Application of Industrial Engineering in Sewing Floor

Introduction:

Industrial Engineering integrates knowledge and skills from several fields of science: From the Technical Sciences, Economic Sciences as well as Human Science – all these can also be supported with skills in Information Sciences. The Industrial Engineer comprehends knowledge in those sciences in order to increase the productivity of processes, achieve quality products and assures Labor safety. Present techno economic scenario is marked by increasing competition in almost every sector of economy. The expectation of the customers are on the rise and manufacturers have to design, and produce goods in as many variety as possible (concept of economics of scale is no more talked off) to cater to the demands of the customers. Thus there is a challenge before the industries to manufacture goods of right quality and quantity and at right time and at minimum cost for their survival and growth. This demands the increase in productive efficiency of the organization. Industrial Engineering is going to play a pivotal role in increasing productivity. Various industrial engineering techniques are used to analyze and improve the work method, to eliminate waste and proper allocation and utilization of resources.

Industrial Engineering

In Normal word, Industrial Engineering integrates people, technology, and information to enhance a globally competing enterprise. This definition of Industrial Engineering has been recently developed to more accurately reflect the new global economy. Integration refers to the ability to understand the need for looking at broader system and scope and not focus on individual problems. Most engineering disciplines fail to do this.

American Institute of Industrial Engineers (AIIE) defines Industrial Engineering as follows: “Industrial Engineering is concerned with the design, improvement and installation of integrated system of men, materials and equipment. It draws upon specialized knowledge and skills in the mathematical, physical sciences together with the principles and methods of engineering analysis and design to specify predict and evaluate the results to be obtained from such system”.

 Common characteristics of an Industrial Engineering include:

• Inquisitive mind

• Negotiation skills

• Listening skills

• Creative problem solving

• Diplomacy

• Patience

• Ability to adapt to many environments and interact with a diverse group of individuals

• Good common sense

• Continuous desire to learn

• Leadership skills

• Resourcefulness

• Desire for organization and efficiency

• Good math skills

• Strong time management skills

• Mechanical aptitude

• Excellent communication/salesmanship

• Quantitative skills

• Technical competency

• Continuous drive for improvement

• Passion for improvement

 Working area of IE:

  • Most in Manufacturing, such as:-
  • Plant Engineering
  • Manufacturing Engineering
  • Quality Engineering
  • Process Engineering
  • Methods Improvement and many more

EFFICIENCY IMPROVEMENT TECHNIQUES OF INDUSTRIAL ENGINEERING:

1. Process Analysis

2. Operation Analysis

3. Time study

4. Value engineering

5. Statistical quality control

6. Statistical inventory control and ABC Classification Based Inventory Sytems

7. Six sigma

8. Operations research

9. Variety reduction

10. Standardization

11. Incentive schemes

12. Waste reduction or elimination

13. Activity based management

14. Business process improvement

15. Fatigue analysis and reduction

16. Engineering economy analysis

17. Learning effect capture and continuous improvement (Kaizen, Quality circles and suggestion schemes)

18. Standard costing

19. 5S

Many classes relate to following topics:

  • Quality Control
  • Manufacturing Processes
  • Plant Layout/Material Handling
  • Engineering Economy/Cost Estimating
  • Time Studies/ Labor Cost
  • Human Factors/ Safety
  • Simulation/ Statistics, and many others

Working field of IE

At problem identification/definition stage following steps must be taken:

  • All the facts about the operation are collected and recorded using various recording techniques like charts, diagrams or models.
  • Critical Examination of all facts by asking series of questions.
  • Alternative ways are found by techniques like brainstorming.
  • Based upon the criteria fixed for evaluation, the best alternative is selected.

Industrial Engineering in Garments:

A. Apparel Engineering:

The two steps of finding the best way to do a job and then timing to find out how long it takes are referred to as Motion Study and Time Study. Engineers are taught to do the Motion Study first, as any time study data on incorrect motions is not of much value. Some uses of Apparel Engineering are:

i. Quotas and piece rates

ii. Costing: By knowing how long it takes to perform a job, the total time and cost for manufacturing a product can be determined. Determine sales price.

iii. Manpower Planning: By knowing how many units one person can produce it can be determined how many people are needed to produce a given volume.

iv. Machine Requirements: The number of machines required can be determined by knowing the output from one machine.

v. Production Planning: Time study enables us to measure the capacity of a plant to produce. Decision as to how much volume to load into a plant can be made.

These are only a few of the common uses of Motion and Time Study. As we can now see, the information obtained is useful far beyond just setting quotas and piece rates. As we have already mentioned, Motion and Time Study is the most common function associated with an apparel engineer. But what are some of his other duties? Let’s list some of the other things we might find an apparel engineer doing:

  • Plant Layout: The location of machines and equipment to provide the best work flow.
  • Production Flow System: Determine the best way to move work from job to job (individual pieces, tied bundles, on trucks, etc.)
  • Machines and Attachments: What machines are the best for a given job? What attachments simplify the job?
  • Pay Systems: Deciding the best way to pay people for their work effort. (Straight time, piecework, split incentive, group incentive, straight time bonus, etc.)
  • Operator Performance: Responsibility for operators achieving expected performance levels.
  • Operator Training: Responsibility for program of training new employees.
  • Production Control System: Design system of measuring and controlling production flow through plant.
  • Cutting Room: Engineering jobs in cutting room for incentive plan. Also might include program to increase material utilization.
  • Quality Control: Design program to measure and control quality of workmanship in plant.
  • Distribution: Engineer warehouse and shipping facilities.
  • Payroll System: Design payroll procedure to handle pay system and generate necessary cost reports.
  • Others: Plant safety, maintenance, supplies.

B. The Benefits of Engineering:

i. Work Simplification

One of the main benefits of almost any engineering effort is that it makes work simpler to perform. This holds true for operators, supervisors, and top management. When an engineer analyses any area of work, he does so with the thought in mind. Do not be misled about into thinking, however, that work simplification means people always will be doing less work. They may, in fact, do more work but within the same amount of time as before. Because work has been simplified, people’s ability to produce is increased.

ii. Increased Productivity

The ability to produce more within the same amount of time is a company’s insurance for survival. This ability means that the company can now accept more work. It means that costs can be lowered by avoiding overtime. It means that fixed costs can be spread out over more units of production. It means that profits Improve.

iii. Increased Profits

When a company’s profits increase, everyone involved is in a better position. Owners and stockholders prosper. Management and supervision are rewarded for their performance. Money is available to do more for the operators. A company is able to expand which creates more Jobs.

iv. Increased Earnings

Most engineering projects not only increase company profits, but also result in higher earnings for employees. Most companies are willing, and in fact eager, to share with its employees the financial gains that are available through engineering.

 

C. Application of IE

The roles and responsibilities of the industrial engineering department are not just limited to timing operators and making operation bulletins as it is only a part of the job. The I.E function can contribute significantly to improvement in working and productivity of almost all the departments of apparel manufacturing. Let us discuss few of the activities of various sections of apparel manufacturing which can be associated with industrial engineering:

1. Merchandising

In merchandising section the Industrial engineer can work closely in following: a) Product Analysis-

  • Determine the optimum method of construction to achieve required finished product efficiently.
  • Establish the operation sequence (Operation bulletin).
  • Specify the equipment type and work aids to be used. b) Costing-
  • The first stage is to calculate the SMV of the garment.
  • To calculate the production cost for that particular garment by multiplying the total SMV of the garment with the average cost incurred by the factory to produce one SMV.

2. Production Planning

Production planning is defined as, “the technique of foreseeing or picturing ahead, every step in a long series of separate operations, each step to be taken in the right place, of the right degree and at the right time, and each operation to be done at maximum efficiency.” Production planning provide a line for effective, balanced flow of product, incorporating line and individual (operation) productivity standards.

  • Plant capacity can be calculated by I.E dept so that planning can book order as per the available capacity.
  • I.E can assist in better planning by helping in better style allocation to different units or lines.
  • I.E can formulate an efficiency/performance build-up for a particular style based upon the work content or past performance. This can inform the planning dept that a particular line will take how many days to produce a specific quantity of a style. This will help the planning dept to plan the availability of resources and material in advance.

3. Production

Industrial engineering is a key part of a production process. One of the basic functions of engineering is to get facts. These facts may be in form of a time study, the engineer has made or cost report the engineer has designed. So we can say that the basic need for engineering is the need for management information.

4. Maintenance

Proper maintenance leads to better capacity utilization of same asset, avoiding thus the investment in addition facilities. So far industries have a tendency to neglect maintenance function, thinking it be a not so important job, however necessary.

5. Quality

Quality is an asset, which may be offered to the potential customer of a product. There are two aspects of quality, which contribute to the ultimate quality of the product. Quality of design is the first aspect, which depends on the type of materials used, specs specified by the buyer, method of production, knowledge of the design and skill level of the person. The degree to which this quality is achieved in production that is the quality of conformance is the second aspect.

6. Human Resource

a) Manpower Planning- I.E can calculate the manpower required to perform a specific job at a certain performance level.

The manpower can also be calculated as per the capacity of the plant using standard ratios like Man to Machine ratio. The number of people for a factory having x number of machines can be fixed through this ratio (South Asia standard is 1.8: 1).

b) Skill Matrix- Skill matrix refers to the database of available worker skill in the factory. The workers‟ skill is analyzed on different jobs and based upon his/her performance on a particular job a grade is given. This grade defines the level of performance that operator can achieve on that specific job.

This matrix is used in 2 ways:

While allocating workers to a job as per the skill requirement of that job.

To analyze the skill availability and distribution throughout the factory. This can be compared with the skill requirement for a particular time period and shortage/excess skill availability to achieve at the training requirement.

c) Performance Measurement- For measuring the performance of any individual first step is to define the targets and second step is to develop performance measuring tools. An industrial engineer can help in setting up of measurable goals and targets, which could be time standards for an operator and key performance indicators for middle & senior management.

d) Training- Industrial engineering should be responsible of working on a scientific recruitment methodology for workers so as to check the basic skills are already present in the selected personnel. The training methodology for these trainees should target towards efficient and rapid learning with proper control tools in place.

7. Production Follow up

“Follow up” means that someone “checks and Stays with” something until the desired results have been achieved. Many worthwhile plans and projects have failed because someone did not follow up. So for the purposes of this training follow up means to stay on top of something until the desired results are achieved.”

Uses of operator follow up:

There are a number of uses for operator follow up:

a) Improve Performance (Motivate)-

In many cases, operators are not producing as much as they can. They have no particular problems, but are just not giving, it the effort to be a 100 percent operator. Follow-up in this case is a matter of motivation. The person doing the follow up should not only show the operator that she can do well, but should also make her want to continue to do well. Most people who are capable will perform well under follow up. And once they have performed well for several days or a week (or maybe more) they get used to this type of performance (and earnings) and then tend to stay there.

b) Prove Job Quotas-

Perhaps the most common use of follow up (at least by engineers) is to prove a new quota. In other words, the quota will be proved if the operator performs well when compared to the new quota. Very often operators have a psychological resistance to change. It is essential to get the operators to overcome this psychological barrier, and that can be done through follow up and showing the operators that changes can be made satisfactorily.

c) Spot Troubles-

Occasionally, there seems to be no logical explanation as to why an operator is not performing. Follow up in this case can uncover problems that need to be solved such as machine delay, work flow, small bundles, too much personal time, etc.

WORK STUDY

Work study is the analysis of the operations required to produce a style. Effective work study requires both methods analysis and work measurement. Methods are studied, analyzed, and the elements of the method measured in terms of time consumed. Data are collected, analyzed and used to support decisions on rates and methods. Work study is also important to ergonomic decisions, job design, and work station development. Decisions must be based on extensive study and documentation that is developed with work measurement procedures. Unsubstantial opinions are not sufficient justification for change.

OBJECTIVE OF WORK STUDY

– Explain mechanization and automation relative to general- and special-purpose machines
– Examine the basic components of sewing machines and work aids
– discuss the effect of equipment on product quality and performance.

–      Efficient use of human efforts.

–      Measurement of work values.

–      Set standards for labor cost control.

–      Initiate & maintain incentive bonus schemes

–      To standardize material and machines used

–      Determine the time required by an ideal operator to perform the task with efficiency.

BASIC TERMINOLOGY OF WORK STUDY

Capacity: Productive capability (output) of a plant. Machine or work center in a given period of time.

Created from: machine, time, space, capital, labor Frequently measured in units of Output (no. of garments) May be expressed in terms of input (no. of hours)

Maximum Capacity: Total hours available under normal conditions for a given period of time

Efficiency Factor: A factor used to adjust the maximum capacity to a realistic level of potential production capacity.

Efficiency = Standard minutes earned /Actual minutes attended.

Realistically 90% is the efficiency factor for all the firms attributed to Down Time, Supervisor, intervention, absenteeism, and other demands in a work day.

Down Time: The period of time that a machine is not operational because of setup, making adjustments, maintenance or mechanical failure.

Potential Capacity: Maximum capacity adjusted for efficiency

Committed Capacity: Total of hours previously allocated for production during a given time period, ensures the plant of a continuous flow of work employment. It affects potential start and completion dates of the succeeding orders.

Available Capacity: The difference between Potential Capacity and Committed Capacity for a given period. This is used to estimate deliveries on new orders.

Required Capacity: Standard Allowed Hours/Minutes (SAH’s /SAM’s) necessary to produce a specified volume in a certain period of time.

Excess Capacity: Difference between required capacity and potential capacity.

Work Study can be best expressed in the following manner:

WORK STUDY
1. METHOD STUDY
Record to Compare
Seek best method
2. WORK MEASUREMENT
Time Study
Synthetics

In a crux: “Methods are developed and rate set for each operation”

Diagram of Work study:

STEPS INVOLVED: 
1. Analyze each style to determine its requirement for production.

2. Style Analysis is based on:
-Firm’s quality standards
-Amount of labor required
-Available equipment
-Volume to be produced
-Expected “throughput time”

3. Style requirements are determined through analysis of samples and specifications

4. Apparel Engineers are concerned with:

      -Number, complexity and sequence of Operations

      -Equipment Required

      -Time and Skill Required

5. Operation Breakdown: Work in each style is broken down into operations
An operation B/down is sequential list of all the operations that involved in assembling a garment used to establish the workflow for each style.

6. Apparel engineers study each operation to improve its effectiveness and efficiency and to establish methods to ensure a consistent performance by operators and consistent products.

Method Study:

Method study is the systematic recording and critical examination of production, service and business processes in order to make improvements. Method study is also known as methods engineering.

The technique that subjects each operation of a given piece of work to close analysis to eliminate every unnecessary element or operation and to approach the quickest and best method of performing each necessary element or operation. It includes the improvement and standardization of methods, equipment, and working conditions: operator training; the determination of standard time; and occasionally devising and administering various incentive plans.
This definition, however, tends to define methods engineering rather narrowly. It states that methods engineering is limited to operations or pieces of work, but recently the trend has been to address broader areas, such as production processes, the factory in total, or large scale work systems that involve a lot of people and extensive equipment.

Technique of Method Study:

  1. Selection of job to be studied.
  2. Collection, recording and presentation of necessary information.
  3. Analysis of existing methods.
  4. Develop the new method.
  5. Install the new method.
  6. Maintain the new method.

The basic approach for the method study:

1. SELECT

2. RECORD

3. EXAMINE

4. DEVELOP

5. EVALUATE

6. DEFINE

7. INSTALL

8. MAINTAIN

Brief explanation of the eight steps

1. SELECT

The process to be studied to selected and its boundaries are to be defined

2. RECORD

The process is to be recorded in specified charts and diagrams.

  • Process charts
  • Flow charts
  • Flow diagram
  • String diagram

A variety of techniques for analysis and charting have for a long time been established as IE techniques. Among the methods of analysis, process analysis, operation analysis, motion study, time study, work sampling, and flow analysis are widely used. Similarly, among the charting techniques, process charts, pitch diagrams, multiple activity charts, process charts, and machine sequential charts are used. From among these various techniques, the appropriate one will be chosen, based on the object being analyzed.

3. EXAMINE

A process or method has activities.

The activities are categorized into action activities and idle (inventory) activities.

Action categories are subdivided into i) MAKE READY activities, (ii) Do operations iii) PUT AWAY activities

Each activity is subjected to a series of questions:

A. Purpose

 What is done?

            Why is it done?

What else might be done?

What should be done?

B. Place
Where is it done?
Why is it done there?
Where else might it be done?
Where should it be done?
C. Sequence
When is it done?
Why is done then?
When it might be done?
When should it be done?
D. person
Who does it?
Why does that person do it?
Who else might do it?
Who should do it?
E. Means
How is it done?
Why is it done that way?
How else might it be done?
How should it be done?
These questions in the above sequence must be asked every time a method study is undertaken.  They are the basis of successful method study.

4. DEVELOP

The shortcomings of the present process are brought out by the systematic questioning process that is combined with a knowledge relevant to the process being examined. Industrial may have the knowledge required or may not have the adequate knowledge. They need to have a knowledge library to support their effort as well as access to the experts during the study period. Alternatives to the current activities which have the shortcomings are to be generated during this stage.

5. EVALUATE

Alternatives are to be evaluated at this stage to find their contribution to the efficiency of the process as well as effectiveness.

6. DEFINE

The new method or process suggested has to be put down standard process sheets that are issued to the shop or department.

7. INSTALL
Industrial engineers of methods study persons have to train the operators and their supervisors in the new method and participate in installing the method.

8. MAINTAIN

Industrial engineers have to conduct a periodic review of methods to observe modifications brought into the installed methods by operators and supervisors and if they are beneficial, they have to be made part of standard operating procedure (SOP). If they are not beneficial, supervisors are to be informed of the same to bring the method back to SOP.

Charts for Method Study

Production order and method study are generally displayed in charts.

Process charts

  • It is a diagrammatic representation of sequence or order of operations from start to finish.
  • It uses various symbols to represent multiple activities
  • They are generally not drawn to scale.
  • The symbols are drawn in vertical columns according to their sequence and description is given.

SYMBOLS used in process charts:

  1. It represents a broad category of operations executed during a production process.
  2. Operation occurs when an object changes its properties physically or chemically.
  3. Small alphabets are written inside the circle to denote a specific operation.

      Operation

  1. It represents an inspection during a production process.
  2. The object is examined for its verification with required quality & other characteristic.

Movement

  1. It represents a storage during a production process, protected against unauthorized removal.
  2. Distinction can be made between permanent and temporary storage by writing TS or PS in diagram.

Storage

1. It represents a delay during a production process.

2. It occurs when immediate performance of next planned step cannot be taken.

Delay

Time and Motion Study

Time study is a work measurement technique for recording the time of performing a certain specific job or an element of a job carried under specified conditions, and for analyzing the data so as to obtain the time necessary for an operator to carry it out at a defined rate of performance.

 TIME STUDY EQUIPMENT

To carry out time study, a stop watch, a study board and time study forms are required. Along with the study, some measurements of parts and distances moved by the operator etc. may need to be measured. Appropriate measuring instruments are used for such measurements.

            It is important to take studies on qualified workers when the job is done and is to be done by large number of workers.

            A qualified worker is one who has acquired the skill, knowledge and other attributes to carry out the work in hand to satisfactory standards of quantity, quality and safety. (BSI: Glossary of terms used in management services, BSI 3138 , London 1991).

Purpose:

1. To understand the production capacity of the factory, and to draw up plans for the appropriate target output, suitable range of divided labor and optimum production (Scheduling, personnel planning or equipment planning).

 2. To investigate the level of individual skill.

3. To determine the time value for each work compound under the motion study.

 4. For use as a yardstick in evaluating the purpose.

5. To draw up plants and make estimates for a change of product or for the constructions of a new or additional factory.

 6. To obtain an evaluation standard for receiving planning, using the time study as the basis of the cost estimate and control.

 7. For use as the basis for determining the unit cost of manufacture and the wage rate.

8. For use the basis for introducing a production control system.

STEPS IN MAKING A TIME STUDY

1. Study of standard method.

 2. Recording the operative and the surrounding conditions at the time of study, which may affect the method of carrying the work and thereby time required to do the work.

 3. Recording a complete description of the work as it is being carried out and breaking down the work or operation into elements for individual time determination.

 4. Determination of the sample size.

 5. Measuring and recording the time taken using a stop watch for each element in the operation.

 6. Along with measuring time, the time study person has to assess the effective speed of the operative relative to the rate corresponding to the standard rating.

 7. Do the time study for the required sample size.

8. Extend the observed times to ‘basic times’.

 9. Determining the allowances to be provided.

 10. Determining the ‘standard time’ for the operation.

Notes on time study:

 Be cordial and polite, but do not talk unnecessarily to the operator.

 Do not stand in front of the operator. Stand in a less discomforting position, such as off to the side or in the back.

 Never sit down during a time study!

 Always calculate the time study results immediately after the date gathering.

 Controversy over rating arises from a misunderstanding of what is being rated. An operator‟s output can vary only if:

i. She/he varies his/her pace of work.

ii. Varies his/ her method. Method includes the motion pattern, no. of motions and inters-motional delays.

 When studying, the observer notes the speed at which the operator performs, and compares this mentally with the concept of the standard pace at which an operator would work if motivated to apply herself and is free from fatigue (100% operator).

 The engineer should:

i. Have a mental concept of the 100% operator.

ii. Recognize deviation from the 100% pace and be able to put a relative value onto it.

 Do not confuse smooth, fluid motion with slow motion. Don‟t mistake rhythmic intensity for fast productive motion.

 Machine paced operations or elements should be graded 105% to 115%, depending on the effectiveness of the operator in utilizing the machine cycle to do their job properly.

 Before starting a study the engineer must ensure that he understands the correct motion for the operation, and then checks that the operator is using them. The study should not be taken if the motion pattern is incorrect unless the engineer is prepared to compensate for the incorrect motion in his elemental rating or else assures himself/herself that the discrepancy is insignificant.

 Have the quality supervisor or in-line sampler check the bundle. This ensures that the time standard is not established on an unsatisfactory quality standard.

 Non-representative element times are circled. They may arise because:

i. Inclusion of work not identified by the element (such as changing bobbin).

ii. Faulty operation of some sort.

iii. Missing an element time.

 Allowances are added to the 100% time determined by the time study to give a Standard allowed time which will permit the average operator to earn a satisfactory wage, provided there is no abnormal delay and he/she applies his/ herself to her work.

 Machine delay includes the following:

i. Thread changes.

ii. Bobbin changes (on lockstitch).

iii. Cleaning & oiling machine.

iv. Thread breaks caused by operator, machine & thread.

v. Needle breaks.

vi. Minor adjustments or changes in folders and attachments.

vii. First 15 minutes of machine delay.

 The machine delay factor is applied to the total cycle time. This has the effect of giving a delay allowance on the manipulative elements within a machine cycle such as “pick up garment”. On the average this does not present a problem since the percentage has been developed from actual experience.

 Personal & fatigue allowance covers:

i. Break periods.

ii. Personal needs such as water, rest rooms etc.

iii. Minor conversations.

iv. Factors for loss of pace due to getting tired.

Setting the standard time:

The standard time is the time required to complete one unit of work:

 Under the predetermined working conditions.

 According to the predetermined working conditions.

 By a worker with average skill.

The three factors given here are the working conditions, operation method and the worker’s skill. Of these factors, the worker’s skill in particular has the great influence on the processing time. The individual different in skill result in difference in the processing time. If the possible to mathematically understand the individual differences as a unified level value.

The standard time setting may be used for the following purpose:

1. To improve the accuracy of planning.

 2. To assign in an appropriate manner.

 3. To understand the effect of teaching skills.

 4. To set the direction of efforts aimed at improving skills.

Leveling is a method that allows the individual differences to be understood as a unified level value. Leveling permits the setting of the standard time using numbers called leveling coefficients.

The following shows the related formula.

Standard time= Time measure X (1 + Leveling co-efficient) X (1+ Allowance rate)

Rating:

The concept of „Rating‟ (known in the US as „grading‟) is fundamental in time study. The ability to rate effectively distinguishes a qualified time study practitioner from a novice.

Definitions:

 Rating is the process used by the industrial engineer to: compare the actual performance of the operator with his/her mental concept of normal performance.

The rating is the numerical value used to denote the rate of working. In order to rate there must be a defined level of performance to compare with, an „average‟ level.

Time study professionals apply the concept of Standard Operator Definitions:

 

 

Definitions

A Standard Operator is Fully trained and motivated to perform a defined task (having a defined method) and is, by definition average in terms of his or her work-pace.

Standard Performance is Achieved by a standard operator, as long as working conditions are correct.

In a sewing factory, there is always a need to develop the skills and the stamina of the operators. There is a logical way in which this can be done. We develop skills first and then stamina, but the two cannot be separated.

 We can consider skill to be sound & correct methods once we have the method correct, we can start an effective follow-up.

Review methods used and ensure correct motion pattern is in use.

Is there a difference between potential performance (capacity) and actual performance (achieved).The gap is called is called a Capacity Gap.

What is the reason for the capacity gap?

Bundle handling?

Machine problems?

 Cutting quality?

Repairs (sewing quality)?

Personal time?

 Others

Is there a stamina problem? Can we develop performance gradually day by day?

Performance Development

Capacity Study:

When we make a capacity study on an operator, we are measuring the performance she should attain if she continues to work at the same pace and use the same method as observed during the study. This means that at the end of the study we can say that operator has the capacity to be a 120 percent performer” or whatever performance level the study indicates. What exactly do we mean by capacity? Well, it means the same as capability. It means that the operator is capable of achieving the performance measured by the study.

Capacity Study Making:

The capacity study is a 10-cycle study to estimate an operator’s production ability. If the actual production and capacity are different, then follow up studies should be made. During the capacity study, the operator’s average time per cycle to sew her operation is determined. We then assume the operator works at this pace all day and takes the full amount of lost time (machine delay, personal and fatigue time) provided for in the target. We call the time left, after lost time has been deducted, the available sewing minutes. These are divided by the average time per piece to estimate production. Operators benefit from capacity studies only if you spot wasted motions and make suggestions and corrections. Results of every capacity study should be reviewed with the operator.

A. Allowances:

Allowances are added to the 100% time determined by a time study to give a Standard Time which will provide the average operator to earn a satisfactory wage, provided there is no abnormal incidence of delays and she applies herself to her work. These are also used while estimating an operator’s capacity. Three categories are recognized: –

  • Machine delay.
  • Personal and fatigue.
  • Incentive

B. Machine delay

Delays due to machine stoppage including thread changes, bobbin changes, cleaning and oiling of machine, first 15 minutes of machine delay, thread breaks, needle breaks, minor adjustments or changes in folders, attachments, minor delays caused by attachment etc. The machine delay factor is applied to the total of cyclic elements when the work is largely machining, although not applied to wholly manipulative work such as clipping or turning parts.

C. Personal and fatigue

Some aspects of normal required personal time can be quantified, but fatigue itself cannot be measured. It is also impossible to separate personal and fatigue time because of their inter-relation with one another. This allowance came into being through guesswork and trial based on general use. Personal and fatigue allowance covers break periods, personal needs such as water, rest rooms, minor conversations etc. It should be noted that the machine delay factor is applied to 100% time, and the personal and fatigue time (with the incentive factor added) is applied to this to give the SAM.

General comments:

 Use of your time

Follow-up is not simple clocking of cycles. This does nobody any good. Follow-up time is valuable. While timing a 2.0 SM operation use the time between the breakpoints to:

Look closely at the method

  • Encourage the operator.
  • Time the elements of the job.

How to get effective studies:

Capacity studies record single cycles Without :

  • Bundle handling
  • Thread breaks

Bobbin & color changes

When you conduct a study on a „long‟ cycle operation (say more than one basic minute), you can lose a complete cycle, because of one thread break. You can „save‟ and use much of this time if you have broken the job to suitable elements, then thread breaks would affect only one of the elements. You would still have the remaining cycles which can be used.

Other follow-up tools-

In any situations requiring follow-up support you will need to identify and choose the best approach. The tools described for follow up (capacity study, diagnostic and follow-up study) are not the only ones you can use. Be creative in your follow-up. E.g., use graphs to plot cycle times and actual performance against target. Record the times for the particular elements of a job–plot them to show improvements; record single cycle one at a time and plot them; use visual aids to the full, and always explain the results to the operator.

 

Line Balancing and Bottleneck

Line Balancing:

Line Balancing is to share work, to support in another operation, to shift manpower according to their capacity for equal production in every point.

Necessity of line balancing:

  • To get easily out put.
  • To get best performance of the workers.
  • To ensure of proper use of time & manpower.
  • To follow up the line easily.
  • To give the pressure to workers for optimum out put.
  • To know the line’s potential capacity of the line.
  • To find out the productivity gap%.
  • To take the next step for higher productivity at need the line balancing report.
  • To get higher productivity.

Figure: Variation in each process capacity per hour compare to bench mark target per hour Plotting process wise capacity in a line graph shows the variation of each process from the bench mark target as the upper capacity is 490 pieces per hour where the lower capacity is only 115 pieces per hour compare to the bench

Mark target of 200 pieces. This shows the imbalance situation in the line and bottleneck condition throughout the process of the whole garment making as lots of WIP stations in the line.

Balancing Processes

Balancing method is very essential to make the production flow almost smoother compare to the previous layout. Considering working distance, type of machines and efficiency, workers who have extra time to work after completing their works, have been shared their work to complete the bottleneck processes. Previously identified seven bottleneck processes have been plotted in the left side of the Table . Make and join care label and Back neck elastic tape joint both have been made by lock stitch machine and these have been shared by two lock stitch machine processes. Operator who work in Process no. 7 Neck rib make width, have been worked for 50 minutes per hour in her first process, capacity 217 pieces and then have been worked in the process no. 6 make and join care label for last 10 minutes to make additional 30 pieces for overall capacity of 208 pieces on process no. 6. Similarly Process no. 13.B back neck elastic top have been worked for 35 minutes and rest 25 minutes have been worked on process no. 12 to make total capacity of 216 pieces which was originally 153 pieces shown in Table 2. Process no.14, 25, 20 and 22 have been similarly worked on the process no.16, 23, 24 and 27 for the capacity of 195, 198, 153 and 199 pieces per hour. Process no. 24 churi hem raw edge cut have been suggested an extra floater to use after being shared worked from process no. 20.

Bottleneck in line

  • Worker selection wrong.
  • Wrong works flow / sequence of works.
  • Non balance allocation of elements.
  • Works negligence by workers.
  • Workers absenteeism.
  • Machine disturbances / out of order.
  • Lack of supply.
  • Non serial supplies forward from workers.
  • Color shading.
  • Quality problem.

Way of reducing bottle neck

  • To select right workers for right works.
  • To keep supply available in time.
  • To maintain serial number.
  • Reject garments should not forward.
  • Supply should be forwarded after checking.
  • To alert when bundling (maintain serial number)
  • By improving method.
  • By improving workers performance.
  • By reducing sewing burst
  • To make size set sample minimum 15 to 10 days before input.
  • To arrange pre-production meeting in time.
  • To prepare layout sheet before input in the line.
  • To check fabrics and accessories before issuing in the line.
  • To submit the layout sheet to maintenance section minimum 2-3 days before for better preparation.
  • To check pattern before supply in the line.
  • To reduce excess works from workers.

Data Collection and Analysis

Operation Bulletin (For a V neck T-Shirt):

 

Buyer:
Hellenic
Style No:M black

Unit:

Style Description: L/ Regnce sleeve Round neck sweat T-shirt with sleeve Cuff joint .
Total SMV

9.92

Target  100 %

2540

Factory:The Delta Composite Knitting Ind. Ltd.
Machine/Operators SMV

MC

6.88

TGT(Prd 72%)

1829

No. of
Direct OP.

27

Prepared By:Production Engineering Dept.
Manual ( Helpers ) SMV

M

3.04

Bal. Loss(%)

13%

No. of
Helpers

15

Date: 10.01.2011
Working time(Mins)

600

Pcs/Manpower

43.55

Total Plan
Manpower

42

Revision No:1

 

 

    

 

 

 

 

 

Sl
No

Ref
code

Description

Manual/ Machine

Machine

SMV

Operator

TGT / Hrs

Remarks

Reqd

Alotd

1

159

V-point point attach by pm

MC

P/M

0.26

0.95

1

231

2

161

V-point point T/S by C/B(N)

MC

C/B(N)

0.22

0.81

1

273

3

103

Check & Trim

M

Manual

0.22

0.81

1

273

4

178

Zigzag end point tuck

MC

P/M

0.26

0.95

1

231

5

179

Zigzag end point stitch opening

M

Cutting

0.28

1.03

1

214

6

237

Sleeve set w/ front part

M

Manual

0.24

0.88

1

250

7

238

Sleeve joint w/ front part

MC

O/L

0.45

1.65

2

133

8

239

Sleeve T/S w/ front part

MC

C/B(N)

0.38

1.39

1

158

9

69

Check & Trim

M

Manual

0.18

0.66

2

333

10

60

Set front & Back

M

Manual

0.24

0.88

1

250

11

244

Sleeve joint w/ front part(one side)

MC

O/L

0.22

0.81

1

273

12

240

Sleeve T/S w/ front part(one side)

MC

C/B(N)

0.2

0.73

1

300

13

62

Neck piping by F/B

MC

F/B(N)

0.3

1.10

1

200

14

63

Piping cut

M

Scissor

0.2

0.73

1

300

15

243

Neck 1/4 Tuck

MC

P/M

0.2

0.73

1

300

16

241

Sleeve joint w/ front part(Other side)

MC

O/L

0.22

0.81

1

273

17

242

Sleeve T/S w/ front part(Other side)

MC

C/B(N)

0.2

0.73

1

300

18

69

Check & Trim

M

Manual

0.18

0.66

1

333

19

101

Neck 1/4 Tuck

MC

P/M

0.22

0.81

1

273

20

77

Label cut & make

MC

P/M

0.26

0.95

1

231

21

126

Side Seam joint w/care label

MC

O/L

0.85

3.12

3

71

22

91

Thread trimming

M

Manual

0.17

0.62

1

353

23

182

Label cut & fold by iron

M

Scissor

0.25

0.92

1

240

24

14

Label position mark

M

Manual

0.18

0.66

1

333

25

16

Label attach at back

MC

P/M

0.3

1.10

1

200

26

169

Cuff rib make & extra cut

MC

P/M

0.4

1.47

2

150

27

170

Cuff rib fold

M

Manual

0.26

0.95

1

231

28

171

Cuff Joint

MC

O/L

0.54

1.98

2

111

29

91

Thread trimming

M

Manual

0.17

0.62

1

353

30

174

Bottom Rib make & extra cut

MC

P/M

0.3

1.10

1

200

31

175

Bottom Rib serving

MC

O/L

0.5

1.83

2

120

32

177

Bottom Rib joint

MC

O/L

0.6

2.20

2

100

33

91

Thread trimming

M

Manual

0.17

0.62

1

353

34

102

Finishing thread cut &staker remove

M

Manual

0.3

1.10

1

200

 

Style

P/M

O/LC/B(N)C/B(S)F/B(F)

F/B(N)

B/A

B/H

Scolap

Other

Iron

Total

Total SMV9.92
TARGET PER HOUR298
TARGET PER HOUR209
Total operator26
Total Helper14
Total Man Power40
Basic Pitch Timeo.20
Cycle Time

 Objective:

  1. To maintain line balancing operation bulletin must need.
  2. To reduce bottleneck.
  3. To do capacity study more efficiently.
  4. To give Target per hour.
  5. To know how many workers needed.

 Analysis:

Produced Pcs during study93 Pcs/HrTotal productive time54 MinSignature
Previous best Achived90 Pcs/HrTotal Non productive time6 minWorkerNasima
Target improvement3 Pcs/HrNon Productive %11.10%Line Chief
Improvement %3.33%Total Observe Time1 hourPM
Avg: Capacity time35 SecTotal Study Time1 hourWSO
Capacity target110 Pcs/HrError
Remarks

 

Objective:

  • Production study is used to calculate the actual production of a worker per hours.
  • To calculate the actual production we have to see the total working minute in hour without lost time.
  • To know target of a worker.
  • To evaluate the finishing time of an item or product.
  • Production study helps for planning to maintain the layout and line balancing of machine and product.
  • For use as the basis for determining the unit cost of manufacture and the wage rate.
  • For use the basis for introducing a production control system.

List of machinery:

  1.  Plain machine or single needle lock stitch  Sewing machine.
  2.  Over lock sewing machine.
  3.  Flat lock machine.
  4.  Button attach machine.
  5.  Button hole machine.
  6. Bartack machine.
  7.  Snap button or eyelet or repet machine.
  8.  Kansai machine.
  9.  Smoke machine.
  10.  Feed of arm sewing machine.
  11. Backtap machine.
  12.  Two needle chain stitch machine.

Machine Layout:

BuyerStyleItemSMVLineUnitDay
End Line Quality Checking Table
31OPM/COperation NameSMVTGTCentre Table32OPM/COperation NameSMVTGT
M/CO/LBottom Rib serving0.5120M/CO/LBottom Rib joint0.6100
Seq#OPM/COperation NameSMVTGTSeq#OPM/COperation NameSMVTGT
2930
MManualThread trimming0.17353M/CP/MBottom Rib make & extra cut0.3200
Seq#OPM/COperation NameSMVTGTSeq#OPM/COperation NameSMVTGT
2728
MManualCuff rib fold0.26231M/CO/LCuff Joint0.54111
Seq#OPM/COperation NameSMVTGTSeq#OPM/COperation NameSMVTGT
2526
M/CP/MLabel attach at back0.3200M/CP/MCuff rib make & extra cut0.4150
Seq#OPM/COperation NameSMVTGTSeq#OPM/COperation NameSMVTGT
2324
MScissorLabel cut & fold b0.25240MManualLabel position0.18333
Seq#OPM/COperation NameSMVTGTSeq#OPM/COperation NameSMVTGT
21

 

 Objective:

  • Production study is used to calculate the actual production of a worker per hours.
  • To calculate the actual production we have to see the total working minute in hour without lost time.
  • To know target of a worker.
  • To evaluate the finishing time of an item or product.
  • Production study helps for planning to maintain the layout and line balancing of machine and product.
  • For use as the basis for determining the unit cost of manufacture and the wage rate.
  • For use the basis for introducing a production control system.

SMV Calculation:

Total basic time/garment (brought forward):      1.416

Add machine attention allowances                       7%

7% for (0.480 + 0.504) = 0.07 x 0.984 =0.069           0.069

Basic time + MAA (1.416 + 0.069)                       1.485

Add personal needs and relaxation allowances14%

14% of 1.485 = 0.14 x 1.485 = 0.208                   0.028

Standard minute Value (SMV) =Basic time + all allowances

=1.485 + 0.208 = 1.693 (SMV)

Analysis of SMV Calculation:

  • First we have to calculate G.Total Avg.BT (Basic Time) by adding all basic time of a worker for this operation.
  • G.Total Avg.BT is introduced by all OT (Observe Time) of a worker for this operation, and then OT is divided by the reading which is taken.
  • Total Allowances of a worker is maximum 19% (M/C Delay Allowance is 7% and Relaxation and Contingency Allowance is 12%)
  • Then all data put into the formula to calculate the SMV.
  • To understand the production capacity of the factory, and to draw up plans for the appropriate target output, suitable range of divided labor and optimum production (Scheduling, personnel planning or equipment planning)
  • To determine the time value for each work compound under the motion study.
  • To obtain an evaluation standard for receiving planning, using the time study as the basis of the cost estimate and control.
  • For use as the basis for determining the unit cost of manufacture and the wage rate.
  • For use the basis for introducing a production control system.

Conclusion:

Industrial engineering is an important and essential part of any apparel industry. We learn all the implementations of the processes which we have studied theoretically. It gives us an opportunity to compare the theoretical knowledge with practical facts and thus develop our knowledge and skills. This project also gives us an opportunity to enlarge our knowledge of textile administration, production planning, procurement system, production process, and machineries and teach us to adjust with the industrial life.