PRODUCTIVITY IMPROVEMENT THROUGH LINE BALANCING

By

DHEERAJ GARG 12314803612

New Holland Fiat (India) Pvt. Ltd.

Plot No. 03, Udyog Kendra, Greater Noida-201306

Distt. Gautam Budh Nagar, U.P. India.

MAHARAJA AGRASEN INSTITUTE OF TECHNOLOGY, SEC-22 ROHINI DELHI-110084

A REPORT

ON

PRODUCTIVITY IMPROVEMENT THROUGH

LINE BALANCING

BY

DHEERAJ GARG 12314803612

A PROJECT REPORT SUBMITTED IN PARTIAL

FULFILMENT OF THE

REQUIREMENTS OF THE COURSE

INTERNSHIP-1

AND

INTERNSHIP-2

AT

New Holland Fiat (India) Pvt. Ltd., Greater Noida

Guides: 1. Professional Expert- Mr. Ankush Harchand

2. Associate Faculty- Mr. BRIJESH SHRIVASTAV

DEPARTMENT OF MECHANICAL AND AUTOMATION ENGINEERING

MAHARAJA AGRASEN INSTITUTE OF TECHNOLOGY, SEC-22 ROHINI DELHI-84

CERTIFICATE

This is to certify that the project report titled PRODUCTIVITY IMPROVEMENT THROUGH LINE BALANCING submitted by DHEERAJ GARG in partial fulfilment of the requirements of course at New Holland Fiat (India) Pvt. Limited as part of the degree of Bachelor Of Technology in Mechanical AND AUTOMATION ENGINEERING , MAHARAJ AGRASEN INSTITUTE OF TECHNOLOGY is a record of bonafide work carried out under our supervision and has not been submitted anywhere else for any other purpose.

Mr. Ankush Harchand

ACKNOWLEDGEMENT

It is my esteem privilege, to express deep sense of gratitude and indebtedness to the management of NEW HOLLAND AGRICULTURE for giving me the opportunity to complete project work on PRODUCTIVITY IMPROVEMENT THROUGH LINE BALANCING.

I wish to express my gratitude to Mr. Ankush Harchand for his expert and inspiring guidance, constructive criticism and constant encouragement during the course of this practical industrial training.

Sincere thanks and obligations are due to Mr. BRIJESH SHRIVASTAV

I would be failing in my duties if I do not thank Mr. Sunil Kumar Yadav, Mr. Sandeep Kumar & all the Associates of NEW HOLLAND who have helped me in everyway to complete my project.

Thanks are also due to all staff members of NEW HOLLAND and others who took lot of interest in assisting me during the training period and in making the report a success.

DHEERAJ GARG

ABSTRACT

Poor layout design is determine as a major problem contribution in industries. These particular problems thus affect the productivity and the line efficiency as well. Throughout the study, the aim is to proposed new layout to the related company to increase their productivity. The major step is to identify a bottleneck workstation in current layout. After identify related problems, the current layout is redesign by computing the standard time and processing time in each workstations. In each workstation the processing time is different and the longest time consumption is workstation will be identified as a bottleneck workstation. This related line is studied by time study techniques. The standard time is established by using a Work Measurement Technique known as MOST (Maynard Operations Sequence Technique) and to analyse the MOST data Computer Aided tool MDAT (Most Data Acquisition Tool) is used. The goal of the Project is to seek the best layout in terms of line efficiency and productivity rate hence proposed to the company. This layout has better line efficiency and rate of productivity.

TABLE OF CONTENTS

Page

ACKNOWLEDGEMENTS

ABSTRACT

TABLE OF CONTENTS

COMPANY PROFILE

LIST OF TABLES

LIST OF FIGURES

LIST OF SYMBOLS

LIST OF ABBREVIATIONS

CHAPTER 1 INTRODUCTION

1.1 Introduction

1.2 Project Background

1.3 Project Motivation

1.4 Problem Statement

1.5 Project Objective

1.6 Project Scopes

CHAPTER 2 LITERATURE REVIEW

2.1 Introduction

2.1.1 Literature Structure

2.2 Manual Assembly Line

2.2.1 Advantages of Manual Assembly Line

2.3 Types of Assembly Line

2.3.1 Single Model Line

2.3.2 Mixed Model Line

2.3.3 Batch Model Line

2.3.4 Advantages and Disadvantages of Mixed Model Line

2.4 Workstation

2.4.1 Workstation Design

CHAPTER 3 METHODOLOGY

3.1 Introduction

3.1.1 Methodology Flowchart

3.2 Identifying Problem Area

3.2.1 Drive Line

i. Rear Axle ass. Lineii. Trumpet ass. Line

iii. Transmission ass. Lineiv. Hydraulic Lift ass. line

3.3 Literature Reviews

3.3.1 Standard Time

i. Work Measurementii. MOST

iii. MOST study

3.3.2. Line Balancing

i. Objective of line balancingii. Terms in line balancing technique

iii. Steps in solving line balancing

COMPANY PROFILE

HISTORY OF NEW HOLLAND WORLDWIDE

The history of New Holland dates back to October 1872 with the humble beginning

of the New Holland Machine Works in a one person Farm-Equipment Repair shop. No one

paid much attention when a 26-year-old Machinist named Abraham Zimmerman opened a

tiny repair shop at New Holland, Pennsylvania, U.S.A.

The first machine build by Zimmerman was a small portable feed mill. Designated to be the

no.1 mill it launched the New Holland Machine Works into the feed grinding business, from

which, it has never departed.

Abraham Zimmerman decided to expand his little company by incorporation and selling

stocks to his friends and customers.

In 1895, the New Holland Machine Works became the New Holland Machine Company, a

name that would carry the firm to prominence in farm Equipment Company. During the next

half century, New Holland introduced highly successful machines such as Balers, Rock

Crushers, Limestone pulverizers, Conveyors, Milling Machines, Engines, Coal, Furnaces and

an early rotary Lawn Mower.

In 1947, New Holland Machine Company came under the ownership of Sperry Corporation;

additional plants were acquired in Mountville, Belleville, Pennsylvania and Lancaster. The

New Holland Machine Company was now poised to become the industry leader in grassland

farming in next decade and brought 100 new products into the line, including Fertilizers

spreaders, Farm wagons, crop dryers and crop drying fans.

In 1970 an exciting boldness characterized the company’s performance in the form of

introduction of more than 150 new and improved products of world class technology and

also engineering breakthroughs.

In 1986, Ford Motor Company purchased Sperry New Holland and formed New

Holland. It was a beginning of new era with Pennsylvania becoming the world headquarters

of the new company and within a year Versatile Manufacturing Limited of Canada was

acquired, adding to the company a highly respected line of horsepower four-wheel-drive-

tractor.

New Holland Products now have a presence across 149 countries with 45 Manufacturing

Plants and the 23 rd plant in India.

NEW HOLLAND FIAT INDIA

Major Milestones

1996 New Holland India established. 1997 Ground Breaking Ceremony of the Plant at Greater Noida. 1998 Inauguration of Training center. 1998 New Holland India launched the 5630 (70 HP Tractor). 1999 Plant Inauguration and Launch of 50 HP tractor New Holland 3630. 2001 New Holland 3230 (42 HP Tractor) launched. 2002 New Holland 3030 (35 HP Tractor) launched. 2003 New Holland 3630 TX – 55 HP launched. 2004 New Holland 5630 TX- 4WD launched. 2005 Launched 3630 TX+, 3130, 3600 and 5500 & 7500 models in both 2wheel and

4wheel drive version. 2007 New Holland NX Series (35hp, 40Hp and 45 Hp category) launched. 2008 100,000th Tractor Rolled Out. 3037 NX model launched. 2009 New Holland 3030MU, 3600-2, 6500, 3032, 3510, 4010, 4510 models launched. 2011 New Holland 3730 Super, TD-90D launched. 2012 New Holland 3630Turbo Super, 5500Turbo Super, 6500 Turbo Super, 7500

Turbo Super models launched. 2013 New Holland Fiat India Celebrates 250,000th Tractor Milestone.

NEW HOLLAND TRACTORS INDIA PVT. LTD.

New Holland is a part of the $ 15 Billion CNH Global N.V., the world leader in Agricultural

& Construction equipment, with North American and European roots going back to the

invention of the modern tractor.

New Holland has expanded its Manufacturing and Distribution network around the

world to become biggest global player in its Industry.

It is a market leader in over 50 countries and is supported by a global Dealer network of

12,400 dealers.

The products are manufactured in 45 manufacturing locations spread over 16 countries.

People who depend on them day to day for their livelihood use new Holland’s products.

Around the world in every continent, over 4 million New Holland Machines are now at

work, perfectly adapted to every climate, season and land.

In 1996, New Holland withdrew from the joint venture and established a 100%

subsidiary company (New Holland Tractors (India) Pvt. Ltd.) to provide the latest

technology to the Indian farmers.

New Holland’s global experience has enabled us in bringing technological upgradation in

tractors & farm machinery and its application to Indian agriculture.

The Company has focussed its strength in agricultural mechanization to build a world class tractor company in India. It’s rationale for investment in India is driven, primarily by its long involvement and in–depth understanding of the India agricultural industry.

NHI MISSION

To continuously create superior value for our customers, shareholders, employees and

business partners, by together building and growing a sound business network in India,

and achieving industry leadership and world-class standards in both products and

processes.

To be innovative Global Leader in agricultural equipment, Construction equipment and Financial service industries by providing solutions that drive customer success.

ABOUT NHI: THE PLANT

PRODUCTION SYSTEM

NHI adopts the assembly line production system for manufacturing of all kind of

models. The assembly lines are flexible and can produce various kinds of models at constant

rate with almost zero inventories between the lines. The plant layout is one of the best in

Asia. The plant layout and colouring scheme was proposed by FIAT Engineering, Italy.

SECTIONS IN THE PLANT:

1. ENGINE ASSEMBLY

2. MACHINE SHOP(CNC MACHINING)

3. PTO ASSEMBLY LINE

4. DRIVE LINE

5. TRACTOR ASSEMBLY LINE BEFORE PAINTING

6. TRACTOR ASSEMBLY LINE AFTER PAINTING

7. TOOL ROOM

8. FRONT AXLE SUB ASSEMBLY LINE

9. STORE AREA

10. FINISHING LINE

11. TESTING

12. MAJOR REWORK

13. OK TO SHIP LINE

14. TYRE SUB ASSEMBLY LINE

15. CED PAINT SHOP

16. TYRE YARD

DEPARTMENTS AT NHI PLANT

1. Design and engineering

2. Finance and accounts

3. Human Resource

4. Information System

5. Manufacturing

1. Supply Chain

Logistics, PPC, Procurement

2. SQA( Supplier Quality Assurance),Utility

6. Purchase

7. Sales and Marketing

Manufacturing:

Tractor assembly

Pre Paint Assembly

Post Paint Assembly

Front Axle sub Assembly

Tyre sub Assembly

Painting

Body Tractor

Sheet Metal Parts

Drive Line Assembly

Rear Axle Assembly

Transmission Case Assembly

Hydraulic Lift Assembly

Trumpet Assembly

Engine Assembly (3 Cylinder & 4 Cylinder)

Assembly

Testing

Machining

Transmission Case

Axle Casing

Trumpets (4 types)

Front Axle support

Rear Cover

Hydraulic Lift Body

Final Drive Cover

Master Clutch Housing 42 HP

Front Support 42 HP

CHAPTER 1

INTRODUCTION

1.1 Introduction

Quality product and capable to cope with customers demands are important aspects that should be take an account especially for automation industry. Management systems are also contributes in order to planning, controlling and measuring parameters related to the performance of the sectors. Companies should realize that the performance is depending on how well the production line in term of output.

Process layout, product layout and fixed-position layout are 3 basics types of layout. This project is interested on product layout. Product layout is defined as flow-shop layout where number of machine and work processes are arranged so that the products will pass through several workstation. Due to high demand the resources was rearranged from process layout to product layout. This required a sequence steps to make product. Industries often called as assembly lines.

Assembly lines are general described as progressive assembly linked by some type of material handling. This can be found especially for industries that assembles product such as automobiles part, electronics part, food and etc. An example of product layout is cafeteria, where customer trays are moving through series of workstations. However bottlenecks are often occurred in assembly line. This will cause delay in term of time and decreasing in line efficiency.

The aims of the study are improving the productivity and compute efficiency of an assembly line in large scale industry. The objective are redesign the layout for purposing to improve line performance. Computer aided simulation are implemented in this project in order to analyze and investigate the problems occurring in assembly line.

The model will select and using time study techniques it will be analyzed. The line balancing method is use to solve the problem. Comparison of the current layout and new layout are done. Simulation is done by MOST software to accomplish this study.

1.2 Project Background

“Manual assembly lines technology has made a significant contribution to the development of American industry in twentieth century” [ Groover , 2001]. This phrase emphasizes the importance of assembly line especially in several sectors such as automobiles, consumer appliances and those sectors that produced large quantities product. This indicates the success factors are depending on the efficiency of assembly line. Along assembly lines various operations can be done either manually, automatically or integrated. For manual operations, the workers will perform jobs like brazing, assemblers, welding and so on. Normally for manual process the station will equipped with aided stationary depends on type of tasks. Automation operations are done for high volume quantities with additional features on the workstation. However, assembly line suffered one major problem, bottleneck. This phenomenon is defined as stage where causes the entire process to slow down or stop. This can be due to improper scheduling, improper line balancing and machine breakdown or equipment repairing.

Improper line balancing for example is defined on distribution of workloads and workers are not equal along the assembly line. The workers are not assigning equally in each workstation. Machine breakdown sometimes contribute to bottlenecks problem since the products are moving and suddenly had to stop and it start accumulate at certain workstation. Due to this problem, there will one station that has maximum time to perform a task. This station is called bottle neck station [Groover, 2001]. Analysis will be performing to identify the location of bottlenecks. Furthermore the product will start to accumulate hence slow down the process yet reduce the line efficiency.

The production rate is depending on how well the line is running. In order to fixed or overcoming bottle necks problems, manual calculation has a limitation. Fact that to analyze every stations are impossible due to time consumption. Simulation is often used to determine the root of bottlenecks. The results are valid for engineers to predict the causes and effectiveness of current layout. New layout is proposed to overcoming this problem. Simulation is tools for conducting experiments without damaging and interfering in the real systems.

1.3 Project Motivation

Bottle necking and excessive workers are common problems rose in assembly line. These are the major problems that encounter and yet need to be overcome as soon as possible. Assemblers are often encounters this problems and if this happen it will be decreased the line efficiency and the targeted run rate. In preventing these problems, engineers should come out with a solution in order to fix these problems. One way to do so is using line balancing method. This aim is to minimizing workloads and workers on the assembly line while meeting a required output.

Due to competitiveness, meeting a required demand and provide continuous product are become important matters. In order to achieve this objective, assembly line should be design to make sure the flow is smoothly. Workers on assembly line are specialized person in particular area. Most of them have been exposed to various tasks and skilled have been developed.

A new layout is proposed to make sure the assembly line achieved required run rate. The layout will include the number of workers, the workloads and the flow of the products. Normally any changes of the layout depend on type of product, environment and company policies. Layout will be design based on the regulation provided by company. Software application also involve in the design since any changes will affect the productivity. Simulation becomes necessary tool in designing layout based on its capability to evaluate and improving current layout.

Analysis on assembly is important in order to achieve targeted productivity. Assembly line should be design smoothly and simulation should be done to predict the line efficiency and productivity difference between new layout and current layout.

1.4 Problem Statements

1. Reducing line efficiency.

In flow line production the product moves to one workstation due to time restriction. Once it gets stuck due to accumulation in certain workstation, it exceeds the cycle time in that station. Faster station is limited by slowest station. Thus, decreases the rate of productivity.

2. Unbalance workloads

Due to starving, the workers need to wait the products to come.

1.5 Project Objectives.

Two objectives are expected in the end of the project:

1. To improve productivity and efficiency of existing layout and new layout

2. To meet unpredictable demand

1.6 Project Scopes

The project will be conducted at manufacturing based company New Holland Agriculture, Greater Noida.

1. Software application, MOST is used to simulate data.

2. Comparison between existing and new layout.

3. Proposing new layout.

4. Stopwatch is used to take the time.

CHAPTER 2

LITERATURE REVIEW

2.1 Introduction

This chapter is to explore and gathered all information’s in order to understand clearly about line balancing. The information’s is come from reference books, journals and Training books (Provided by the Professional Expert). The structure of this chapter is shown in Figure 2.1. These sections are mainly concern about related knowledge about Line Balancing. In the middle part of the Literature Reviews, detailed explanation regarding types of assembly line, workstation, material handling system, line balancing and simulation. This particular area is discussed to give better understanding on what is purpose of this project.

2.1.1 Literature Structure

Figure 2.1: Literature Structure

Manual Assembly Line

Types of Assembly Line

Workstation

2.2 Manual Assembly Line

A manual assembly line is a production line that consists of a sequence of workstations where assembly tasks are performed by human workers [ Groover , 2001].

Products are assembled as they move along the line, at each station, a portion of the total work is performed on each unit. The common practice is to "launch" base parts onto the beginning of the line at regular intervals. Each base part travels through successive stations and workers add components that progressively build the product. A mechanized material transport system is typically used 10 move the base part along the line as it is gradually transformed into the final product. However, in some manual lines, the product is simply moved manually from station-to-station. The production rate of an assembly line is determined by its slowest station. Stations capable of working faster are ultimately limited by the slowest station. Using manual assembly line due to several reasons:

i) High or medium demandingii) Similar products.iii) Total work to assemble can be dividediv) Cost Estimation (possible to automate the operations).

The movements of products along manual assembly line can be accomplish by two ways manually and mechanized system.

Note: Different method but all units facing same sequence of stations.

2.2.1 The Advantages of Manual Assembly Line

The advantages of manual assembly line are

i) Specialization of Labour

Known as “division of labour” this principle mentioned that when a large job is divided into small portion and assigned to one worker this develop an expertise on that particular area.

ii) Interchangeable Parts

Components with sufficiently close tolerances that any part of certain type can be selected for assembly with its matting components, without interchangeable parts, assembly will require filling and fitting.

iii) Work Principle

Products should travel in minimum distances between the stations.

iv) Line Pacing.

Workers should complete the task within a certain cycle time, paces the line to maintain a required rate. Pacing usually found by means of mechanized conveyor.

2.3 Types of Assembly Line

An assembly line can be classed into three categories based on numbers of models assembled on the line and according to the line pace [Groover, 2000] which are:

i) Single - model lineii) Mixed – model lineiii) Batch model line

2.3.1 Single Model Line

A single – model line can be described as a line that assembles a single model. This line produces many units of one product with no variation. The tasks performed at each station are same for all units. Products with high demand are intended to this line. [Groover, 2001]

2.3.2 Mixed – Model Line

Mixed – model line is producing more than one model. They are made simultaneously on the same line. Once one model is worked at one stations, the other product are made at the other station. Thus, every station is equipped to perform various tasks needed to produce any model that moves through it. Many consumers product are assembled on mixed – model line.

2.3.3 Batch Model Line

This line produces each model in batches. Usually workstations are set up to produce required quantity of the first model then the stations are reconstructed to produce other model. Products are often assembled in batches when medium demand. It’s more economical to use one assembly line to produce several products in batches than build a separate line for each model.

2.3.4 Advantages and disadvantages of a Mixed Model Line

Mixed–model line is pioneered by Toyota and is actually figured out to produce several models without any changeover. Proper sequencing of the product assures the demand go smoothly on upstream suppliers. There are several benefits using mixed – model line which are:

i) No lost production time switching between models.

ii) High inventories typical of batch production are avoided.

iii) Production rates of different models can be adjusted as product demand changes.

Even though mixed – model line offered several advantages thus it has its own disadvantages. The disadvantages that found out here are:

i) Assigning tasks to workstations to equally the workload is complex.

ii) Determining the sequence models.

iii) Getting the right parts to each workstation for model currently at the station

2.4 Workstation

On manually assembly line workstation is designed along the work flow path so does one or more workers can perform the task. The work elements represent small portion of work that must be accomplished to assemble product. Workstations designed should conclude productivity, operator comfort, operator variety and safety. The number of operator may be different and one operator might monitor several workstations. Certain workstations are equipped with hand tools or powered tools to perform the task assigned in that station. The design is depending on how the workers perform the task. There are several processes to designs the workstations which are:

i) Examining tasks, operators and tools.

ii) Allocating tasks between operators and machines.

iii) Selecting or designing tools and fixtures.

iv) Physical arrangements optimization.

Commonly for assembly large products such as cars, trucks and major appliances the workers need to stand so that they can move about the station to perform tasks. Operator comfort is important.

Comfortableness assures that operators perform better. Most of workstation rarely equipped operators as individuals. Assembling small parts required the workers to sit so that they feel much comfortable to reduce fatigue risks. This will help them to work on more conducive and more accurate while performing tasks. The workers start to assemble near upstream and product continuously moving through several workstations until task is completed.

These are typically operations done on manual assembly line which are:

i) Application of Adhesive

ii) Riveting

iii) Cotter Pin Application

iv) Application of Sealants

2.4.1 Workstation Design

In general, the number of workstations, n is equal to the numbers of workers, W and manning level, M

n=WM

A workstation has length dimensions, Lst, where I denotes station i. Total length of assembly line, L is summation of each workstations length

L=∑i=1

n

L st

If the length assembly line (m,ft) , L and Lst = length of station I (m,ft) are equal

L=nLst

If using conveyor we have to determine the feed rate, fp, and assume time cycle, tc is constant throughout the line

f p= 1t c

CHAPTER 3

METHODOLOGY

3.1 Introduction

3.1.1 Methodology Structure

3.2 Identifying problem area

3.2.1 DRIVE LINE

The driveline is that assembly of the tractor which transfers power to the wheel from the engine. So basically it is one of the most important assembly in tractor.

Driveline consists four sub-assemblies. These four sub-assemblies are as follows:-

i) Rear axle Assembly.

ii) Trumpet Assembly.

iii) Transmission Assembly.

iv) Hydraulic lift Assembly.

In driveline the main line is Rear Axle Assembly Line and rest three are the feeder lines to it. As the driveline gets completed at the end of Rear Axle Line, it is then tested on Test Rig.

i) REAR AXLE ASSEMBLY LINE :

On this line assembly of driveline starts with washing of axle casing and fitting of the

pinion and differential in the casing. It has 10 stations and testing rig for the testing of drive

line. On Station No.: 2, the crown wheel gear is fitted and its backlash is checked. On Station

No.: 3, brake support and brake disc are assembled. On Station No.: 4, the rear cover of axle

casing is assembled. On Station No.: 6,the trumpets are assembled. On Station No.: 7, the

hydraulic lift is assembled and On Station No.: 8, the master clutch housing is assembled. On

Station No.9 ,the converter valve and drop box is assembled, if it is required according to

variant. On Station No.: , shifting forks and rods of master clutch housing is fitted and locked

by inserting balls.

ii) TRUMPET ASSEMBLY LINE :

The trumpets are assembled to tractors to increase its traction force or to increase the

torque with the help of axle shaft and bull gear. This line consists of three stations. On

trumpet assembly line, the parts are first washed in washing machine. In final drive cover,

the dust seal, cup seal, roller bearing and ball bearing is pressed with the help of stake and

hammer. The wheel shaft, bull gear, spacer and final drive cover are fitted by hydraulic

press. The wheel shaft is locked by security washer and hexagonal nut. The final drive cover

is buckle up with trumpet after fitting axle shaft. The trumpets are distinguished on bases of

number of teeth on bull gear and axle shaft gear. Left hand trumpet has longer splines on

axle shaft than right hand trumpet. The trumpets are fitted on drive line at rear axle station

no.: 6.

iii) TRANSMISSION ASSEMBLY LINE :

On this line, the Master Clutch Housing (M.C.H.) is assembled with gears, driver and

driven shafts with reverse gear. This line has washing machines and four stations. The

master clutch housing is also known as gear box of the tractor as it has all speed and torque

variable gears. If the variant of the tractor is center shift then shifting lever are assembled

on transmission line and if the model is side shift then the shifting lever are assembled on

rear axle line. MCH feed by transmission line is assembled at station No.: 8 in rear axle line.

In MCH there is only one epicyclic assembled to reduce or to increase the speed or torque

and engagement or disengagement by high-low gear.

Fig 3.1 Driveline

iv) HYDRAULIC LIFT ASSEMBLY LINE :

In this line the hydraulic lifts are assembled. This line have washing machine and four

stations and also a test rig. In the hydraulic lift of New Holland Tractors has one unique

feature i.e. liftomatic switch. Then washing of hydraulic housing is done and then copper

bushes are pressed into holes of housing. Then the rock shaft and the arms are assembled.

The various other sub-assemblies are assembled into the housing for its proper working.

Then its liftomatic switch and distributor are assembled at its last station. The working of

distributor is very important as it will decide the distribution of hydraulic oil and if it will not

work or get jammed due to any chip or other particles. Lift will stop its working. On test rig

the setting or positioning of direct control (D.C.) lever, position control (P.C.) lever and

liftomatic switch is done. On the testing rig the hydraulic lift is fully filled with special testing

oil and then tested. Hydraulic lift is then assembled at station no.: 7 of rear axle line as it is

feeder line of rear axle line.

3.3 literature Reviews

3.3.1 Standard time

The standard time is the time required by an average skilled operator, working at a

normal pace, to perform a specified task using a prescribed method. It includes appropriate

allowances to allow the person to recover from fatigue and, where necessary, an additional

allowance to cover contingent elements which may occur but have not been observed.

The standard time is established by using a Work Measurement Technique known as MOST (Maynard Operations Sequence Technique). MOST concentrates on the movement of objects. All the MOST data is analyzed using MDAT. MDAT is the software used for the MOST study. MDAT has 4 modules for MOST data generation, analysis & Monitoring.

i) Work Measurement

Work measurement = Work + Measurement

Work = Force x Distance

Work is considered to be done when an object/part is moved to a distance by using required force to move object/part.

For example

1. Pick up hammer & stake and move 3 steps to fit split pin with stake.

Work is not considered to be done when either force is not applied or part is not moved to a distance from its position.

For example

1. Hold hammer & stake in hand.

Measurement: Establishing the standards for defined work.

Work Measurement is the application of various techniques designed to establish the time standards for an average associate to carry out a specified job at normal pace using a defined method at a defined level of performance.

Average associate is the one who is having the necessary physical attributes and who possesses the required intelligence and education and has acquired the necessary skill and knowledge to carry out the work in hand to satisfactory standards of safety, quantity and quality.

Why work measurement is Essential?

Work measurement is essential for an organization to provide information for below activities:

1. Production Planning & Scheduling 2. Define & measure Performance3. Manpower requirement & planning4. Manufacturing cost5. Plan of machine & equipments

By having Time standards to complete an activity/process, a manager can:

f = 10 lbs.d = 0 in.

1. Determine the total labor cost for a product2. Determine No. of workmen needed3. Determine No. of workstation needed4. Determine type of machines & Equipments required5. Predict production cost6. Know about Non value Added Activities and eliminate them so as to improve

production.

Techniques of Work Measurement:

Various techniques of Work measurement are:

1. Stop Watch Time Study2. Work Sampling 3. PMTS (Predetermined Motion Time Systems) Techniques - It includes MTM, MOST

etc.

Time Study:

Earlier associates were given certain tasks. These tasks were broken down into elements or short activities. Each element was studied to determine which one of them is productive and which is non productive. Now keeping only the productive elements, a stopwatch was used to determine the time for each. The time recorded was the actual time taken by average associate to perform a certain task under specific conditions. Now each associate is given a Performance Rating with respect to the qualified associate.

Advantages of Time study:

1. Fast to Apply2. Easy to learn

Disadvantages of Time study:

1. Subjective to an observer for performance rating2. Requires work to be performed by operator3. Requires continuous observations of repeated work cycle for accuracy.

Work Sampling:

1. Estimates percent of time a worker spends on various tasks

2. Requires random observations to record worker activity

3. Determines how employees allocate their time

4. Can be used to set staffing levels, reassign duties, estimate costs, and set delay allowances.

Motion study:

Gilbreth reasoned that to complete an activity, one of a set of fundamental motions are required.

The set consists of 18 elements, each describing a standardized activity. These activities he named as therblig (the word therblig is a reversal of the word Gilbreth, with 'th' treated as one letter.)

This method is often referred to as motion study.

Predetermined Motion Time System (PMTS):

By combining Time and Motion studies was born the Predetermined Motion Time System (PMTS).

PMTS is a work measurement technique that uses tables of standard times which are assigned to fundamental body motions that are required to complete an activity. The times for the fundamental motions are added to determine the normal time for performing the activity.

ii) MOST

MOST stands for Maynard Operations Sequence Technique. MOST is considered

revolutionary PMTS. It was developed by Kjell Zandin & HB Maynard & company in 1974.

MOST concentrates on the movement of objects.

Objects can be moved in any one of the two ways:

1. Picked up and moved freely through space.2. Moved while maintaining contact with another surface or along a controlled path

MOST can be applied in the following areas Administrative

Assembly

Fabrication

Machining

Maintenance

Material Handling

Other types of manual work

MOST can be applied in industry applications

Aerospace

Automotive

Distribution

Electronics

Manufacturing

MOST Work Measurement Systems:

On basis of type of application & ease to implement MOST is categorized into four main sub groups. These are

1. BasicMOST 2. MiniMOST 3. MaxiMOST4. AdminMOST

BasicMOST

It is typically used for activities that are ‘medium cycle’ (Cycle time varying from few sec. to approx. 10 min.) and also for repetitive and non repetitive activities.

It is the most commonly used version of MOST

MiniMOST

It is typically used for activities that are ‘short cycle’ (Cycle time of 20 sec or less) and are highly repetitive and feature very little variation.

It produces a very detailed and precise analysis.

MaxiMOST

It is typically used for setups , heavy assembly ,maintenance or utilities It is typically used in ‘longer cycle’ activities (cycle time of more than 2 min to several

hours) It also finds its application in activities that are non repetitive or vary widely from

cycle to cycle variations

AdminMOST

It is the version of BasicMOST that focuses on analyzing administrative and clerical activities.

It is the most commonly used for office related activities.

Procedure for selection of appropriate MOST system

Advantages of MOST:

Efficiently estimates the time to perform a task Accurate results Easy to understand & use Generates consistent results Encourages method improvement and continuous improvement Can be used in a wide variety of industries It ensures 100% performance level Activity timings can be obtained in advance

MOST analysis

Sequence Model

Phases

Parameters (A,B,G…)

Index values (1,3,6…)

Method Description

BasicMOST

BasicMOST is by far the most commonly used version of MOST. At the intermediate level, activities that are likely to be performed more than 150 but less than 1500 times per week should be analyzed with BasicMOST. An operation in this category may range from a few seconds to 10 minutes in length based on activities. The majority of operations in most industries fall into this category.

BasicMOST index ranges readily accommodate the cycle-to-cycle variations typical at this level.

The method descriptions that result from BasicMOST analyses are practical and sufficiently detailed for use as operator instructions.

The sequence models of BasicMOST represent the two basic activities necessary to measure manual work: General Move and Controlled Move.

Method Description:

Method description is written to document the action/s as per MOST terminology to make actions Clear, concise & easy to understand.

For Example:

Pick up a marker that is three steps away on the floor and lay the marker aside on the flip chart.

Method Description:

Move 3 steps, bend & arise, grasp marker from floor, Move 3 steps, put on flip chart.

Three activity sequences in MOST:

• The General Move Sequence (for a free movement through air)

• The Controlled Move Sequence (for a movement in which the object remains in contact with a surface or is attached to another object during the movement)

• The Tool Use Sequence (for the use of common hand tools)

Sequence Models:

The sequence model represents the complete activity of moving one or more objects from one location to another or the activity of using tools.

The sequence model takes the form of a fixed series of letters (called parameters) representing each of the various sub-activities of a General Move.

The parameters of the General Move Sequence Model identify the sub-activities.

A B G A B P A

Where:

A = Action Distance

B = Body Motion

G = Gain Control

P = Placement

Each letter in the sequence model represents a parameter that helps describe the action.

Basic MOST work measurement technique.

activity Sequence model Parameters

General move ABG ABP A A-Action Distance

B-Body Motion

G-Gain Control

P-Placement

Controlled Move ABG MXI A M-Move Controlled

P-Process Time

I-Alignment

Tool Use ABG ABP _ ABP A F – Fasten

L – Loosen

C – Cut

S – Surface Treat

M – Measure

R – Record

T - Think

These parameters are arranged in a sequence model organized in a logical sequence. The sequence model defines the events or actions that always take place in a prescribed order when an object is being moved from one location to another.

Sequence models represent these basic activities:

1. General Move

General Move is defined as moving objects manually from one location to another freely through air.General Move Sequence describes the manual movement of an object freely through space (unrestricted path).

General Move follows a fixed sequence of sub activities identified by the following steps:

1. Reach with one or two hands a distance to an object either directly or in conjunction with body motions or steps.

2. Gain manual control of the object.3. Move the object a distance to the point of placement, either directly or in

conjunction with body motions or steps. 4. Place the object in a temporary or final position.5. Return to the workplace.

ABG ABP A

Where the first three parameters (A B G) represent basic motions to get an object, the next three parameters (A B P) represent motions to put or move the object to a new location, and the final parameter (A) applies to any motions at the end of the sequence, such as return to original position.

2. Controlled Move

The Controlled Move Sequence describes the manual movement of a part over a controlled or restricted path. That is, movement of the object is restricted to atleast one direction by contact with or attachment to another object or the nature of work demands that the object be deliberately moved along a specific or controlled path.

The Control Move Sequence Model follows a fixed sequence of sub activities identified by the following steps:

1. Reach with one or two hands a distance to the object, either directly or in conjunction with body motions or steps.

2. Gain manual control of the object.3. Move the object over a controlled path (within reach or with steps)4. Allow time for a machine process to occur.5. Align the object following the Move Controlled or at the conclusion of the process

time.6. Return to the workplace.

These six sub activities form the basis for the activity sequence describing the manual displacement of an object over a controlled path.

ABG MXI A

3. Tool Use

The Tool Use Sequence describes the process of using a hand tool for activities such as fastening or loosening, cutting, cleaning, gauging, recording or inspecting.

In BasicMOST Tool Use Sequence Model have been created to describe these multiple moves in terms of the body member performing the action (i.e., finger, wrist or arm).

Special Tool Action parameters have been developed not only for fastening and loosening using common hand tools, but also for activities related to cutting, surface treating, measuring, recording and—even thinking!

Any activity involving a hand tool can be analyzed as a series of General and/or Controlled Moves but because of the ease of use, the consistency provided and the analysis time saved, such sets of multiple moves are usually analyzed with the Tool Use Sequence Model.

Different types of common tools used in industry are:

Hand or fingers (when used like a tool)

Wrenches

Ratchets

Box end Open end T-wrench Hexagon Adjustable Power

Pliers

Cutting Slip-joint Locking

Measuring Tools

Fixed scale Steel tape Caliper Micrometer

Cleaning Tools

Brush Wiping cloth Air nozzle

Gauges

Feeler Profile Thread Snap Plug Depth

Writing Tools

Pencil Pen Marker Stylus Scribe

Other Tools

Screwdriver Hammer Cutting Tools Scissors

Tool use Move follows a fixed sequence of sub activities identified by the following steps:

1. Get Tool: Reach with hand a distance to tool or object, either directly or in

conjunction with body motions or steps. Gain manual control of the tool or object.

2. Put Tool: Move the tool or object a distance to where it will be used, either directly or

in conjunction with body motions or steps. Place the tool or object in position for use.

3. Tool Action : Apply number or extent of Tool Actions.

4. Tool Aside : Retain the tool or object for further use Toss or lay the tool aside Return the tool to its original location Move it to a new location for disposition, either directly or in conjunction

with body motions or steps.

5. Return: Return to the workplace.

ABG ABP ( Tool Use) ABP A

Index Values:

Each of the parameters in above sequence models is assigned a number value based on the motion needed to perform an activity. This number is known as Index value. Index values are then used to generate the total time required to perform a task.

A standard data card is available index values of each parameter.

Time Calculation:

After method description & sequence is completed for an action, we need to convert Index values into standard units of time like seconds or minutes or hours.

This is done as per below steps:

1. Sum the index values.2. Multiply by a factor of 10 to get time value (in BasicMOST)

This time value arrived is Know as Time Measuring Unit, TMU.

TMU can be converted into Normal time (seconds, minutes or hours) as per below factors.

1 TMU = 0.00001 hour

1 TMU = 0.0006 minutes

1 TMU = 0.036 seconds

Alternatively

1 Hour = 100,000 TMU

1 Minute = 1667 TMU

1 Second = 27.8 TMU

In this we can convert TMU into seconds or minutes or hours.

iii)MOST Study

Approach

MOST study starts with the process observation. Observation can be in the form of direct observation of the process & may also be supported by video of the process.

Process observation is done for a stable process with the observer having basic knowledge of the process.

Stable process is the process where in no major variations are observed from one cycle to another.

Process Observati

onMethod Steps in

WM moduleMethod Steps in

WM module

Self validation of Method

StepsSelf

validation of Method

StepsUpdation of Method Steps in

WMUpdation of Method Steps in

WM

Validation of Method Steps with

process owner

Updation of Method Steps in

WMLink BOM parts in

WM module

MOST data

reports generatio

n

All the MOST data is analyzed using MDAT. MDAT is the software used for the MOST study.

MDAT - MOST Data Acquisition Tool

MDAT has 4 modules for MOST data generation, analysis & Monitoring.

1. WM –Work Measurement

This module is used for

Creating and Validating Sub Operations and Operations. Cycle Time and Content of Work calculations are done for all Operations

using Standard Sub Operations Library. BOM parts linking with operation/sub operations.

2. PDMS – Process Data Management System

This module is used for

Product and Part Routing Process Sheets, Videos, Drawings, CP, SOP, PFMEA Lean Work Content Analysis

3. LB – Line Balancing

This module is used for

Automatic Assembly Line Balancing Man-Machine Balancing

4. MOP – Measure Of Performance

This module is used for

Analysis Every Shift Production and Manpower related data Section wise, deptt. wise plant wise MOP data

Ease of operator allocation & Operator wise report generation.

3.3.2 Line Balancing

Line balancing is commonly technique to solve problems occurred in assembly line. Line balancing is a technique to minimize imbalance between workers and workloads in order to achieve required run rate. This can be done by equalizing the amount of work in each station and assign the smallest number of workers in the particular workstation. Here the job is divided into small portion called “job element”. The aim is to maintain production at an equal rate. Line balancing operates under two conditions:

i) Precedence Constraint.

Products can’t move to other station if it doesn’t fulfil required task at that station. It shouldn’t across other station because certain part needs to be done before others.

ii) Cycle time Restriction

Cycle time is maximum time for products spend in every workstation. Different workstation has different cycle time.

i) Objective of Line Balancing

Line balancing technique is used to:

a) To manage the workloads among assemblerb) To identify the location of bottleneck.c) To determine number of workstation.d) To reduce production cost.

ii) Terms in Line Balancing Technique

In assembly line balancing system, there is various term normally used. Each of them has their meaning and purposes. Below are several common terms found in assembly line balancing system :

a) Cycle Time

Maximum amount of time allowed at each station. This can be found by dividing required units to production time available per day.

b) Lead Time

Summation of production times along the assembly line.

c) Bottleneck

Delay in transmission that slow down the production rate. This can be overcome by balancing the line.

d) Precedence

It can be represented by nodes or graph. In assembly line the products have to obey this rule. The product can’t be move to the next station if it doesn’t complete at the previous station. Figure 2.8 shows the precedence graph. The products flow from one station to the other station.

Figure 2.3: Example of Precedence Diagram.

e) Idle time

W1

W4

W6 W7

W5

W2 W3

W8

A period when system is not in use but is available.

f) Productivity

Define as ratio of output over input. Productivity is depends on several factors such as workers skills, jobs method and machine used.

iii) Steps in Solving Line Balancing

Here are the steps in solving line balancing according to:

a) Drawing Precedence Diagram

Precedence diagram needs to be drawn to show a connection between a workstation. Certain process begins when previous process was done.

b) Determining Cycle Time

Cycle time is longest time allowed at each station. This can be expressed by this formula:

Cycle time= availabletimeDesired output

This means the products needs to leave the workstations before its reach its cycle time.

c) Assigning tasks to workstation

The tasks allocations should be taken after completing a time cycle. It’s good to allocate tasks to workstation in the order of longest task times

Number of workstation=∑ TaskTime

Desired Actual time

d) Calculating an Efficiency Line

This will carried out to find how effectiveness the line. The formula is given by:

Line efficiency=∑ oftask׿

Number of workstation∗Desiredcycle time∗100¿