Line Balancing Tool Based on Operator Skill Matrix

 In a garment factory, when we see there is enough loading but production is not coming out from the line as per the input, we simply say there is a problem in line balancing. 

 From the top management to the worker everyone knows a better line balancing can improve line output – but many of them including engineers don’t know the right way of balancing a line when there is work pressure, employee absenteeism, low skilled worker etc. In this post, we will discuss about useful line balancing tools.

1. Funnel effect

If we imagine our production line like a tube, then each operation capacity must be close to a circle from the tube (picture 1). The radius of the circles must be similar to the radius of the tube, in order to be the line balanced. If the radius of the circles is different, our tube will become a funnel whit different forms, and the output will be the smallest circle (picture-2) of the funnel or any other form which our line will take it.

Sure, in order to balance the line, during the production, will be applied corrections like overtime and/ or supplementation of the workers from other production lines, … but all these actions will decrease real productivity and will increase the cost per minute.

2. Preparing of Production Lines activity equilibration

• Prepare the Operation breakdown and define the correct SAM (SMV)
• Measure operators’ efficiency, using, at least daily data collection ( better online data capture system)
• Define the operators’ skills matrix (the efficiency of the operators in different operations and skills)
• Define the Line Target using the above-presented formula, taking in consideration.

Operator skill matrix definition:

In the case of online data capture systems, the efficiency of the operators on different operations is given automatically. In the case of Daily data collection, skill matrix can be prepared in the SFC system using an algorithm. to make an average of the efficiency of the operator in different days when has worked a full day (or less 90- 80% from the day depending on system setup) on the analyzed operation or skill.

Types of Operator skill matrix

1. Efficiency on the operation code. Examples:

• Operation 1: Sleeve bottom hemming using folder
• Operation 2: Polo shirt bottom hemming before side seam, using folder
• Operation 3: Sign front placket
• Operation 4: Sign front pocket position

2. Efficiency on the operation skill: Skill 1: Bottom Hemming using folder and Sign 2: Sign

Define the Line Target taking into consideration the following

1. The need for special machines – to not plan more persons on special machines than you have
2. The 4 different efficiencies when is defined as the planning efficiency, used for target calculation.

Efficiency-1: Historical global achieved efficiency of the workers


Efficiency-2: Historical maximal efficiency of the workers (The average of maximum efficiency of the workers). This shows us what is the theoretically maximum achieved efficiency of the workers when
– The workers were planned to execute the operation where has the best skill and rhythm.
– The operators had loading all day
– When the operator had motivation


Efficiency-3: Line balancing efficiency. The resulted average planned efficiency of the workers using the under described Line balancing tool.


Efficiency-4: Realized efficiency. The average efficiency of the workers day by day after launching the current product in the line.

Important notes:

If the Line balancing efficiency is higher like the Planned efficiency, then for the same target you will need less No of workers, or with the same number of workers you must to define higher target (higher planned efficiency) if the remained worker can be integrated in Line balancing, without decreasing the efficiency of the planning.

If the Realized efficiency is lower than the planned efficiency, and if can’t grow up the operators’ efficiency with workplace optimization, training.., then:

• Must be analyzed again with the under presented Line balancing interface the equilibration between operation and operators and in case to be redefined the Line target (Sure this will cause the delay of finish date)
• Must to be planned overtime in different operations in order to keep the line balanced (Sure this will cause productivity decrease and costs increasing)

• 3. Prepare the Line balancing sheet

         

  In the above presented Line balancing interface the work method is –

1. Select the manufacturing order (operations and SAM) and the production line/ group (persons) where is planned to be executed
2.  Set the correct target/day in the left up-side of the screen based on the formula and method presented before, defining the number of workers and the planned efficiency.
3. Plan the target quantity from each operation for the correct operators, using the following instruments.

– Operation rating for persons. With a left click on “i” (information’s) button of the operation, the system will offer the rating of the persons in the database regarding the achieved efficiency on the selected operation and in the skill of the selected operation separately. The system also gives the same rating of the free (unselected) operators in the current balancing sheet.
– Person rating on different operations. Positioning the mouse on a person “i” button, the system will offer the rating of the efficiency of the person, from the system database, on different operators and skills separately.
– Person rating on the selected operation. Positioning the mouse in one point in the operation/ operator matrix the system will show the efficiency of the selected person on the selected operation and Skill.
– Allocate gradually more with 5 – 10% like the person’s efficiency on the current operation, especially for the persons under 100% efficiency, and follow and support those persons in order to increase the efficiency.

Line balancing methods:

1. Operation based – Plan first the difficult operations and all the target quantity
2. Person based – Plan first the persons in the possible higher eff. Operation
3. Combined – Plan first the difficult operations, but take in consideration if one person from the rating of the current operation has higher efficiency in other operation.
– Plan the person on other operation where has higher efficiency like on the current operation only if the operations have the same difficulty levels
– Plan the person on other operation where has higher efficiency like on the current operation even the operation with higher efficiency has a lower difficulty level

4. Implement and follow the Line balancing

Implement the rule in the line: INPUT = OUTPUT = TARGET

Do not input more.  Define the target of the line to avoid the “funnel effect”.

Assure the loading in critical points using one of the methods:

• Implement strategic inline stock before key points
• Use Jokers, which are not allocated in line balancing sheet, but are taken into consideration in the Target calculation formula!

Sure, the best situation is when you have enough multi-skilled operators to not need to invest in one of the presented solutions to avoid having an unbalanced line and productivity decreasing because of absenteeism, inline quality problems, efficiency variations …

Use a similar sheet, like under presented (based on line balancing sheet) to follow, at least the critical points, min 2 times/ day (preferably each 2/3 hours).

In the above sheet, the “Plan” columns are based on Line balancing sheet, and the “Real” columns will be completed manually (if is no online data capture) during the day, in order to be visible the line balancing problem at one it appears.

Hope you find this post useful.

About the Author: This article is written by Marthi Bela. He is an ERP, PMTS specialist and Garment Industry expert.

RFID System for Production Tracking in Apparel Manufacturing

 For real-time shop floor production tracking and production monitoring in apparel manufacturing, RFID technology is one of the commonly used systems. In this post, I have shared a production tracking system used in a garment factory for real-time production monitoring. RFID stands for Radio Frequency Identification.

I don’t need to mention that we all like faster product delivery and quick response to the market. We use many mobile applications in our smart mobiles for managing our personal life. When the apparel industry going for smart manufacturing, machine learning, using IoT, AI tools, apparel manufacturers feel the importance of data for managing their production floor – Why we can’t have a real-time production tracking system for the production floor to manage the production in a better way?

When you do manual production tracking, you count garment production hourly or bi-hourly. You count production from the end-of-line output. You count sewing operators and helpers in a line. You update production quantity on the Hourly Production board. You get the production status of the whole factory after one day. That is too late for decision making and fixing production problems. What if you get the production update after each garment is stitched and completed in each workstation?

Let me explain what we mean by production tracking in a garment factory. Production tracking means more than only counting pieces at the output operation and operator head counting. Getting production counting from each workstation (operation-wise as well as operator wise production data), knowing how operators spend the given time when they are on the shop floor.

Purpose of the RFID system for apparel

The primary objective of an RFID based real-time production tracking system is capturing real-time data and viewing the report in real-time.

Improving process visibility and transparency. Accuracy in production data.

Data capturing and getting data automatically through scanning RFID tags in the workstation. Once you have captured data from the desired activity in the pre-defined parameters, you can play with the data and build reports and KPIs as you need.

I have seen a couple of  real-time production tracking systems that are helpful for production tracking and production floor monitoring. I will be referring Blue cherry Shop floor control system for explaining the RFID system, the workflow of this system.

RFID System Workflow in garment manufacturing.

There are many technical terms and data designed based on capturing data and storing data in different database tables to retrieve the report for various purposes. I am not going to bore you by explaining technical things here. Instead, I will show how this system works and what kind of information you need to enter into the system before you can scan the RFID tags.

You need to install the operator’s device (called as sewing operator terminal) at the workstation. Connect the device through wiring and networking cable. It can be a wireless device. Installation of the device is decided according to how you want to capture production data and workflow of garment components in a production line. I mean, you can install a separate terminal for each employee, you can install one terminal for a group of employees who are doing the same operation in the same place. And the group is working on the same bundle.

After installing all the hardware components, you need to set up data in the system.

Create a master for employees, line and sections. Add plant details, work shift detail.

Add masters for jobs – you need to create a database for a list of tasks (operations) you do for making your apparel products. You have a code number for each job (sewing and non-sewing activities in the manufacturing related to processing style).

Add operations and style – for a new style you need to create operation adding operation SAM, sequencing of operations in a style, connecting the style with a production line. Marking operations will be the starting point of the style and components. This is like an OB you make in an Excel sheet.

Entering data for order, lay and bundle listing – In practice, apparel manufacturers lay the fabric on the cutting table and cut the fabric as per marker plan. In a lay, you cut multiple layers of fabric plies and multiple markers. You maintain the record of orders – number of lays for completing whole order – size-wise and color-wise cut quantity in each marker. Finally cutting department makes bundles with few garment pieces (10-20 pieces per bundle).

In the production line, operators get bundles and the work on it and move the completed bundle to the next operator. In the database you need to create bundles – maintaining the same order of data hierarchy – one Order – multiple lays (cut) in one order – multiple bundles (size and color wise) in one lay – a few garments in each bundle. Combined bundle quantity should be the total order qty.

Assignment of RFID tag against each bundle – after making the list of bundles, you need to assign an RFID tag for each bundle. You can make more than one bundle tag for a bundle. By making multiple tags for the same bundle, operators can work on the same bundle parallelly. For the identification of bundle (style, order number, garment color size), the label is attached to each bundle. 

Attaching tags to bundle – You attach a tag to each bundle before loading it to the employee. The RFID tag can be attached to a bundle in the cutting section or you can attach to the bundle in the feeding area. Here I would like to add bundle /piece can be loaded in various ways in the line.

• moving bundle throughout the line
• moving a single piece throughout the line
• feeding bundle in preparatory section but move a single piece in the assembly section
• loading bundle to all operation but want to count pieces one by one
• loading different bundle components at different places at the same time – parallel loading.

All these kind of bundle movements can be adopted by RFID tags assignment and operator terminal profile.

Operator terminal – Set up operator terminal with the operation code and make ready for scanning tags. Operators login to the system by entering their employee code into their terminals. Once they login to a terminal, all kinds of transactions processed into the terminal, are recorded against the employee.

Scanning RFID tag for production counting – Before an operator starts working on a bundle, they scan RFID to the sewing terminal. Once garment bundles reach to the operators, they scan the RFID tag to their terminal. System capture all the transactions performed at the operator’s device. The system captures their transaction and bundle qty as production quantity.

Other kinds of transactions – Other than scanning bundle tags there many other different transaction operators can do as per there need and data required by the factory. Like, the operator can split the bundle, they can log-out from one workstation and work another workstation by login to another terminal. If they work multiple operations, they can change the operation in the terminal. In case an operator gets the whole lay and do the continuous work, scanning of individual bundles can be avoided, by using bulk operation function.

The operator sees their production, earning and performance in the terminal. The operator can send an off-standard request to line supervisor by entering off-standard code in her terminal. A supervisor can approve the off-standard code required on the terminal or from the computer 

The basic requirement for installing an RFID system

• You need hardware and software for installing the RFID system. The software and hardware are normally supplied by the supplier. Other than these components, you need the following
• IT Team – IT team needed for networking, server maintenance. 
• Computer, Server, internet (intranet), printer and database
• Industrial engineer for Data preparation and report viewing. In the system, you need to enter style data with operation SAM. You know, only an industrial engineer can establish garment SAM and operation SAM. In a factory, IE is responsible for operation SAM. Sequencing of the sewing operations in style also needed. Without an IE team, installation of the RFID system, would not be possible.
• Training of sewing operators – Sewing operators need to be trained on how to use the terminal. Supervisor and line leader need to be trained for basic troubleshooting on the floor.

Benefits of RFID System in production tracking

When you have an RFID based real-time production tracking system, you will have a database. You have the flexibility of making reports in many ways as you want. Factories that have a strong IT team and having knowledge of programming and making a report from SQL database, can easily make a useful report for the management and factory. Customized production reports can be made in Crystal report, Excel-based reports using SQL queries.

With this system, the data recorder and line supervisor cannot give you inaccurate production data. As operators get an RFID tag for the garment she stitched. 

Manual data collection and report making can be eliminated by installing a real-time production tracking system. All production data, lost time data and quality data will be captured from the operator’s device and the system will process those data and report will be made automatically in the pre-fined report templates.

Improved visibility and transparency. You can view production data from a remotely having internet connection. Managers can review data for all sections and lines. They can compare performance between the line. Can track order status, WIP.

Some of the common reports factories views include

• Hourly production report
• Line wise employee attendance and absenteeism
• Previous day’s employee wise production, operation wise production
• Today’s line efficiency and previous day’s line efficiency
• WIP report
• Individual operator’s efficiency and skill history

With the real-time production tracking system, you can introduce an incentive scheme for sewing operators. You know the incentive scheme is the main driving force for productivity improvement in the shop floor. For designing an incentive scheme, you need production and efficiency for individual employees. With the real-time production tracking system, you will have all the basic data you need for an incentive scheme and calculating the employees’ bonus amount. Operator incentives can be designed in various ways – like individual performance, group performance, a combination of group and individual performance.

You can eliminate the bar-code system on the production floor, in case you are already having such a system.

Your operators don’t need to writing production quantity in a piece of paper.

You can integrate other modules in the production tracking systems – like real-time Quality control system, machine maintenance module.

RFID tags are reused until the tag get damaged. Even one tag can be used for more than 10 years. So, no expenses in RFID tag.

A time-saving tool for industrial engineers. In a garment factory, IEs spend a lot of time in daily report preparation and data analysis. Data preparation can be eliminated by introducing the RFID system.

Improving productivity – All applications and software commit that it will increase the factory’s productivity. But how? A system can only provide data – you need to take action to get the benefit

Lost-time data – by capturing lost time data, you can find major reasons for efficiency losses in production. After getting lost-time data, if you act and reduce lost-time, your productivity will improve.

Limitations and challenges of an RFID system in apparel

I am implementing the RFID based real-time production tracking system for 8 years. I did the implementation in many garment factories covering 5 different countries. I have worked with the shop floor team, IT team and engineers. I will share some of the challenges that factories faced.

Each factory is unique, and different garment factories view daily production reports in different formats. The inbuilt reports in a real-time production tracking system are limited. In case the factory wants additional report matching with their existing excel reports, suppliers can develop the customized report with/without additional charges.

The involvement of the line supervisors, line leaders and sewing operators is essential for a successful implementation. Sometimes questions come – why operators should spend time on scanning RFID and follow the new system if they are getting any benefits from this system (in the salaried environment).

I have seen real-time production tracking systems is used as standalone software and not integrated with the ERP and payroll systems. Engineers become the lead for the system installation and maintaining the system. When an IE leaves the factory, factory face issues in maintaining the system.

During the implementations, factories develop many custom reports. But after a few months, they used to view and track only a few reports.

Most of the factories I had worked with do not have a database team (IT team having knowledge of SQL DB and report preparation from SQL database) for developing reports internally. In such a situation, factories can’t utilize the data they captured. 

Conclusion

I understand it is not possible to understand and visualize the whole process of the RFID system and its use in a garment unit by reading this short article. I have explained only major activities with brief notes and without any example. My objective of sharing this piece of article is to make you aware of how the RFID system works in an apparel manufacturing unit.

The technical things and actual working method can be learned when you install such a system in your factory. There are a few companies who provide real-time production tracking solutions, most of them use RFID technology for data capturing. The working method and data preparation may vary from one product to another.

For tracking the real-time shop floor production data, RFID systems are good options for the garment factories. The benefits of this system are enormous if you can fully utilize the product.

Written By: 

Prasanta Sarkar

Textile engineer and a postgraduate in fashion technology from NIFT, New Delhi, India. 

Eight wastes of lean manufacturing

       Today, the Lean Manufacturing model recognizes 8 types of waste  within an operation; seven originally conceived when the Toyota Production System was first conceived, and an eighth added when lean methodology was adopted within the Western World.  Seven of the eight wastes are production process-oriented, while the eighth waste is directly related to management’s ability to utilize personnel.

The 8 wastes of lean manufacturing include:

1. Transportation

Poor plant design can cause waste in transportation.  It can also trigger other wastes such as waiting or motion and impact overhead costs such as higher fuel and energy costs and higher overhead labor in the form of lift drivers as well as adding wear and tear on equipment.  It may also result from poorly designed processes or processes that have not been changed or updated as often as required.

Value stream mapping and partial or full changes in factory layout can reduce transportation waste. This is a full documentation of all aspects of the production flow and not just the mapping of a specific production process. This results in changes to reduce or eliminate transportation waste.

Common types of Transportation Waste:

• Poor layouts – large distance between operations
• Long material handling systems
• Large Batch sizes
• Multiple storage facilities
• Poorly design production systems

2. Inventory

Inventory is considered a form of waste because of the related holding costs.  This is true of raw materials, WIP and finished goods. Over purchasing or poor forecasting and planning can lead to inventory waste.  It may also signal a broken or poorly designed process link between manufacturing and purchasing/scheduling. Lean Manufacturing does not just focus on the factory but also requires process  optimization and communication between support functions.

Purchasing, scheduling and forecasting can have a version of standardized work in the form of defined minimums and maximums and order points that are mapped to the process flow and takt time. Purchasing raw materials only when needed  and reducing WIP and eliminating or narrowing the definition of “safety stock” will reduce this type of waste.

Common causes of Inventory Waste include:

• Overproduction of goods
• Delays in production or ‘waste of waiting’
• Inventory defects
• Excessive transportation

3. Motion

Motion costs money. This not only includes raw materials but also people and equipment.  It may also include excess physical motion such as reaching, lifting and bending. All unnecessary motion results in non-value-added time and increases cost.

Again, referencing core Lean Manufacturing methodology, process mapping should include facility layout and optimized workplace design that includes analysis of the distance of motion within the space as well as the location of parts, supplies and tools within the space as well.  As an effective process map is developed, proper utilization of the space can be captured with well designed and documented standard work.

Common Motion Waste examples include:

• Poor workstation layout
• Poor production planning
• Poor process design
• Shared equipment and machines
• Siloed operations
• Lack of production standards

4. Waiting

Waiting can include people, material equipment (prior runs not finished) or idle equipment (mechanical downtime or excess changeover time).  All waiting costs a company has in terms of direct labor dollars and additional overhead costs can be incurred in terms of overtime, expediting costs and parts.  Waiting may also trigger additional waste in the form of defects if the waiting triggers a flurry of activity to “catch up” that results in standard work not being followed or shortcuts being taken.

In many ways, waiting is the opposite of overproduction.  However, it can be mitigated or eliminated with many of the same remedies. Waiting is often the result of poor process design and can be addressed through proper measurement of takt time and the creation of standard work.

Common causes of Waiting include:

• Unplanned downtime or Idle equipment
• Long or delayed set-up times
• Poor process communication
• Lack of process control
• Producing to a forecast
• Idle equipment

5. Overproduction

When components are produced before they are required by the next downstream process, overproduction occurs.  This has several negative effects. It creates a “caterpillar” effect in the production flow and results in the creation of excess WIP  This leads to staging and therefore labor required to move the WIP additional times. And it can hide defects that could have been caught with less scrap if processes were balanced to allow detection earlier as earlier use of the WIP components would have revealed the defect in time to correct the issue.

Lean manufacturing systems utilize  several tools to combat overproduction.  Takt time is used to balance production rates between cells or departments.  Measured and process-mapped jobs result in reduced setup time allowing efficient small batch flow.  And in many industries, “pull” systems such as Kanban can be used to help control or eliminate WIP.

Common causes of Overproduction include:

• Unreliable process
• Unstable production schedules
• Inaccurate forecast and demand information
• Customer needs are not clear
• Poor automation
• Long or delayed set-up times

6. Over Process

Over/Excess processing is a sign of a poorly designed process. This could be related to management or administrative issues such as lack of communication, duplication of data, overlapping areas of authority and human error.  It may also be the result of equipment design, inadequate job station tooling or facility layout.

Process mapping is a lean waste elimination tool that helps define an optimized workflow that can eliminate over processing.  As a key method within lean production, process mapping is not limited to the performance of production tasks. It also includes reporting, signoff and document control.

Examples of Excess Processing include:

• Poor communication
• Not understanding your customers’ needs
• Human error
• Slow approval process or excessive reporting

7. Defects

Defects impact time, money, resources and customer satisfaction. Examples of Defects within a manufacturing environment include lack of proper documentation or standards, large variances in inventory, poor design and related design documentation changes and an overall lack of proper quality control throughout the process workflow. 

Formalized document control and design change documentation, thorough and documented quality methods in all production phases and checklists that have been audited to ensure proper adherence to the BOM are effective ways to control defect waste.  And standardized work at each production cell or point in the production line will help reduce this type of waste as well.

Specific Defect causes include:

• Poor quality control at the production level
• Poor machine repair
• Lack of proper documentation
• Lack of process standards
• Not understanding your customers’ needs
• Inaccurate inventory levels

 8. Non-Utilized Talent

The eighth waste is the only lean manufacturing waste that is not manufacturing-process specific. This type of manufacturing waste occurs when management in a manufacturing environment fails to ensure that all their potential employee talent is being utilized. This waste was added to allow organizations to include the development of staff into the lean ecosystem.  As a waste, it may result in assigning employees the wrong tasks or tasks for which they were never properly trained.  It may also be the result of poor management of communication. By engaging employees and incorporating their ideas, providing training and growth opportunities and involving them in the creation of process improvements that reflect the reality they experience and the skills they possess, overall operational effectiveness is improved. The elimination of this type of waste can improve all others.

Examples of Non-Utilized Talent:

• Poor communication
• Failure to involve people in workplace design and development
• Lack of or inappropriate policies
• Incomplete measures
• Poor management
• Lack of team training

Eliminating the 8 wastes of lean manufacturing is much easier when the production process is completely visible. Cloud computing, deep analytics and machine learning work in conjunction with devices, sensors and software adaptors to connect a factory and allow it to leverage hidden capacity for improved efficiency.  

Collected by: Md. Tarikul Islam Jony
Mail:jonytex073@gmail.com
+8801912885383

Lean Manufacturing tools series 20 (Hoshin Kanri)

Every organization exists for a reason. One of the main reasons is to earn profits. There can be other reasons for existence as well. On the other hand every organization has their resources like capital, organizational structures, processes, and people. You may be a follower of lean or not, but I am sure you will agree with me, it is very difficult to align all your resources to achieve what you want to achieve, especially when your organization is larger. If you are working with only handful amount of people it is mighty easy to achieve your goals. You can see each other working. You have a direct control. But when your organization is large, you will have different clusters, departments and divisions etc, etc. there will be hundreds or even thousands of people who are working for you to achieve your goals. Everyone needs to be pulling in same direction in order for you to achieve your goals effectively. But I am sure you would know, it is not easy as it sounds. 

Only very few people in an organization would be aware of the goals of the organization. Even if they know it only a handful would know how your organization is going to achieve them, or your strategies. Even if they know how they are going to be achieved, most of you will not know what is the part you will have to play in order to achieve your organization goals. Sounds familiar isn't it. Best part is, even if you know what you want to achieve, you wouldn't know how you, yourself and others are going to measure it.

So every organization has to answer few questions when they set up their goals and cascade them down the chain.

1. What is our goal? For an example “we want to be the #1 car manufacturer in the world”

2. How are we going to achieve our goal? For an example “we want to sell x million units of cars to become the #1 car manufacturer of the world”

3. What do we want to achieve the target? For an example “We are going to manufacturer the world's lowest cost car so that everyone can afford it”

4. How are we going to measure whether we achieved our objective? For an example “Have sold y number of cars in this year as per our plan”

There may be several answers for the questions above depending on the goal you may set. But I guess you get the idea.

As you can see, setting the goals and cascading them down one step is hard enough. How about cascading your goals to thousands of employees. It will not be easy. But this is where Hoshin Kanri comes to play.

Hoshin Kanri is a very important tool used in lean environment. It is known as a good policy deployment tool. It basically systemizes the process of passing information level by level so that all the components of your organization would be completely aligned to the overall goals of your organization.

Every department will have their objective set by the Hoshin plan for their organization. Every sub divisions of the department will have their objectives set based on the goals their departments need to achieve. It will cascade down to the employee, and will clearly tell your employee what he or she has to do in order to achieve the goals of your organization. Isn't this cool?

Again it needs to be said however, this process is not easy either. It requires mindset changes, thorough follow up and dedication. No one is 100% in this regard. But there is no need to be 100% in your hoshin efforts to realize its benefits. You may realize it on the go.

Collected by: Md. Tarikul Islam Jony
Mail:jonytex073@gmail.com
+8801912885383

Lean Manufacturing tools series 19 (Six Sigma)

 Six sigma is the strategy concerned with reducing the amount of variation concerned with completing a process on a repeated basis, so that the overall product can function at a level that is acceptable to the customer. It is also the practice of constant improvement by identifying defects that can be brought under control in order to improve the functionality of the end product. While it may seem like six sigma is a highly technical skill, in reality it is used in many different sectors. It is not uncommon to see six sigma practices implemented into marketing, sales, and customer support organizations as well.

 Initially created and implemented by Motorola, most companies have implemented some sort of version of a six sigma program in most of their departments. There are some companies that even require all personnel to be trained in six sigma implementations and policies. It uses statistical methods integrated with quality and lean processes to measure the possible and recognized improvement in the process. If implemented properly, entire teams and sub organizational structures (i.e. black belts, green belts, etc) are implemented to guide personnel in the proper conduct of the six sigma process and bringing the culture to the workplace successfully. 

The idea behind six sigma is revealed in the name of the process… through identification of sources of variation and cost, teams are formed to find what the sources are, and then the variation is measured and plotted. It is then analyzed to see if there are other, uncontrollable aspects of the data that may be effecting the way that the parameter is measured.

 All of these are taken into consideration, and then the corrective action that is supposed to bring the process to within six sigma of the target value is implemented, or in other words, the process is improved. Over time, the process is conducted with the corrective action in place, and the parameter, once again, is measured. 

This measurement is plotted, just as it was prior to the corrective action implementation, and the corrective action is analyzed for its effectiveness. The team then discusses what actions can be implemented to ensure the quality improvements are maintained and the progress is not lost by a lack of control over the corrective action. 

The beauty of six sigma is that it can be used in any application, in any business, at any time. As stated before, there are plenty of documented case studies that show how six sigma can be effectively used inside of everything from sales and marketing to very complex manufacturing procedures. With the proper training and teams in place, the sky is the limit with regards to the amount of improvement an organization can realize by implementing the six sigma infrastructure.

 

                          Figure 1

As can be seen in Figure (1), there are five basic steps to completing a six sigma project. The first is “Define”, in which the parameter in that will be the focus of the project is identified. Additionally, the impact to the bottom line of the business is discussed and the potential savings is measured. It is at this point in which the company will decide whether or not to pursue further action in the improvement of the parameter, and whether the time and funding spent toward the improvement will pay off in the end. 

Next, the parameter is measured in the “Measure” phase. Statistic relevance is taken into consideration as well as other sources of variation such as gage error. It is determined how well the actual parameter can be brought under control by measuring it with respect to the sigma value of a normally distributed curve. 

Take, for example, a process that has 1000 opportunities for a defect. Of these opportunities, 2 defects emerge. This obviously means the process has .002 DPO, or defects per opportunity. From that, we can figure out what our DPMO, or defects per million opportunities. To do this, we simply multiply the DPO x 1 million. Our process has a level of 2,000 DPMO. This means that for every million pieces of this product we produce, 2,000 of them will be defective.

From the DPMO and our DPMO/σ table, we find that our σ value is 4.37. By looking at Figure (2), you can interpret this to mean that you will have a 99.73% chance of having between 1,987 (-3σ) and 2,014 (+3 σ) defects for every 1,000,000 parts produced.

 

 

                                           Figure (2)

Once this is completed, the team comes together and analyzes the data in the “Analyze” phase. If the previous two phases were correctly conducted, it will show where the greatest room for improvement exists, and the corrective actions are identified with the estimated improvement calculated.

Improvement is measured after the corrective action is implemented in the “Improve” phase. This phase is almost identical to the “Measure” phase, but more strong influence is placed on the corrective action‟s impact on the final parameter variations.

Finally, the last stage is “Control”, in which the corrective action is either modified or changed such that a long term realization of improvement is shown. Many times the corrective action is temporary in nature and must be modified to be able to sustain the improvement.

While anyone can be taught to brainstorm and start six sigma projects, it should be noted that without a focused and well trained team, there is a very large possibility for failure inside of the six sigma project. It is recommended that a dedicated team be placed in charge of every project and assist the champion in making the project run smoothly.

Six sigma has been proven to set companies apart from each other with its effectiveness. It is practiced in almost every major corporation and almost always results in a better, leaner, and more proficient company.

Prepared by:Md. Tarikul Islam Jony
Mail:jonytex073@gmail.com
+8801912885383