Process Input Machine - Manufacturing Equipment monitoring and preventive maintenance.

After the equipment is qualified and in mass production, all optimized parameter setting should be documented in standard operating procedure (SOP).  Production should follow the same setting to reduce variation in the process output.  There must be performance monitoring of the equipment and total preventive maintenance (TPM) system set up.   A good metrics to use for monitoring the performance of manufacturing equipment would be overall equipment efficiency, OEE, developed by Seichi Nakajima in 1960s. OEE address equipment losses due to plan and unplan shutdown, production adjustment, idling, speed, quality defect and reprocessing : -

Calculated based on
uptime and downtime
total output, operating machine speed and time
Yield rate
OEE % =  Availability X Performance X Quality

From the above table, in order to calculate OEE, manufacturers need to setup proper data collection infrastructure which should be included in the planning phase of equipment setup per my previous article. OEE ought to be reviewed by management on regular basis.  There should be a management goal or target set for OEE metrics and investigation must be conducted if OEE does not meet the target.  The better the equipment efficiency,  the higher the OEE value.

In order to optimize OEE, it is utmost important that the equipment is well maintained base on total preventive maintenance (TPM) system.  Total preventive maintenance concept was also founded by Seichi Nakajima.  TPM is aim to achieve Zero Defects, Zero Breakdown and Zero accidents in all functional areas of the organization by involving all levels of people in organization to promote self-maintenance.  The table below shows the eight pillar use in TPM.

TPM Pillars
Autonomous Maintenance

Person who is using the machine such as operator own equipment daily maintenance through step by step approach that include inspection and cleaning.  This will free up the time of maintenance team to focus on specialize maintenance and improvement work. 
Focused Improvement

Small group of dedicated equipment specialist to conduct complicated PM work.  They should review and analyze the OEE data to find incremental improvement opportunity for equipment towards Zero Defects, Zero Breakdown and Zero accidents
Planned Maintenance

1.   Maintenance planning should take into consideration of available resources and number of equipment need PM.  
2.   Determine the preventive maintenance interval from daily, weekly, monthly, quarterly to yearly and what are the PM activities should be carried out.   PM interval could also base on production volume.
3.   There should be auto trigger system before PM due date to the management and equipment owner
4.   Ensure the planned maintenance is feasible to be carried out by the maintenance team
Quality management

Equipment has the capability to have auto warning such as andon light if there is error.  All warning must investigated, documented with action plan.  A study must be conducted on how to prevent any error.
Early/Development management

Established proper documentation which include lesson learned on the current equipment from qualification to sustaining phase. Apply the lesson learned in the future new equipment.
Education and Training

Person who conducts preventive maintenance must be trained and certified.  For complicated equipment, the training and certification should be done by equipment supplier.

Safety Health Environment

Sustain a safe and healthy accident free working environment
Administrative & office TPM

Reiterate the TPM principles beyond  manufacturing equipment in the production floor

The recommended activities for preventive maintenance are:

  1. Preventive maintenance activities generally consist of inspecting the equipment parts for wear and tear, replace short usage life part before they worn out, cleaning, lubrication for moving parts. 
  2. All preventive maintenance action must be recorded. This encompass parts that was replaced.
  3. Document PM Activities in checklist format to ensure all PM are carried per PM checklist and according schedule date.
  4. After a major preventive maintenance work, actual production parts must be verified before handover for mass production.  This is known as 1st piece verification done after major PM.

In order to prevent downtime due to unavailability of equipment spare parts, the PM team must setup a spare part management system and keep stock for frequent replaced parts.

Automated manufacturing is mostly suitable for high volume low mix type of manufacturer due relatively longer model conversion time compare to manual/semi auto line. 

Complicated equipment which need  expert maintenance

Manufacturer had perceived that automation will bring cost competiveness into their product, which in actual fact there are also hidden cost in maintenance of the equipment.   There are many  Japanese/Korean/China  multinational  brand suppliers (LCD, battery cells and semiconductor) invested  millions USD to purchase a fully automated manufacturing line,  however there are only a handful who had qualification, monitoring and maintenance system to match the investment made in equipment acquisition.  Automation can produce consistent good or bad parts, therefore a lot of planning by expert must be done to ensure only consistent good parts being manufactured and maintained.

Process Input, machine - Manufacturing Equipment qualification

Automation had been the main driver for cheaper, mass production goods in the consumer market since post world war II.  In electronics gadget supply chain, the higher tier supply chain such as electronics and piece part mechanical component are made from fully automated manufacturing line as this is marketed as mass production commodity part.  Most of the downstream supplier use manual assembly process.  However with the rising labor cost all over the world especially the global manufacturing hub China, most of the manufacturers are now looking into automation solution for their manufacturing process. 

An automated manufacturing equipment

Since manufacturing line automation and equipment is the part of process input, machine, governance process is vital to ensure that variation from automation and equipment is controlled and managed to minimize its contribution to the process variations.    

A fully automated manufacturing line for battery cell assembly process
The qualification of manufacturing process machine is much more complicated compare to jig and fixture qualification featured in the previous article (21 Oct 2017).  As manufacturing equipment is a major capital investment, therefore there should be proper planning before acquisition of the equipment to ensure optimum return on investment (ROI).  Acquisition and setting up equipment is a project by itself, therefore it must follow the proper protocol of project management process which consists of initiating, planning, executing, monitoring & controlling and closing before being hand over sustaining process.  Below are recommendations for activities in each phase:-

Consideration points/activities recommended
Define the purpose of the equipment, function needed and who are the stake holders at both supplier and equipment user. Consider the following factors before investing:-
  1. Production volume of the part,  prefer high volume manufacturing
  2. Utilization of the equipment
  3. Current equipment technology suitability for the manufacturing the part per customer requirement
  4. Equipment capability
  5. Ease of maintenance
  6. Spare parts availability
  7. Warranty, service, training provided by equipment manufacturer
  8. Reputable equipment vendor who can provide good service to minimize unplan equipment downtime situation.

Once the equipment is identified for purchasing,  planning should be made for acquisition of the equipment.  This include scope, scheduling, resources- human, space, etc., quality,   cost, and communication from internal to equipment supplier, risk, and procurement of the equipment.  There should be planning for process input and output for each element in planning. 

Performed all the work per planning phase until the equipment is fully commissioned on site.  It would be best to deploy design of experiment study to determine which machine parameter setting would impact output Y and optimization. DOE will be discussed in future article.

Monitoring & controlling
After equipment is fully installed,  there should be monitoring on the performance of the equipment during pilot run which include :-
  1. Production rate
  2. Yield rate
  3. Process capability study on critical to quality parameter
  4. Overall equipment effectiveness (OEE) a metric which multiply productivity, quality and availability. OEE is also an important metrics in lean. Please refer to my next article for detail on OEE.

All the above study must be based on schedule plan developed during planning phase with goal setting for pilot run. 

If any quality or productivity metrics does NOT meet the goal defined during planning phase, there should be feedback loop for improvement before mass production.

Closing & Sustaining
Once pilot run is completed,  then there should be a handover of the equipment to the sustaining equipment department

Design of Experiment approach to optimize equipment setting

The above is very compressed summary of project management approach to setup manufacturing equipment or even an automated manufacturing line.   Project planning should be done by subject matter expert and project management professional (PMP) especially for big automation project. Unfortunately most of the high technology electronic component suppliers who had invested millions of dollar to acquire highly sophisticated are not aware that investing in planning and qualification of the equipment is equally important.   Having the privilege to qualify a few high technology electronic component new manufacturing line during my career as supplier quality manager,  it is ironic that none of the suppliers are aware of the project management approach to set up new manufacturing equipment or line.  There are no proper DOE conducted to find which equipment parameter had an impact product performance follow by optimization. Trial and error study is mistaken to be DOE!

After the qualification of the automated manufacturing line or equipment, it is imperative to setup proper monitoring system and preventive maintenance.  This will be the main focus in my next blog.

Process Input, machine - Jigs and fixture from qualification to maintenance in mass production

In this article, I shall focus on variations contributed by process input, machine.  The word “machine” in this context span from small jigs and fixture, semi automatic equipment to high technology fully automated robotic manufacturing line. 

In electronic industry ecosystem, high tech commodity product such as IC, semiconductor components, battery cells, PCB,  mechanical piece part, memory modules, LCD display,  are produce using  semi to fully automated equipment.  Therefore machine could be the major contributor of process input variations.

Assembly process of fitting all the above high tech commodity parts together to form a finish electronic gadget such smart phone or tablet is more manual process.  Most the assembly process are still make by human hand.  In good manufacturing practices,  we would use jig and fixture  to aid operator in assembly process,  therefore machine is still a contributor to a certain extend.
Machine use to aid manufacturing need to be qualified,  setup by expert and maintained correctly in order to minimize the variation contributed by “machine”.  In part 1 of this article we shall concentrate on jig and fixture qualification  and maintenance in mass production. 

Jig and fixture is used under 2 main situations

Manual manufacturing process
To aid operator in transformation process  such as simple cutting jig or
To help support part and guide operator to assemble parts
More consistent part,  such as cutting part with cutting jig,  length will be more uniform
High technology manufacturing process equipment
To reduce the changeover time of equipment by converting a portion of the equipment for changeover of parts
Shorter equipment conversion time

There is a subtle difference between jig and fixture.  Jig is use to aid operator in the transformation of part and fixture main purpose is to support the part during transformation/assembly process.  Good reference to jig and fixture could be found in this link

Jig and fixture  as part of process input, machine, need to be qualified, setup and maintained properly to ensure it helps to reduce process variation to get consistent good quality part.

Recommended practice for Qualification of Jig and fixture
  1. Understand why a process needs a jig or fixture,  and conceptualize the design 
  2. Design of the jig should into consideration if it will cause handling, ESD problem to the part.  Material selected should not be easily subjected to wear and tear. 
  3. Develop jig and fixture drawing with necessary details  :-  dimension and tolerance, critical dimension clearly marked and specify material required for the jig and fixture.
  4. Jig and fixture supplier should fabricate the jigs and fixture according to drawing and buyoff the jig and fixture according to design drawing with official first article inspection report.
  5. Manufacturer must have identification system which ensure all jig and fixture had a unique identification number for traceability.
  6. Manufacturer should create a masterlist for all the jigs and fixture in factory which consist of the following information :-  Jig ID,  Jig name/description,  purpose of the jig,  process used,  FAI date,  drawing,  qualification date and results,  PM required.
  7. User factory of jig and fixture should create a process to buy-off jig and fixture which comprise of  :-

  • Checking the jig and fixture per drawing and first article with proper report
  • Trial  the jig and fixture in production line and record the results of the parts and cycle time. 
  • Specify the length of evaluation and how many parts need to be evaluated.

  •  Evaluate the key process input Y of the part such as attribute  reject rate, critical to quality parameter variable output.  The qualification best practice would be using process capability index (Cpk/Ppk) of the impacted critical to quality process output Y.  

Fixture which help to support the part , operator do not need to hold part and apply glue result in more consistent gluing process

Typical drawing of fixture

 Jig and fixture could be subjected to wear and tear or shift in performance over time in production,  therefore preventive maintenance is necessary  to verify the jig/fixture on regular basis.

The preventive maintenance of jig and fixture should include the following

1.   Determine the preventive maintenance base on production volume or  interval (months or quarterly)
2.   Establish all the checking criteria for jig and fixture  clearly documented in procedure
3.   There should a master list to track the preventive maintenance due date and auto trigger to the jig and fixture owner in the process.
4.   Create checklist on checking items and record all checking items and condition of jig and fixture. 
5.   Assess if there is any part of the jig and fixture which need to be replaced and record the replacement if necessary.  This can be used to determine if the frequency of the preventive maintenance.

Jig and fixture could help to create a consistent good products if  qualification, set up and maintenance is done properly.  On the flip side it will create problem if there is governance process to manage jig and fixture used.

The Human Factor Contribution to Process variations– Part 2

In part 1 of this article, I have emphasized on managing indirect labor and some of the aspect managing indirect labors apply to direct labor as well.   Manufacturer which has a lot of manual assembly process should focus on managing and controlling direct labor, human operator. 
Although there have much advancement in automated manufacturing process, manual product transformation work by human is still very crucial in many cases.  Direct labor has a direct touch to the transformation of the product and it is vital to ensure we have a direct labor workforce that is trained and consistent.  Key tenets to direct labor workforce consistency include training, certification, performance monitoring and retention.


The organization ought to have direct labor training department which specialize in manufacturing process training with certified trainers.  Training system should include interactive classroom training which cover all aspect of the process.  Once the classroom training is completed,  then the operator should be go through on job training  (OJT) on the actual process with proper monitoring from the trainer for a duration according to training procedure.  Training should also include part handling as reject could happen during part handling between process rather than transformation process itself.
It is good practice to organize training approach base on the type of assembly process, its complexity and skill level required for the process.  An example a soldering process operator would require higher level skill set compare to a packing or labeling operator.  The criteria used to certify different work complexity/skill level worker should also be different.


Operators should be certified through an objective evaluation process, which could comprise of written examination and OJT evaluation from certified trainers.   Trainer need to assess on how well the operator follows the work instruction in the process and the output from the process which is free from defect.  Clear criteria for certification could consist of
  • Length of OJT
  • Count of parts the operator produce
  • Operator cycle time
  • Count of defect parts from the OJT operator

Performance monitoring

After operator had been certified, there should be a regular performance monitoring to ensure operator realize that they are being monitored and received feedback about their work.  Performance monitoring could include work attitude, absenteeism, actual work, compliance product rate etc.   There should disciplinary action taken when necessary
There are a few companies who practice recertification on yearly basis.  If this is case, then there must an automated recall system available to do so.   Recertification is compulsory for operator who had been away from the work for quite some time, eg.  maternity leave or transfer to other process.

Cross training

Objective criteria to select operator for cross training is necessary based operator skill level.  It is advisable to limit the number of cross training for each operator.

Staff Retention

It is imperative to have a stable direct workforce as only through a stable direct workforce we can maintain the consistent good quality product. There should be an equally attractive reward and motivation to help reduce attrition rate.

Process input variation contributed by man is the most difficult to handle.  Human is very complex with different personality will operate differently which contribute to variations.  There is no one size fit all approach in dealing with individuals.  Human is the one that give rise to quality problems and they are one who can resolve quality problems as well.

Once there is a consistent process screening the right candidate for the right functional role from top management to working level,  consistent training process for each functional role,  with right motivation and quality mindset,  all the rest of the process input  variation machine, material,  method, measure and environment can be managed and controlled to produce consistent good quality product. 

The Human Factor Contribution to Process Variations– Part 1

By now we should be very clear that  as  a manufacturer of any products we would like to  deliver consistent good quality product to attract our customer.  In order to achieve consistent good quality product which is process output,Y, we must understand and control the cause of  variation.  Cause variation derives from various inputs Xs (5M and 1E) which needed to transform material to output, Y,  which is a product that will be eventually sold to consumer.  

Process input man is the human factor

Out of the 6 process inputs,  I have already discussed very extensively on process input, measure  in 5 articles published on 28 Sep, 29 Sep, 6 Oct, 9 Oct and 12 Oct in this website.
In any organization,  human resource is vital  to a success of the organization operation, which include manufacturing process.   We cannot limit process input, man, to operator who directly transform the product in the manufacturing process.  Instead we should focus end to end of man contribution from management team, engineers, trainers to operator.  In most company management team, engineers and trainers are known as indirect labour (IL) and manufacturing operator as known as direct labour (DL).   It is biggest sin in manufacturing entity to blame poor quality product on operator.  We must remember and adopt Dr Deming lesson that 85% of the quality problem are cause by poor management (IL)  at all times.  If you deal with suppliers as asupplier quality engineer(SQE), account manager or commodity manager, when you spotted a misconduct in operator,  you will need to question the management instead of the operator.  Operator merely follow instruction from management team and/or engineers/trainers. If there is a misconduct, this could mean that the management team did not give direction or conduct any check and balance on operator.  This happen due to a lazy management team or sub standard knowledge management team.
Key to success in managing and controlling human factor to achieve consistent good quality product would be :-

Top management

Manage and control of process input, man, should start from top management  such as the company owner or the top executives.  The organization top management must have the clear quality mindset and understand everybody in supply chain who is involve in bringing the product to the consumer market contribute to the product quality.  Ideally there should be a good hiring process to hire everyone with quality mindset,  however this is not possible.  Therefore it is a good practice to hire at least key position manager with knowledge in quality to drive the entire organization.  The company should be very fortunate if they get customer in the role of SQE with quality mindset to drive them as customer is biggest change agent for any organization.

Hiring process

The hiring process in a successful organization must have the capability to get the right person for the right job.  Some companies  use personality test  such as Briggs Myers'  test or or some unorthodox method such as Chinese metaphysics Baizi profiling to understand potential candidate personality besides assess the candidate skillset base paper qualification and experience.  In my personal opinion this is a more balance approach, as both qualification and personality will determine the candidate’s potential in the position.  A candidate who is able to perform at optimum level in a  job function will  have positive impact on product quality of the organization.  So far I have never hear of personality test being use in the manufacturing industry.
Sometimes hiring good quality (personality, experience and qualification) engineers or managers might cost a bit more,  however it is worth the investment as this could have prevent any potential poor quality cost.  

Remember pay peanuts get monkey!
Company Culture

Quality awareness should be from top down.  Quality mindset should be  instill in  all employees as quality is everybody business.  Each and every employee should be motivated to perform their best at all the times then only  consistent good results can be attained.  In  late 1980s to early 90s when I  just started my career most company management were dictator style.  As we move towards a new millennium most company had shifted their management paradigm to more open style  especially in managing generation X to millennials.

A superior culture w to adopt in an organization would be lean culture. So far in my career as supplier quality manager dealing with hundreds of company across the globe I have NOT seen  a true lean culture company.  I have seen quite an number of bogus lean companies or organizations that mixed up six sigma and lean!

Learning Opportunity

There must proper training structure in place to ensure the IL workforce is being systematically trained related to their job function which enable to contribute to the product quality. Company should send various functional  engineers  to quality related training to ensure they understand that they play a role in ensuring the quality of the product.  It is best to recruit or train quality engineer to become certified quality engineer by American Society of Quality (ASQ).  

Performance monitoring

Quality should be the main key performance index (KPI)  driver for management and management must have the capability to drive quality related  KPI to the rightful process owner from various functional group.  One of the most important KPI should be quality cost and there must be a systematic and consistent measurement of quality cost across organization.

Staff Retention

Manufacturing industries especially electronic related are very dynamic,  therefore  it could have the highest attrition rate compare to other industries.  An organization should always setup a system which has very little dependence on individual worker.  Critical projects should be handled by a team and not by an individual.  Although nobody is indispensable including the CEO,  however if the a key person leave the organization it might cause problem that could contribute to product quality. 

An example would be if the instruction of how to make a product is control by one engineer and there are no proper documented procedure,  then the knowledge will be lost if the person leave the company.  The company must have a quality management system which ensure all process are well documented and updated. 

Finally top management should developed an attractive remuneration package, good working culture with advancement opportunity to retain all the good staff.  Some multinational corporation had even created a comfort zone for their employee to retain their talented staff.

We shall focus on the guideline to train and certified operators to ensure the variation from trainers and operators are being managed in my consecutive blog.

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