INDUSTRIAL ENGINEERING: Industrial Engineering

Showing posts with label Industrial Engineering. Show all posts

Thursday, August 28, 2014

Useful Formulas for Industrial Engineers

12 Useful Formulas for Industrial Engineers (Poster)

I love formulas for mathematical calculations. Because a formula helps me getting the result quicker and it specifically mentions what all data I need to collect to find result of the desired thing.

In garment manufacturing, industrial engineers, production managers and planners measure factory performance on daily basis. Performances are measured using standard formulas. I guess you are already using such formulas for calculating performance.

Don't you think, it would be a good idea to have a poster of commonly used formulas in your work space? A poster is very useful tool for many reasons. I have made one poster for you and sharing it with you.

Following are the common formulas those are used by garment industry professionals.

Formula#1:

Daily Line Target = (Total working minutes in a day X No. of operators in a line X Line eff%)/Garment SAM

Formula#2:

Individual operator target = (Total working minutes in a day X line efficiency %)/Operation SAM

Formula#3:

Individual operator Efficiency% = (units produced X operation SAM X 100)/Total minutes worked

While you are developing skill matrix for sewing operators, you need measure individual performance. Secondly, if you plan to start performance based incentive scheme for individual operator, measuring individual operator efficiency is essential.

Formula#4:

Line Efficiency% = (Line output X garment SAM X 100)/(Number of operators X minute worked in day)

Note: include helpers and worker doing manual operations in case you have included SAM of those operations.

Formula#5:

Machine Productivity: Line output / No. of machine used

Machine productivity is measured in production per machine per shift day.

Formula#6:

Labor Productivity = Line output / No. of total manpower (operators +helpers)

Formula#7:

Line WIP (work in process) = Total pieces lie on the line for a particular order line
WIP of the line of an order is equal to Total pieces loaded till date minus Total piece out till date.

Formula#8:

Standard Time = (Observed time X observed rating) + Allowances

Allowances – Relaxation allowance, contingency allowance

Formula#9:

Machine utilization% = (Actual Machine running Time X 100) / Time available

Formula#10:

Cost per minute = Total cost incurred in labor / Total available working minute in a day X no. of labors

Formula#11:

Production Cost pet unit = Total cost incurred in production in a day/ no. of garment produced in a day

Formula#12:

Man to Machine ratio = Total manpower of the factory / Total no. of sewing machines (utilized)

Poster: 12 useful performance measuring formulas (Click to enlarge the image).

suitable for printing and hanging near your work space when you need to see it most.

Note: Our purpose is to provide you correct information. Still if you find any formula that is not correct you may comment in the below comment box.

Application of Industrial Engineering

Application of Industrial Engineering in Garment Industry

Many articles have been written and published on industrial engineering since the inception of this blog. What is the new in this post?

This post is written to explain the application of Industrial Engineering (IE) concepts in garment Industry. To many, this is important to know why one should set up an IE department in garment factory. I have taken help of two questions to explain this topic in detail and also recommended a book at the end of this post for your further reading on this topic. Two questions are -

What is the application of Industrial Engineering in apparel industry?
How Industrial Engineering concepts are used by apparel manufacturers?

What is the application of Industrial Engineering in apparel industry?

Industrial Engineering concepts are used in garment manufacturing to fulfill the following purposes -

Monitoring production floor and having better control over the production floor
Improving processes and improving method of working to increase factory's overall performance and standardized garment manufacturing processes

Overall application of Industrial engineering can be explained better by describing common tasks of the IE department. Coomo tasks of an IE department are as following but not limited to these

Work measurement of sewing operations, cutting room jobs and finishing jobs
Setting standard time for sewing operations and manual operations
Style analysis and conducting research and development (R&D) of the styles
Improving method of work and design workstation
Production planning and factory capacity determination
Work aids development
Work station designing and machine layout planning
Labor cost estimation
Performance measuring of workers
Training of workers (sewing operators)
Designing incentive scheme and calculating incentive for sewing operators
Setting line production target of the sewing lines and chasing production from line supervisors and operators
Application of lean tools

Read full list of job profile of the industrial engineering department in a garment factory.

How Industrial Engineering Concepts are used by apparel manufacturers?

Factories those are using IE techniques mostly have a complete IE set up (department). An IE department consists of an IE managers (in-charge) and Industrial Engineers and juniors engineers. The strength of IE team widely varies based on the maturity level of the department and on the focus of application of Industrial Engineering. Without having enough team members, an IE department can not work effectively.

Industrial Engineers are utilized in the following ways but not limited to those -
Factories apply all or few of the above listed functions to

assist line supervisors by preparing resource requirement plan (machines and equipment and manpower), line setting and line balancing etc.
assist production managers in target planning and production planning,
help merchandiser and marketing personnel by providing labor cost and production lead time,
help HR department by providing operator performance level, and help in operator recruitment
prepare MIS reports and show management team product status on daily basis and alert management team if their attention is needed
set up standards operating procedures for new tasks, new process required for ever changing fashion products

More than the regular jobs, IEs are also responsible for thinking of continuous process improvement. Initiation of new projects and implementation of the project that has been undertaken, showing the improvement opportunity within the factory to management team. Engineers are involved in performance improvement tasks of the cutting department and finishing department.

Companies those have limited manpower in IE team, only involves engineers for routine jobs like, making operation bulletin, thread consumption, preparing daily production reports etc.

Conclusion:

No doubt that Industrial engineering department is adding a lot of values to the company. Without having Industrial Engineering team one would not know how things are going on the shop floor, what corrective measures need to taken on time, effective utilization of manpower and machines.

Industrial engineering concept need to incorporate at the time of plant set up instead of changing and modifying things later after factory starts making garments.

Applications of IE tools are also explained in other articles. Check our archive page of industrial engineering articles. You can also refer the free eBook 'Industrial Engineering 101' on which you will get the full list of industrial engineering topics. Details of the topics are available in this site. You can read those articles by clicking on the topic.

To increase your knowledge on Industrial Engineering subject and production management irrespective of industry, I recommend you to read this book. In India you can also buy this book from flipkart.

Meaning of SAM in Garment Industry

What is the Meaning of SAM in Garment Industry?

As defined in the book Introduction to Work Study, ILO,

SAM is the time value arrived at for a task based on the average rate of output which qualified workers will naturally achieve without over exertion provided that they know and adhere to the specified method and provided that they are motivated to apply themselves to their work.

Here SAM stands for Standard Allowed Minute.

In garment industry, specifically in production SAM is used for measuring work. In the factory work study department (also know as Industrial Engineering department) measure and calculate SAM for sewing operation using standard calculation method. Read 'How to calculate SAM of the garment'

SAM is used many ways directly and indirectly. Some of those are

Factory as well as individual operator performance is measured by means of SAM
Labor cost and associated cost ratios are measured by SAM
Operators payroll and incentive amount is calculated based on earned SAM
Latest production scheduling systems like line balancing system and performance measuring systems use SAM as one of the primary parameters.

An organised garment manufacturing company can not think about managing and controlling shop floor without using SAM of the garment and individual operations. Even apparel buyers do negotiation of garment manufacturing price based on garment SAM.

To derive most appropriate SAM value of a garment, factories use PTS based systems. Standard Time is also derived from time study method.

Thread Consumption

Thread Consumption Calculation Process for Garments is Simplified

Calculating Thread Consumption of a garment is one of the common processes in garment manufacturing. It was never an easy task to find average thread requirement for a style in bulk production. First reason, this is a time consuming process. Secondly, though factories use scientific method for calculating thread average, most of the time factories source extra threads for production or factories found lot of leftover threads after style completion.

However, you need to follow the process everyday. When you get a new style, extra time needed to understand the operations (construction details). One other important point I like to mention that till date providing thread average is a job of a production guy or an Industrial Engineers.

Thread manufacturing company American & Efird (A&E) has simplified thread average calculation process by introducing ANECALC. Now anybody, who knows about garment operations, machine types to be used to make the garment in each operation, can calculate the average threads requirement for the garment by using ANECALC.

Thread Consumption Calculator by A&E

ANECALC is an MS Excel based thread average calculation sheet. A&E made Thread Consumption Sheet for most of the apparel products (See below). List of operations of the those products are already written in the calculation sheet. Formula are added into the sheet. Most of the required information are pre-filled. You just need to modify values where needed. If required you can add or discard operations on the sheet. Instruction of using the ANECALC sheet (New Help Guide) is there in a separate worksheet of the same file.

Men’s Neck Tie
Missy’s Long Sleeve Knit Shirt
Missy’s Knit Shirt
Missy’s Knit Dress
Missy’s Henley Shirt
Missy’s 5 Pocket Jeans
Men’s Work Shirt
Men’s Work Pants
Men’s Work Coverall
Men’s T-Shirt
Men’s Tank Top
Men’s Suit Trouser
Men’s Suit Coat
Men’s Short Sleeve Polo Shirt
Men’s Long Sleeve Polo Shirt
Men’s Long Sleeve Mock Stretch Knit Shirt
Men’s Protective Clothing- Long Sleeve Shirt
Men’s Protective Clothing- Pants
Men’s Protective Clothing- Coverall
Men’s Thermal Underwear
Men’s Knit Brief
Men’s Hockey Jersey
Men’s Gym Shorts
Men’s Fleece Sweatshirt
Men’s Dress Slacks
Men’s Dress Shirt – Short Sleeve
Men’s Dress Shirt, Long Sleeve
Men’s Chino Pants
Men’s Casual Woven Shirt
Men’s Carpenter Jean
Men’s Boxer Shorts
Men’s Blazer
Men’s Athletic Jacket
Men’s 5 Pocket Jean
Kid’s T-Shirt, Long Sleeve, Crew Neck
Kid’s Tank Top – Size 4
Application Guidelines: Kid’s Polo Shirt
Kid’s Knit Shirt
Junior’s Fancy 5 Pocket Jean
Girl’s Henley Shirt
Boy’s Jean
Boy’s Carpenter Jean
Baseball Cap
Ladies Panties
Ladies Tank Top
Ladies Swimsuit
Ladies Jeans
Ladies Bra – Petite
Ladies Bikini
and More ...

Download the excel sheet for the specific product and start calculating average thread consumption.
If you find this article helpful, you can share this with your friends.

How I Learned Industrial Engineering

How I Learned Industrial Engineering (and How You Can Too)?

For last 3 years I'm writing tutorials on Industrial Engineering topics ... and I learned many things on Industrial Engineering in this process. How did I learn that much of Industrial Engineering?

In this post I will share methods that I used to learn (and still using) Industrial Engineering and how you can too learn it. These are non-traditional learning methods but very effective. You can copy my techniques and learn Industrial Engineering.

Learning by doing:

I don't have an Industrial Engineering degree. Whatever I know and learned about Industrial Engineering is by doing it myself. I read Industrial Engineering topics in college. I had seen many IEs to practice Industrial Engineering methods and to use IE tools in factories during my Internship and Graduation Project. When I was heading the Production Planning Department in an export house, I used to implement basic Industrial Engineering tools in the factory. I did many mistakes initially but I learned from my mistakes.

So you can too learn Industrial Engineering by doing and practicing it on the floor. While doing something first time, you might make mistakes. That is the way to learn things. Keep it up. I learned production planning and merchandising also by doing it.

Learning by teaching others:

I love to teach learners. Earlier I used teach my subordinates. When I was consultant I taught many participants from client companies. When I teach others I learn many things in the teaching process. You might read IE tutorials (articles) in OCS. Do you know how I learned all those topics? All because of OCS readers who force me to learn, so that I can teach them later and can write new tutorials. I get questions on various topics from OCS readers. I prepare the answers and when I prepare answer for a particular question, I need to research and read the topic first. Thus I learn it.

To learn IE you can too start teaching your subordinates or juniors. You don't need to be master in your subject to teach others. Whatever you know more than others you can start teaching with that only. When you start teaching, you will be asked questions by your students. It is not necessary that you have to know all answers. If get chance you can learn the answer of the question and answer to your students. If don't find your student start teaching others from production department.

If nobody asks you question, head over to OCS Forum and give answer to the questions that are posted there by other members.

Learning by asking questions:

This is the easiest way of learning something. When I meet with Industrial Engineers in export houses I ask different types of questions to them for clarification. I get answers for most of the questions, as they are working on this field for many years they know the answer. You can also start asking question to your seniors, when you need to know something. If you don't have senior or experienced colleague, you are welcome to send your questions to me or post your questions to the OCS Forum.

Reading articles online and/or off line:

I read articles on magazines or in the Internet daily. I learn many things by reading and also discover new areas of learning by reading. My reading topics are not limited to apparel production and Industrial engineering only. I read various topics to get ideas.

You can also start reading technical magazines related to Apparel Production Management and Industrial Engineering. If you don’t like to spend money on print magazines, read free articles on the Internet. By reading articles on Industrial Engineering you can increase your knowledge and you can teach others a new topic.

Discussing topics with your colleagues and seniors:

This is a great way of learning. Currently I don't have Industrial Engineering colleague. But I spent 2 and half years with a group of IEs. That time we had lot of discussion on Industrial Engineering. Still I practice this process of learning. As I said I regularly visit garment export houses. When I meet with factory IEs, we discuss things whatever we find interesting, within IE or out of IE topics.

Watching videos on YouTube:

YouTube is a great source for learning by watching videos. You will find numerous videos on sewing operations for different products, semi automatic and fully automatic sewing machines, and different types of material handling equipment. When you watch videos, observe it closely. You can learn many things like, good movements, workstation layout, working speed, machine types, attachment and guides used and many more things.

Conclusion:

There is no end of learning. And nobody can improve his/her performance continuously without learning. I have explained above how to learn Industrial Engineering. But these techniques are applicable to anything you like to learn.

Calculate Production Target and Worker’s Bonus on Initial Days of Production Start

How to Calculate Production Target and Worker’s Bonus on Initial Days of Production Start?

Question

Many of my orders are of 5,000- 22,000 pieces per style. My sewing line's output is around 1,200 pieces per day. So styles are finished within 1 -2 weeks and need to change style. In the first week of loading a style operators are not familiar with style and they learn in this period. So the time measurement is not correct to be a reference. Then in second week reference can be measured accurately but almost the styles get finished.

How can I set the target and bonus more adequate in this situation? Bonus amount should be attractive to workers and also fair to factory. Workers work on hourly wage.

Answer

The problem raised in this question is a fact of garment manufacturing factories. When a new style is loaded to a line, operators learn on initials day and produce less. That is one of the reasons for low production compared to pick production or average daily production.

In this article I will explain how you can set production target and operator bonus effectively even on the initial days of the production start.

Setting Production Target

You might already know the formula that is used to calculate daily production target of a style. If don’t know here it is.

Production Target per day = (Number of operators X Working hours per day X 60 X Line Efficiency%)/ (Product SAM)

There are two problems in using this formula calculating production target on the learning stage.

You wouldn't know actual line efficiency – as efficiency will build up day by day up to pick efficiency level. And without past data you can’t assess what would be the efficiency of day 1, day 2 or day 3.
Product SAM - assuming that you are not using Predetermined Motion Time System (PMTS) for measuring product SAM. Production capacity is estimated based on time study of the production line. This has been indicated in the question.

The only solution of this problem is that you have to develop database for line efficiency at the learning stage. This period is called as learning curve. Develop learning curve of your lines (style wise, order wise) by studying styles. Measure the trend - how production build up happen and reach to pick production day by day at the learning stage. Once you have enough data on efficiency build up (learning curve) you can make target plan for the future orders. Learning curve may vary depending on order quantity and style difficulty level.

Learning curve (Efficiency% Vs Days) of a typical garment factory for one style is shown in the following Fig. In this learning curve day wise efficiency build up is shown.

Figure: Learning Curve

Similarly develop database for standard time for your styles by using Time Study method.

Now you have both data to calculate production target even at the learning stage. Practice it and write me if find any issue in using the above method.

How to Set Worker Bonus?

You can set workers performance bonus at the learning stage for individual worker or/and for the group without much difficulty. It is the similar method that you use calculating bonus amount on the normal production days. The difference is - in this period the target efficiency% for becoming eligible for earning bonus to be kept lower than normal production. Design day wise target efficiency based on your learning curve. You can keep the bonus amount per point increment of efficiency same. Or slightly more to motivate your operators working harder.

Tools and Equipment used by Industrial Engineers

Tools and Equipment used by Industrial Engineers in the Garment Industry

In their day to day job, Industrial Engineers (IE) use various type of tools and equipment. What all equipment and tools to use, depend on the job responsibilities of an IE in a company. Name of the common tools and equipment are listed below. Purposes of the tools are also mentioned here.

Stop Watch (Digital or analog): Measuring observed time at the time of Time Study.

Measuring Tape: Measuring length of seams and measuring distances

Picture (Clock wise direction): Digital Camera, Digital Stop
Watch, Digital Tachometer, Measuring tape

Digital Camera: Capturing videos for various operations that help in motion analysis of operations.

Tripod for the camera: Used as camera stand.

Time Study board: Required during time study to hold the Time Study format.

Calculator: Data calculation and report making.

Tachometer: to measure speed of the motor of sewing machine. This equipment is use to find machine rpm.

Data capturing and process analysis formats: For example- Time Study format, Motion analysis format etc. Data capturing and analysis to bring improvement.

Various documents: Documents are used to assist production and other processes with information, methodology or layout. Formats are like Operation Bulletin, Line Layout, Pitch Diagram, Hourly report format etc.

Computer: Data analysis, Report making, Mailing, video analysis of operations etc.

Standard Hours Earned in Garment Manufacturing

What is Standard Hours Earned in Garment Manufacturing?

Standard Hours Earned term is not much known in garment factories. Here, Work Study officers or Industrial Engineers working in garment manufacturing factories (Export house or domestic garment manufacturing) don't use 'Standard Hours Earned' instead engineers use Standard Minutes produced or Standard Minutes earned. So when we heard this term first time, we think it might be a different measure.

Let me explain what does ‘Standard Hours Earned’ mean.

This is similar to Standard Minute Produced by workers. Instead of minutes it is presented in hours. To get Standard hours earned value, standard minutes are divided by 60. Like, if an operator works for 8 hours a day and produce garment equivalent to 360 minutes then operator’s standard hours earned would be 6 hours (This is derived from: 360 minutes/60).

Formula for calculating standard hours earned:

Standard hours Earned = (SAM of operation X Garments produced)/60

This term is also called as Earned Hours because operator has earned that many hours by his/her effort.

Benefit of using Standard Earned Hours

- Easy to compare produced hours against available hours in a day (efficiency)

- Secondly calculating earning amount (in Dollar) of an operator from earning hours is easy as you know standard hourly rate of your operators.

Also See: How to Calculate Standard Hours Earned, Operator Efficiency and Labour Cost?

Wednesday, August 27, 2014

Workstation Design for Trouser Side Seam Operation

Workstation Design for Trouser Side Seam Operation with Zippy Edge Guide

Attachments are time saving equipment for many sewing operations. Sewing workstation layout can be improved by using attachment and guides.

If you are already using attachments in sewing operations you might know how attachments help in increasing productivity and consistency in stitch quality. I am sharing one such sewing machine attachment used in trouser side seam operations.

Factories those make trousers must see this video. From this video you can follow its workstation layout - like placement of stacking cut panels, height of bench where cutting are stacked. In this video operator is using zippy guide and auto-stacker for stacking stitched trousers. Look at the sewing speed and material handling of the operator. You can use this video to train your operators also.

Video: Side Seam Workstation with Zippy Edge-Guide (Source: Youtube)

If you come across such good videos share it with us.
Or if you are using sewing machine attachments that helped you increasing production please share that.

Also Read: Work aids and Equipment for Garment Manufacturing Industry