are not able to sustain it for long or always find difficulty in convincing employees, managers, company that it is not an obstruction.
Example: Signal light at traffic intersection when goes red it means stop, whether there is no traffic or you are on remote area or it is late night it does not matter red light means stop. If you have that attitude, then it means you are fit for sigma.
What are the hurdles in achieving six sigma quality one and the foremost is knowledge of process, material, machines and attitude? Let us suppose you are working on one machine you have to understand all the possible variables in the machine whether it is machine parameters, material parameters, environmental parameters in deep detail not everyone but at least the head of the unit and two or three persons down the line. Deep understanding, means deep understanding let me explain you with one simple example.
Hardening all of us has studied in engineering about it, that when metal is heated and it becomes red hot and instead of cooling slowly back to its temperature if we quench it in cold bath metal become hardened and brittle in composition. So how it is related to electronics industry yes, it is, solder joint when heated in reflow oven and if the cooling of solder joint is instant then joint becomes brittle which cannot be detected by naked eye or any AOI (Automated optical inspection) machine in the world consequences are that it passes all the test and material is shipped to the customer. And during transportation or mishandling joints break and customer will suffer in end. So, you explain hardening process just saying that cooling should be slow and gradual else joint will be brittle does not solve the process problem what is the deep theory behind it.
If we do not do proper maintenance as per the manufacturer guidelines results will change and result will be catastrophic one day.
Every material is made up of either electrovalent or covalent bond at “X” distance apart, when we heat the metal we supply energy to its atoms and they start moving apart and as we raise the temperature joint becomes weaker and weaker or the bond between them become unstable. Now to bring it back to it is original state you should bring it back to room temperature slowly, but now if you dip it in cold water they will not come back to its original position they will be at X + n distance from its normal position which is an unstable state and that is why it becomes brittle. See figure above.
What I am trying to emphasis here that process head of any company in the world should have such a deep knowledge about the material this is only one example I have quoted. We have so many other variables let us take an example of machines
Machine are designed for certain defined capabilities there are many parameters in the machine which are designed using certain datum or say reference point w.r.t. that all other parts are fitted. As we use the machine due to wear and tear this datum shifts with time. So to keep the datum intact there are recommendations from manufacturers which needs to be followed strictly like, calibrations and maintenance of the machines with recommended consumables for the same. Reason is simple everything changes with time whether it is man, machine or material. This process is very slow and to catch the changes becomes difficult. If we do not calibrate and do proper maintenance of the machine as per the manufacturer guidelines results will change and result will be catastrophic one day. Let us say manufacturer recommends grease for your machine of certain grade and one particular manufacturer only and your process engineer finds grease which is cheap and started using it you do not know the results of that may be the particle size of the grease is much bigger than it is recommended by manufacturer and it destroy the sliding part of the machine or temperature withstanding capacity of the grease is too low and you use it for 24 hours nonstop and it loses its property and in parallel you loses your machine.
What I am trying to emphasis is that we live in society and everyone has its own responsibilities like, milkman, sweeper, newspaper man, driver we cannot do everyone work similarly machine, material, component manufacturers have also done some years of research before coming out with design with so many different parameters do not try to undo their work just follow what is being defined by them as per their specifications and recommendations.
If manufacturer defines, this should be the pressure, temperature, speed, environment temperature mixing ratio, viscosity, tackiness with playable window for each just do it, do not go beyond that, record it monitor it, and just enjoy the quality and fruits, you will never ever face any problem. Moment we start applying our smartness we doomed and results are beyond imagination even if initial results appears good but then long term reliability goes for a six.
Let us take another example manpower if you do not hire right manpower you will never achieve six sigma irrespective of how much training you impart it will be futile. Manpower working on machines should behave like a robot or an army person do whatever is told to you do not fiddle with anything in the production. You should run the machine, check the output as given in instruction record it and pass it to the next stage if anything unusual found from the defined instruction stop and report. Any person having casual attitude or smartness is dangerous for your process and product, remove him till you find the right person.
Crux of the article is that there is everything defined when we start any production in the world only thing is we have to just follow and we have to have right manpower and attitude then we have already achieved six sigma.
It is child play like children play building block and make shapes one wrong step the shape will be different similarly six sigma is like building blocks of man, machine, material, knowledge, training, discipline and attitude everything is predefined and if use rightly you are already six sigma black belt.
My purpose of explaining above is that machine manufacturer recommendation is like a bible just follow it religiously similarly for consumables manufacturer, hand soldering manufacturer, packing material manufacturer even a small item like glue, ink, stickers just do not divert from the recommendations, study in detail the whole purpose of each small aspect and follow it blindly else you will be in deep trouble.
Now if you develop that attitude then it is first and last step towards six sigma you just need to know the tools how to collect and record the data your Cp and Cpk will be same always for everything in your company.
Manufacturing is a long journey like on a Highway where you keep moving smoothly at constant defined speed and enjoying it. Red light, petrol pumps are the stops where you do maintenance of your machine and punctures or breakdown are some unexpected point which is inevitable and are very few if everything is set right and food break is the point where you analyze how you are doing in your journey, whether you will reach in time to your destination or not. It is very simple do not make it complicated.
Parminder was involved in the early days of fully automated SMT lines in India. A Mechanical Engineer, serving the SMT Industry for 27 years with a Masters degree in Process Engineering, he worked in Telecommunication, meter, Defence equipment’s, Indian Railways, LED, EMS work for COMPAQ, IBM, DELL and Tandon Corporation. He has setup many SMT lines in India and can be reached via email email@example.com