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UNIVERSITI TEKNIKAL MALAYSIA MELAKA
Time Study Method Implementation In
Manufacturing Industry
Report submitted in accordance with the partial requirement of the Universiti
Teknikal Malaysia Melaka for the Bachelor of Manufacturing Engineering
(Manufacturing Process)
By
Nor Diana Hashim
Faculty of Manufacturing Engineering
May 2008
ABSTRACT
Time study is often referred to as work measurement and it involves the techniques
of establishing an allowed timed standard to perform a given task, with due
allowance for fatigue and for personal and unavoidable delays. Time study are used
for two main purposes in CTRM Aero Composites Sdn. Bhd., one for bidding new
projects and the other one is to monitor the production line. Each of the time study
techniques is applied under certain condition and the best technique for manual
production is the stopwatch time study because human performance is not consistent
from time to time. The stopwatch time study had been chosen for the case study
because 90 percents of the production in CTRM Aero Composites Sdn. Bhd. are
handled manually by man power. The aim of this case study is to find the suitable
rating factor and allowance for each process in order to conduct the stopwatch time
study for the panel produce by the CTRM Aero Composites Sdn. Bhd. and finally to
develope a time study database which will be used as a single source of reference by
the company.
Keywords: Time Study, Rating Factor, Allowances
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ABSTRAK
Kajian tentang masa atau juga selalu dirujuk sebagai pengukuran kerja adalah
mengenai lebihan masa yang dibenarkan dalam menjalankan sesuatu kerja
berdasarkan lebihan masa untuk keletihan, perkara peribadi dan perkara tertangguh.
Kajian tentang masa digunakan untuk dua tujuan utama di CTRM Aero Composites
Sdn. Bhd., yang pertama adalah untuk membida projek baru dan yang kedua untuk
mengawasi pengeluaran produk. Setiap teknik tersebut diaplikasikan dibawah
keadaan tertentu. Kajian tentang masa menggunakan jam randik telah dipilih untuk
menjalankan projek ini kerana 90 peratus produksi di CTRM Aero Composites Sdn.
Bhd. dilaksanakan secara manual dengan tenaga kerja manusia. Tujuan utama kajian
kes ini adalah untuk mendapatkan faktor kadar dan lebihan masa setiap proses bagi
menjalankan kajian tentang masa menggunakan jam randik untuk panel yang
dihasilkan oleh CTRM Aero Composites Sdn. Bhd. dan akhirnya membangunkan
suatu pangkalan data kajian tentang masa yang akan digunakan sebagai sumber yang
tunggal oleh syarikat tersebut.
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CHAPTER 1
INTRODUCTION
1.1 Background
As we approach the new millennium, with a widely expanded market and
manufacturing capability around the world, both the opportunities and the need for
technical competence are growing dramatically. According to Niebel (1993), ten years
ago the competition was centered in only a few industries - electronics and automotives
in particular. But today this competition is both industry wide and world wide. Each
department of these organizations is increasing the intensity of its cost reduction and
quality improvement effort in order to survive and expanding. Some companies have
even expanded their motion and time study method to nonmanufacturing activities with
the rise in the importance of indirect factory labor.
One of the oldest tools used by industrial engineers in work measurements is
time study and specifically stopwatch time study. Time study that originated by Taylor
and developed by Gilbreths was used mainly for determining time standards and motion
study. According to Rice (1977), over 89 percents of the companies that perform work
measurement used time study. The technologies are rapidly growing everyday but there
are still no tools that can replace time study method completely. They only invented
equipment that can improved the tools and made it users friendly. According to Niebel
(1993), computers produce standards from fundamental motion data up to 50 percents
faster than manual methods. The computers also provides a simple and convenient way
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to make time studies, monitor and measure machine and equipment performance, make
work sampling studies, and perform other data-gathering activities. Even though there
are many techniques and equipments to perform the time study, but basically the concept
is just the same.
In manufacturing industries, especially for industries that implement 90 percents
of manual production time study is very crucial. For example, manufacturing plant
management need time standards, even before production starts, to determine how many
people to hire, how many machines to buy, how fast to move conveyers, how to divide
work among employees, and how much the product will costs; after production starts, to
determine how much cost reduction will return, who works the hardest, and perhaps who
should earn more money; and after production finish, the data are used as reference for
bidding new projects and procurement. Time study can reduce and control costs,
improve working conditions and environment and motivate people.
Manufacturing management and engineers are prepared to design work stations,
develop efficient and effective work methods, establish time standards, balance
assembly lines, estimates labor costs, develop effective tooling, select proper equipment,
and lay out manufacturing facilities. However the most important thing is how to train
production workers in these skills and techniques so they can become motion and time
conscious. The manufacturing management and engineers only design and prepared the
skills but the production workers who are going to implement it in the operation. So the
objective of time study can only be achieved if the production workers are
knowledgeable about the time study concept.
1.2 Problem Statements
CTRM AC used Time Study for two main purposes, one for bidding new projects and
the other one is to monitor the manufacturing or production of current projects. The
current project needs to be monitor by using time study in order to control the cycle time
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and labor power of one project. Another point why time study suited with CTRM AC
because 90 percents of the production in this company is manual basis so there’s no
better tool to measure the work than time study because it include the rating factor and
allowances. In the mean time it also can be use as a tool for productivity improvement
and increase efficiency. Since time study is so important for the company, it had to be
done precisely with the element of allowance, rating factor and head count to produce a
standard time which can be used as reference to conclude the whole performance of
production.
1.3 Objectives of the Project
(i) To identify the suitable rating factors and allowances for the stopwatch
time study that suitable for manual production at CTRM AC.
(ii) To establishes cycle time from the current project on man hours and
machine hours by using time study method.
(iii) To develop a time study database for the company by using Microsoft
Excel 2003 that will be use as a single source reference of standard data
information.
1.4 Scopes of Project
To ensure the objectives will successfully achieve, there are several element that need to
be followed as well:
(i) Conduct a time study by including cycle time from observation with the
allowance and rating factors to produce standard time.
(ii) The study was undertaken by using stopwatch time study technique.
(iii) The research is going to be done at CTRM Aero Composites for project
Goodrich V2500 (Torque Ring Cone Fairing Panel).
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CHAPTER 2
LITERATURE REVIEW
2.1 Introduction
Time study is one of the oldest fundamental method ever used whose results in increased
productivity. Since the research are focus on the time study from all aspects, so the
history of the time study must be analysis and how it develop into the most useful tools
in manufacturing industry. Most of the source used for the studied comes from a reliable
and trustworthy source. The sources include articles, journals and books. There actually
more than one technique mention in this thesis but the research only focuses on one
method only. The method is stopwatch time study and it had been chosen because it
suitable with the industry in the case studies.
Any of the work-measurement techniques represent a better way to establish fair
production standard. All of these techniques are based on facts. All establish an allowed
time standards for performing a given task, with due allowance for fatigue and for
personal and unavoidable delays. Accurately establish time standards make it possible to
produce more within a given plant, increasing the efficiency of the equipment and the
operating personnel. Poorly established standards, although better than no standards at
all, lead to high costs, labor dissension and possibly even the failure of the enterprise.
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2.2 Chronology of Time Study
The Table 2.1 showed the major milestone of time study in the industry according to
year and the persona that contribute to the evaluation of the time study technique. The
descriptions of the persona are based on the contribution towards the time study fields.
Table 2.1: Chronology of Time Study
No. Year Persona Contribution1 1760 Jean Rodolphe
Perronet, French engineer
Extensive time studies on the manufacture of No. 6 common pins and arrived at a standard of 494 per hour (2.0243 hrs/1000).
2 1820 Charles W. Babbage, an English economist
Conducted time studies on manufacture of No. 11 common pins. It has determined that one pound (5,546 pins) should be produced in 7, 6892 hours (1.3864 hrs. /1000).
3 1856-1915 Frederick W. Taylor
The first person to use a stopwatch to study work content and as such is called the father of time study. He accomplishes the four Principles of Scientific Management. Responsible for the following innovations stopwatch time study, high-speed steel tools, tool grinders, slide riles and functional-type organization. He emphasized the analytical and organizational aspect of work.
4 1853-1931 Harrington Emerson
He was the expert that was needed to make Scientific Management, the Taylor system, a household name and his experience proved that the use of efficient methods would lead to tremendous savings. Accounts of his work were never extensively published and no comprehensive biography exists but his work is best remembered as an example of how the creative engineer can find the tools to improve any operation.
5 1861-1919 Henry Laurence Gantt
He invented the task and bonus system or earned-hour plan. He also developed a technique for scheduling work and performance control system. Rather than penalizing the less proficient worker, he
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advocated a livable wage with a sizable bonus for performance over 100 percents. He also designed the antisubmarine tactics known as convoy zigzagging that permitted escort ships to protect the slow freighters.
6 1868-1924 and 1878-1972
Frank and Lilian Gilbreth
Develop method study technique like cyclograph, chronocyclographs, movie cameras, motion picture camera and a special clock called a microchronometer. They also study fatigue, monotony, transfer of skills and assisted the handicapped in becoming more mobile. Their systematic study of motion reduced costs greatly and founded a new profession of method analysis. The Gilbreths also developed flow diagrams, process chart, and operation chart. Also the apprentice on the 17 elementary subdivisions of motion, later engineers coined a short word therblig.
7 1900-1984 Ralph M. Barnes
His achievements included writing the longest published text on work measurement, a through description of the Gilbreths micro motion study, time study and the procedure for work sampling.
2.3 Definition of Time Study
According to Meyers (2002), time standards can be defined as “the time required to
produce a product at a work station with the following three conditions: (1) a qualified,
well-trained operator, (2) working at a normal pace, and (3) doing a specific task.” The
three conditions are discussed below:
(i) A Qualified, Well-Trained Operator
Experience is usually what makes a qualified, well-trained operator and
time on the job is our best indication of experience. The time required to
become qualified varies with the job and the person. The greatest mistake
ever made by new time study personnel is time-studying someone too soon.
A good rule of thumb is to start with a qualified, fully trained person and to
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give that person two weeks on the job prior to the time study. On new jobs
or tasks, predetermined time study systems are used. These standards seem
hard to achieve at first because the time are set for qualified, well-trained
operators.
(ii) Normal Pace
Only one time standards can be used for each job, even though individual
differences of operators cause different results. A normal pace is
comfortable for most people.
(iii) A Specific Task
It is a detail description of what must be accomplished. The description
should include the prescribed work method, material specification, the tools
and equipment being used, the positions of incoming and outgoing material
and additional requirement like safety, quality, housekeeping and
maintenance tasks.
Time study is usually referred to as work measurement and it involves the technique of
establishing an allowed time standard to perform a given task, based on measurement of
the work content of the prescribed method and with due allowance for fatigue, personal
or unavoidable delays. Establishes time values are a step in systematic procedure of
developing new work centers and improving methods in existing work centers.
Generally time study is used to determine the time required by a qualified and well-
trained person working at a normal pace to do a specified task. The result of time study
is the time that a person suited to the job and fully trained in the specific method. The
job needs to be performed if he or she works at a normal or standard tempo. This time is
called the standard time for operation.
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Time study is composed of four parts:
(i) Developing the preferred method
(ii) Standardizing the operation
(iii) Determining the time standard
(iv)Training the operator
2.4 Objectives of Time Study
The principle objectives of time study are to increase productivity and product reliability
and lower unit cost, thus allowing more quality goods or services to be produced for
more people. The ability to produce more for less will result in more jobs for more
people for a greater number of hours per year. Only through the intelligent application of
the principles of time study can producers of goods and services increase while at the
same time, the purchasing potential of all consumers grows. Through these principles
unemployment and relief rolls can be minimized, thus reducing the spiraling cost of
economic support to nonproducers.
(i) Developing the preferred system and method-usually with the lowest cost
(ii) Standardizing this system and method
(iii) Determining the time required by a qualified and properly trained person
working at a normal pace to do a specific task or operation
(iv) Assisting in training the worker in the preferred method
Corollaries that apply to the principle objective are to (Niebel, 1993):
(i) Minimize the time required to perform tasks.
(ii) Continually improve the quality and the reliability of products and services.
(iii) Conserve resource and minimize cost by specifying the most appropriate
direct and indirect materials for the production of goods and services.
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(iv) Produces with a concern for the availability of power.
(v) Maximize the safety, health and well-being of all employees.
(vi) Produces with an increasing concern to protect our environment.
(vii) Follow a humane program of management that result in job interest and
satisfaction for each employee
5.1 The Important and Uses of Time Study
Although time study originally had its greatest application in connection with wage
incentives, it and the other methods measuring work are now used for many other
purposes including (Barnes, 1980):
(i) Determining schedules and planning work
(ii) Determining standard costs and as an aid in preparing budgets
(iii) Estimating the costs of a product before manufacturing it. Such information
is of value in preparing bids and determining selling price.
(iv) Determining machine effectiveness, the number of machines which one
person can operate, and as an aid in balancing assembly lines and work
done on a conveyor.
(v) Determining time standards to be used as a basis for labor cost control.
2.5 Time Study Techniques
The Table 2.2 showed the summary of time study techniques that had been discussed by
five different sources. Most of the technique had a same method but differ by name. The
detail descriptions on the techniques are discussed below.
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Table 2.2: Time Study Techniques by Source
No. Source Time Study Techniques1 Barnes, (1980). • Standard Data
• Work Sampling• Predetermined Time Standard System (PTS)• Stopwatch Time Study
2 Niebel, (1993). • Stopwatch Time Study• Computerized Data Collection• Standard Data• Fundamental Motion Data• Work Sampling and Historical Data
3 Lawrences, (2000). • Time Study• Standard Data Systems• Predetermined Time Systems (PTS)• Work Sampling• Physiological Work Measurement• Labor Reporting
4 Meyers and Stewart,(2002).
• Predetermined Time Standard System(PTSS)• Stopwatch Time Study• Work Sampling• Standard Data• Expert Opinion and Historical Data
5 Niebel and Freivalds, (2003).
• Time Study• Standard Data and Formulas• Predetermine Time Systems• Work Sampling• Indirect and Expense Labor Standards
4.1 Time Study in Non-Manufacturing Area
Together with the rise in the importance of indirect factory, there has come
tremendous increase in office work. Some companies have expanded their motion and
time study activities to include the office; others have establishes a separate department
to study office methods and procedures. The use of paper work simplification, office
work measurement, systems and procedures analysis, and procedure analysis, and office
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mechanization, and the installation of data-processing equipment are some of the
approaches being utilized to increase productivity and reduce costs in offices.
Banks, mail orders houses, hospitals, department stores, and supermarket are
obtaining worthwhile results from the applications of principles of motion and time
study to their activities. Great strides are being made in simplifying work on farms, as
well as in various branches of the government and military.
2.6 Description on Time study Method
Predetermined time systems, standard data, work sampling and stopwatch time study are
used for measuring work and these five methods of time study had been widely used for
various productions in the industry (Meyers and Stewart, 2002). Each of the different
method had their own criteria and concept that must be followed. Not all suitable for any
production, so here is the description of each method:
(i) Predetermined time standards system
This technique is used during the planning phase of a new project of a new
product development. At this stage, only sketchy information is available,
and the technologist must visualize what is needed in the way of tools,
equipment, and work methods. The technologist would design a work
station for each step of the new product manufacturing plan. Each work
station would be designed; a motion pattern would be developed. Each
motion would motion would be measured, a time value would be assigned,
and the total of these time values would be the time standard. This time
standard would be used to determine the equipment, space, and people
needs of the new product and its selling price. Frank and Lillian Gilbreth
developed the basic philosophy of predetermined time motion systems.
There are 17 wok elements that are known as therbligs. Each element was
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reduced to a time table, and when totaled, a time standards for that set of
motion was determined.
Methods time measurement (MTM), MODular Assignment at
Predetermined TimeS (MODAPTS) and Work Factors are popular
predetermined time systems inspired by the Gilbreths’ work. PTSS was
developed from MTM and other predetermined systems for the expressed
reason to teach a system within a few hours. PTSS is a simplified and good
system but additional training is desirable.
(ii) Stopwatch time study
Taylor (1856-1915) had started using the stopwatch around 1880 for
studying work. This technique is a part of many union contracts with
manufacturing companies. Several types of stopwatches could be used:
(a) Snapback: in one hundredths of a minute.
(b) Continuous: in one hundredths of a minute.
(c) Three watch: continuous watches.
(d) Digital: in one thousandths of a minute.
(e) TMU (time-measured unit): in one hundred thousandths of an hour
(f) Computer: in one thousandths of a minute.
All but the TMU watch read in decimal minutes. The TMU watch reads in
decimal hours. Digital watches and the computer are much more accurate
and have memory functions that improve accuracy.
Two different time study procedures are:
(a) Continuous time study.
(b) Long-cycle time study.
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(iii) Work sampling
Work sampling is the same scientific process used in Nielsen ratings,
Gallup Polls, attitude surveys, and federal unemployment statistics. We
observe people working and draw conclusions. Everyone who has ever
worked with someone else has done work sampling. Supervisors using
informal work sampling are forming attitudes about employees all the time.
Industrial technologists can walk through a plant of 250 people one time
and count people who are working and those who are not working and
calculate the performance of that plant within ±10 percent. Industrial
engineering often starts their consulting proposal with such statistics.
Consultants expect to find 60 percent performance in plants without
standards but that is an average.
(iv)Standard data
Standard data should be the objective of every motion and time study
department. Standard data is the fastest and cheapest technique of setting
time standards and standard data can be more accurate and consistent than
any other technique of time study. Starting with many previously set time
standards, the industrial technologist tries to figure out what causes the time
to vary from one job to another on a specific machine or class of machine.
There are several ways of communicating the time standards to future
generations of factory workers, supervisors and engineers:
(a) Graph
(b) Table
(c) Worksheet
(d) Formula
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(v) Expert opinion time standards and historical data
An expert opinion time standard is an estimation of the time required to do
a specific job. This estimation is made by a person with great experience
base and is usually a supervisor but sometimes it could be specialist or
planner. The expert would estimate every job and maintain a blacklog of
work. The blacklog of work would give the department time to plan the
job, thereby performing the job more effectively. Historical data is an
accounting approach to expert opinion time standard systems. A record is
kept of how much time was used on each job. When new job comes along,
it is compared to a previous job standard. The problem with historical time
standards is that they do not reflect the time the job should have taken.
Inefficiency is built into such a system, but a bad standard is better than no
standard at all.
2.7 Time Study Equipments
The equipment needed for time study work consists of a timing device and an
observation board. The devices most commonly used for measuring work area (Barnes,
1980):
(i) Decimal stop watches and electronics timers
(ii) The motion picture camera and video equipment
(iii) Electronic data collector and computer
(iv) Electrical and mechanical time recorders
(v) Observation board
(vi) Speed indicator/tachometer
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2.8 Making The Time Study
The exact procedure used in making the time studies may vary somewhat, depending
upon the type of operation being studied and the application that is to be made of the
data obtained. These eight steps, however, are usually required to perform time study in
industries (Barnes, 1980):
(i) Secure and record information about the operation and operator being
studied
(ii) Divide the operation into elements and record a complete description of the
method
(iii) Observe and record the time taken by the operator
(iv) Determine the number of cycle to be timed
(v) Rate the operator’s performance
(vi) Check to make certain that a sufficient number of cycle have been timed
(vii) Determine the allowances
(viii) Determine the time standard for the operation
2.9 Introduction to Stopwatch Time Study
The actual conduct of a time study is both an art and a science. To ensure success,
analyst must be able to inspire confidence in, exercise judgment and develop a
personable approach to everyone with whom they come in contact. In addition, their
backgrounds and training should prepare them to understand thoroughly and perform he
various functions related to the study. These elements include selecting the operator,
analyzing the job and breaking it down into its elements, recording the elapsed elemental
values, performance rating the operation, assigning appropriate allowance and working
up the study itself. There are two standard ways to record time study data (Barnes,
1980). The use of either method is a matter of analyst preference or company practice.
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The job must be divided into elements before choosing the method. These two methods
are:
(i) The continuous method
The data collection of this method involves starting the stopwatch when the
study begins and allowing it to run, uninterrupted, until the study is
complete. At the conclusion of each element, the current reading, or the
elapse time, is recorded on the data sheet. The continuous method is also
better adapted to measuring and recording very short elements.
(ii) The snapback method
In this method, after the watch is read at breakpoint of each element. The
watch time is returned to zero. As the next element takes place, the time
increments from zero. A drawback to using the snapback method is the
time that elapses while the hand sweep hand returns to zero. The snapback
method is also better adapted to measuring and recording long elements.
2.10 Rating, Leveling and Normalizing
Rating is the process of adjusting the time taken by an individual operator to what could
be expected from a normal operator. The method was developed by Mundel and Danner
(1994), eliminates the difficulty of establishing a normal speed criterion for every type
of work. Rating is a matter of judgment on the part of the time study analyst, and
unfortunately there is no way to establish a time standard for an operation without
having the judgment of the analyst. Rating an operator includes four factors:
(i) Skills
The effect of skill is minimized by timing only people who are skilled.
Operators must be fully trained in their work classification before being
time-studied. Habits of motion patterns must be routine enough that the
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operator doesn’t have to think about what comes next and where everything
is located. Very skilled operators make a job look easy, and the industrial
technologist must let this skill affect the rating.
(ii) Consistency
Consistency is the greatest indication of skill. The operator is consistent
when he or she runs the elements of the job in the same time, cycle after
cycle. Consistency is used to determine the number of cycles. A consistent
operator needs to run only a few parts before the cycle time is known with
accuracy. The skill of the operator should be evident to the time study
technician, and the technician’s rating of the operator should be high.
(iii) Working Conditions
Working conditions can affect the performance of an operator. In the early
twentieth century, this was much more of a problem than it is today. The
way we account for poor working conditions today is to increase the
allowance. Working conditions are not part of modern rating.
(iv) Effort
Effort is the most important factor in rating. Effort is the operator’s speed
and/or tempo and is measured based on the normal operator working at 100
percents.
Psychology has been good to the time study technicians. The normal tendency of people
being watched is to speed up. Being watched makes people nervous, and nervous energy
is converted by the body into a faster tempo. The time study technician then gets a
frequent chance to rate over 100 percent. When an operator works at 120 percent, the
technologist can give the operator 20 percent more time so that an average person can do
the job.
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9.1 Rating Methods
There are three rating methods that are usually being implemented in the
manufacturing industry (Barnes, 1980). The rating factors are as below:
(i) Speed rating
Speed rating is a performance evaluation method that only considers the
rate of accomplishment of the work per unit time. In this method, the
observer measures the effectiveness of the operator against the concept of a
qualified operator doing the same work, and then assigns a percentage to
indicate the ratio of the observed performance to normal or standard
performance.
In the speed rating method, analyst first appraise the performance to
determine whether it is above or below normal before putting the
performance to in the precise position on the rating scale that correctly
evaluates the numerical difference between the standard and the
performance demonstrated. Thus, 100 percent is usually considered normal.
A rating of 110 percent indicates that the operator was performing at a
speed 10 percent greater than normal, and a rating of 90 percent would
mean that the operator was performing at a speed 90 percent of normal.
(ii) Synthetic rating
The synthetic rating procedure determines a performance factor for
representative effort elements of the work cycle by comparing actual
elemental observed times to times developed through fundamental motion
data. Morrow, (1946) had established the synthetic rating in an effort to
develop rating method that would not rely on the judgment of a time study
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observer and would give consistent result. Thus, the performance factor
may be expressed algebraically as:
P = (F / O) (2.1)
where: P = performance or rating factor
F = fundamental motion time
O = observed man elemental time for the elements us in F
(iii) Objective rating
The method had been developed by Mundel and Danner (1994), eliminates
the difficulty of establishing a normal speed criterion for every type of
work. This procedure establishes a single work assignment to which the
pace of all other jobs is compared. After the judgment of pace, a secondary
factor assigned to the other job indicates its relative difficulty. Factors
influencing the difficulty adjustment are:
(a) Amount of body used
(b) Foot pedals
(c) Bimanualess
(d) Eye-hand coordination
(e) Handling or sensory requirements
(f) Weight handled or resistance encountered
Numerical values, resulting from experiments have been assigned for a
range of each factor. The sum of the numerical values for each of the six
factors comprises the secondary adjustment. The rating (R) can thus be
expressed as follows:
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R = P × D (2.2)
where: R = Rating
P = Pace rating factor
D = Job difficulty adjustment factor
9.2 Rating Applications
The first and most important characteristic of any rating system is accuracy. Since the
majority of rating techniques rely on the judgment of the time study observer, perfect
consistency in rating is impossible.
A rating system that is simple, concise, easily explained, and keyed to well-established
benchmarks is more successful than a complex rating system requiring involved
adjusting factors and computational techniques that confuse the average shop employee.
The value of rating is written in the RF column of the time study form. The value of
normal time can be calculated by using rating performance from the formula below
(Niebel and Freivalds, 2003):
NT = OT × R / 100 (2.3)
where: OT = mean observed time
NT = normal time
R = performance rating
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2.11 Allowance
Allowances are extra time added to the normal time to make the time standard practical
and attainable. No manager or supervisor expects employees to work every minute of
the hour. Types of allowance (Barnes, 1980):
(i) Personal
Personal allowances is that time an employee is allowed for personal things
such as talking to friends about nonwork subjects, going to the toilet,
getting a drink, going to pray or any other operator-controlled reason for
not working. An appropriate amount of time has been defined as about 5
percent of the work day, or 24 minutes per day.
(ii) Fatigue
Fatigue allowance is the time an employee is allowed for recuperation from
fatigue. Fatigue allowance time is given to employees in the form of work
breaks, more commonly known as coffee breaks. Breaks occur at varying
intervals and are of varying duration, but all breaks are designed to allow
employees to recuperate from on-the-job fatigue. Most employees today
have very little physical drudgery involved with their jobs, but mental
fatigue is just tiring. If an employee uses less than ten pounds of effort
during the operation of his job, then five percent fatigue allowance is
normal. A five percent increase in fatigue allowance is given for every ten-
pound increase in exertion required of the employee.
The breaks are calculated into the fatigue allowance because the reporting
practice is to not report the time spent on breaks separately. Because lunch
time is punched out and not reported, it does not enter into the allowance
calculation. Allowance is for times when the employees is expected to
perform but can’t.
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(iii) Delay
Delay allowances are called unavoidable because they are out of the
operator’s control. Something happens to prevent the operator from
working. The reason must be known and the cost accounted for to develop
the cost justification. The operator’s performance must not be penalized for
problems out of his or her control. Three methods are available to account
for and to control unavoidable delays:
(a) Add delay allowances to the standard
(b) Time-study them and add them to the time standard
(c) Charge the time to an indirect charge
For example, if the operator agrees that 15 minutes per day is a good figure,
the technologist will calculate a delay allowance as follows:
(15 min clean-up) / (480 min/shift) = 3%
A three percent allowance will be added to the personal allowance of five
percent plus a fatigue allowance of five percent to produce a 13 percent
total allowance.
An unavoidable delay is a foreign element that cannot be anticipated will
require the operator to charge his or her time to indirect account.
Supervisors will be required to approve all indirect charges and the time
should be more than six minutes to be statistically significant. Anything
that cannot be live with is not supposed to be in the time standard because
it is difficult to get it out once it included.
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2.11.1Allowances Application
The fundamental purpose of all allowances is to add enough time to normal production
to enable the average worker to meet the standard when performing at standard
performance. There are two ways of applying allowances (Niebel and Freivalds, 2003).
The most common is to add a percentage of the productive time only. It is also
customary to express the allowance as a multiplier, so that the normal time (NT) can be
readily adjusted to the standard time (ST).
ST = NT / (1- allowance) (2.4)
where : ST = standard time
NT = normal time
2.12 Summary of the Category Research
The Table 2.3 showed the summary of the category research of time study that related to
manufacturing industry. The summary is an analysis of the journals that related to the
time study and it had been divided into each sub-topic and category. The description of
each category is provided for better understanding.
Table 2.3: Summary of the Category Research of Time Study related to
Manufacturing Industry.
SUB-TOPIC CATEGORY AUTHOR/S DESCRIPTION
Definition of assembly cycle
time.
Choi and Ip, 1999; Hushizaki, 1990.
Assembly cycle time is the period of active time from starting to finishing an assembly operation and the operator
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2.10.1Introduction of
Time Study
(robot/human) is expected to be able to perform the task within the specified cycle time.
Definition of cycle time.
Hult and Nichols, 1999.
Cycle time is defined as the time takes from initiation to complete of the purchasing process which is often considered one of the most important performance indicators.
Wetherbe, 1995.
Cycle time is defined as the duration of the supply chain process from initiation to completion.
Narasimhan and Jayaram, 1998; Wetherbe, 1995.
Cycle time is the duration of the period between the internal customer’s recognition of a need to the provision of a good and service to that customer.
Escorpizo and Moore, 2007.
The time available to do one transfer (pick then place) will be referred to as cycle time.
Patel et al., 1994.
The cycle time of a product consists of the actual time to process for each operation, the waiting time before each operation and the transfer time between operations
Definition of manufacturing
cycle time.
Ballard et al., 2003.
Manufacturing cycle time is the time it takes for a product to be transformed from raw material to finished product.
2.10.2Main elements in
Time Study.
Work measurementWilding and Newton, 1996.
Time-based companies measure the cycle times and lead times of all their key activities.
The elementGriffin, 1997. Time can be considered
as the equivalent of
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