its work study and ergonomics

1. Full Name ID No
Gabbisa Gamise PGE/56687/14
Tasfaye Buli PGE/56696/14
Deda Abera PGE/56685/14
AMBO UNIVERSITY
HACHALU HUNDESSA CAMPUS
SCHOOL OF MECHANICAL AND INDUSTRIAL ENGINEERING
INDUSTRIAL ENGINEERING DEPARTMENT
Degree of Master of Science (M.Sc.) In Industrial Engineering and Management
Work Study & Ergonomics
Group Project
Summited to: .Tariku Tamiru, PhD
Submission Date: 11-02-2023
Ambo,Ethiopia

2. Introduction
 Work study is a generic term for the techniques of method study and work
measurement
 Work study succeeds because it is systematic both in the investigation of the
problem being considered and in the development of its solution.
 The project is about to study the existing method of different work stations
and suggesting improved method for the same so as to reduce the cycle time
and to improve productivity
 The importance of this project work is directly related to the reduction of the
stoppage time and increasing the productivity.
 The proposed work is done in mugher cement industry which engaged in
production of cement.

3. Problem Statement
 To study the existing method involved in welding and maintenance of cement
mill flanges and suggesting new improved methods using work study
techniques to reduce the stoppage time and improve productivity through
increasing working time of the mill without stoppage

4. Objectives of Study
 To suggest a new improved method to reduce the cycle time of the same.
 To minimize the stoppage time of the mill and also to minimize excess man
power.
 To propose a new method of performing the job and comparing it with the
existing method
 To study the present work process and identify bottle neck areas.

5. LITERATURE REVIEW
 Work study is a generic term for techniques, particularly method study and
work measurement
 Work study investigates the work done in an organization and aims at finding
the best and the most efficient way of utilizing the available resources to
achieve best possible quality work in minimum possible time and causes least
possible fatigue to the worker
 Method study is the systematic recording and critical examination of ways of
doing things in order to make improvements
 Work measurement is the application of techniques designed to establish the
time for a qualified worker to carry out a task at a defined rate of working

6. Method Study
 Method study is a systematic method of analyzing the manufacturing
procedure of doing a job
 it is the process of analyzing the methods and finding the best possible
method which involves minimum time, not make fatigue to the workers and
increase productivity
 Method study is generally done by eliminating all unnecessary motions

7. Method Study procedure
 Select the work which deserves to work-study and define the objective we
need to achieve
 Record all the relevant data which are essential for the method in chart form
to obtain a clear picture of the respective methods
 Process and multiple activity charts
 Making Diagrams
 Motion and Memo motion studies

8. Flow Process Chart
 A flowchart is a picture of the separate steps of a process in sequential order
 It is a generic tool that can be adapted for a wide variety of purposes, and
can be used to describe various processes, such as a manufacturing process,
an administrative or service process, or a project plan. It's a common process
analysis tool and one of the seven basic quality tools.
 Elements that may be included in a flowchart

9. Flow Process chart symbols
 Operation – Any operation for making altering or changing the job is said to
be an operation
 Inspection – Checking the quality and quantity
 Transport – Movement or travel of the job
 Delay or temporary storage – Breakdown, interface or time required for
some adjustments
 Storage This symbolizes an inventory hold, warehouse or work in progress
inventory bin/warehouse
b) Inspection – Checking the quality and quantity

10. When to Use a Flowchart
 To develop understanding of how a process is done
 To study a process for improvement
 To communicate to others how a process is done
 When better communication is needed between people involved with the
same process
 To document a process
 When planning a project

11. Flow Chart Basic Procedure
 . Define the process to be diagrammed
 . Discuss and decide on the boundaries of your process
 . Brainstorm the activities that take place
 . Arrange the activities in proper sequence
 When all activities are included and everyone agrees that the sequence is
correct, draw arrows to show the flow of the process.
 . Review the flowchart with others involved in the process to see if they agree
that the process is drawn accurately

12. Data Collection by Manual Work Study
Method
 Loosing each bolt that connect flange and shell
 Dismantle flange and shell
 Loading the 1st flange and transport it to work shop
 Adjusting
 Measuring
 cutting the 1st flange by oxyacetylene
 Cutting v groove on front side, to create bevel joint
 Grinding
 Rotate the flange
 Cutting v groove on back side, to create bevel joint
 Grinding
 Inspection and check for crack penetration
 Pre-clean part and make shine
 Apply dye penetrant
 Remove penetrant after it dry
 Apply developer
 Evaluate indications(inspection)
 Post-clean part
 Loading the 2nd flange and transport it to work shop
 Adjusting
 Measuring
 cutting the 2nd flange by oxyacetylene
 Cutting v groove on front side, to create bevel joint
 Grinding
 Design v on back side, to create bevel joint

13. Count..
 Grinding
 Inspection and check for crack penetration
 Pre-clean part and make shine
 Apply dye penetrant
 Remove penetrant after it dry
 Apply developer
 Evaluate indications(inspection)
 Post-clean part
 Adjusting two flanges to weld each other
 Inspection
 Heating front side of bevel joint
 Welding front side of bevel joint
 Inspection
 Rotate flanges to back sides
 Adjust it on the bench
 Remove porosity from back side of v groove
 Grind depth of v groove
 Heating backside of bevel joint
 Welding back side of bevel joint
 Inspection
 Rotate flanges to front sides
 Adjust it on the bench
 Apply heat treatment
 Inspection
 Transport it to the cement mill
 Assemble with the cement mill shell
 Tighten all bolts to the required torque

14. Some list of activity in picture
Measuring cutting

15. Count..
Grinding Adjusting

16. Operational Process Chart
 An operational process chart for cement mill flange welding and maintaining
in mugher cement is recommended as bellow

17. The 5W1H Method Has Many Applications
 It is perfectly suited, by virtue of its simplicity and versatility, to a variety of
structures, configurations and problems, and so it can be used at all levels of the
situation.
 The Followings Are the Application Area of the 5W1H
 At the industry level to design ore improve production through work study and
ergonomics
 At the strategy level to design or improve a market penetration strategy, for instance;
 At the management level to improve organization and processes during brainstorming
sessions;
 At the quality level as a problem-resolution support tool;
 At the innovation level to boost the emergence of solutions and ideas in the cause of
progress;
 At the project management level generally.

18. The Advantages of the 5W1H Method
 The strength of the 5W1H method lies in four key attributes:
 Simple: no need for training or people accredited in the method to
successfully ask these questions.
 Systematic: the key to success is to always ask all the questions, each and
every time.
 Versatile: it can be used equally well to design a new process as to
implement a corrective measure.
 Comprehensive: the method can be used to obtain a 360° view of the
problem and detect the route to resolution

19. no Statement 5w1h
what why when where who
1) Loosing each bolt that connect flange and shell Arranging necessary tools at a place/
site / torque wrench
To facilitate the jobs easily Before starting the jobs At work site Maintenance supervisor
1) Dismantle flange and shell Arranging necessary tools at a place To facilitate the jobs easily Before starting the jobs At work site Maintenance supervisor
1) cutting the 1st flange by automatic cutting machine Using automatic cutting machine To shorten working time Before starting the jobs At work shop Maintenance supervisor and welder
technician
1) cutting the 2nd flange by automatic cutting machine Using automatic cutting machine To shorten working time Before starting the jobs At work shop Maintenance supervisor and welder
technician
1) Adjusting two flanges to weld each other Preparing bench To handle and transport easily During dismantling parallel at the same
time
At work shop Maintenance technician
1) Welding front side of bevel joint Using summerged arc welding To shorten working time At work shop after proper adjustment At work shop welder technician
1) Welding back side of bevel joint Using summerged arc welding To shorten working time At work shop after proper adjustment At work shop welder technician
1) Tighten all bolts by using pneumatic torque Using pneumatic torque wrench To handle and carry out the job easily At site after transportation and proper
assembly
At site Maintenance technician

20. Work measurement
 Is the application of techniques designed to establish the time for an average
worker to carry out a specified manufacturing task at a defined level of
performance. It is concerned with the length of time it takes to complete a
work task assigned to a specific job.

21. Count..
 Attempts to measure work and to establish work standards
 It gives feeling to the workers that standards may result in more effective
control and they may be required to do hard work for lesser wages.
 Management feels that the use of standards may lead workers to work hard
which may result in higher wage bills.
 Application of techniques designed to establish the time for qualified
operator/worker to carry out a specified job at a defined level of
performance is called the work measurement.

22. A work has to be measured for the
following reasons:
 To discover and eliminate lost or ineffective time.
 the best method must be used
 materials must not be wasted;
 To establish standard times for performance measurement.
 To measure performance against realistic expectations.
 To set operating goals and objectives
 Developing the desired system and method usually the one with lowest cost.
 Standardizing the system and method.
 Determining the time required by a qualified and properly trained worker working at a
normal place to do a specific operation.
 the quality of the work must be satisfactory to the employer
 the machinery and equipment must be used properly
 safety standards must be maintained

23. Uses and objectives of Work Measurement:
 Target time for each job can be scientifically estimated, with this estimate realistic
schedules and manpower requirements can be prepared.
 Sound comparison of alternative methods is possible by comparing their basic times.
 Useful wage incentive schemes can be formulated on the basis of target times.
 In can lead to proper balancing of the work distribution.
 It can help to analyses the activities for performing a job with the view to eliminate or
reduce unnecessary or repetitive operations so that human effort can be minimized.
 To standardize the efficient method of performing operations.
 To standardize conditions for efficient performance.
 To determine man and machines ratio for effective and efficient utilization of both.
 To provide information’s and basis for production planning and scheduling activities.

24. Count…
 According to the manual work study the present method takes 637hours to
dismantle and welding the cement mill flange and the proposed method takes
479 hours to dismantle and welding the cement mill flange. Hence Savings is
158hours
 Standard time
 • % of improvement
 = ((Present method - Proposed method)/Present method)*100 •
 = ((637-479)/637)*100 •
 = 24.8%

25. Productivity Improvement
 It will improve the current process by reducing the unnecessary movements of
worker and by reducing workers fatigue.
 After implementing the suggested improvement areas the industry is able to
increase its productivity.

26. From process improvement we conclude that for mill
production capacity of 70 to/hr.
We calculate that
 Hence Savings is 158 hours
 Mill production capacity of 70 to/hr.
Total production improvement
= production capacity * Savings hours
= 70 to/hr. * 158 hours
=11,060 ton of cement
= 11,060 ton *10 kuntal
= 110,600 kuntal of cement
=110,600 *382 birr
= 42,249,200 birr

27. Count….
 Time studies are best suited for activities that involve a set of predictable
and repetitive actions.
 They are ideal in factory settings, where the production process can be
broken down into a series of sequential tasks and operator movements.

28. Count…
 By considering overall allowance of 15% standard time can be calculated
 Standard time = normal time + allowance
 Contingency allowance should not be more than 5%, and should only be given
where the contingencies cannot be eliminated and are justified.
 Typical values of relaxation allowance are 12-20%.
 Standard time is the total time in which a job should be completed at
standard performance

29. Element Description
Observation sheet
Cycle time Summary
1 2 3 4 5
𝑇 Tmean
PR NT ST
Loosing each bolt that connect flange and shell
48 51 49 48 52 240 48 80 38.4 44.16
Dismantle flange and shell 13 13 12 11 11 60 12 90
10.8 12.42
Loading the 1st flange transport it to work shop
10 7 7 9 7 40 8 80 6.4 7.36
Adjusting 10 7 7 9 7 40 8 110
8.8 10.12
Measuring 2.5 2.5 2 1.5 1.5 10 2 120
2.4 2.76
cutting the 1st flange by oxyacetylene 48 37 39 42 38 200 40 115
46 52.9
Cutting v groove on front side, to create bevel joint
16 17 16 15 16 80 16 120 19.2 22.08
Grinding 11 9 10 11 9 50 10 80
8 9.2
Rotate the flange 2.5 2.5 2 1.5 1.5 10 2 90
1.8 2.07
Cutting v groove on back side, to create bevel joint
24 25 25 24 22 120 24 120 28.8 33.12
Grinding 13 13 12 11 11 60 12 80
9.6 11.04
Inspection and check for crack penetration 7 6 5 6 6
30 6
90
5.4 6.21
Pre-clean part and make shine 4 6 5 6 4 25 5 110
5.5 6.325
Apply dye penetrant 2.5 2.5 2 1.5 1.5 10 2 120
2.4 2.76
Remove penetrant after it dry 5 5 3 4 3 20 4 110
4.4 5.06
Apply developer 1.5 1.5 2 2.5 2.5 10 2 120
2.4 2.76
Evaluate indications(inspection) 4 3 3 3 2 15 3 120
3.6 4.14
Post-clean part 2.5 2.5 2 1.5 1.5 10 2 120
2.4 2.76
Loading the 2nd flange and transport it to work shop
10 7 7 9 7 40 8 90 7.2 8.28
Adjusting 9 8 8 9 7 40 8 110
8.8 10.12
Measuring 1.5 2.5 2 2.5 1.5 10 2 120
2.4 2.76
cutting the 2nd flange by oxyacetylene 48 37 39 42 38
200 40
115
46 52.9
Cutting v groove on front side, to create bevel joint 16 17 16 15 16 80 16 120 19.2 22.08
Grinding 11 10 9 10 10 50 10 80
8 9.2
Design v on back side, to create bevel joint 24 25 25 24 22
120 24
120
28.8 33.12
Grinding 13 13 12 11 11 60 12 80
9.6 11.04
Inspection and check for crack penetration 7 6 5 6 6
30 6
90
5.4 6.21
Pre-clean part and make shine 4 6 5 6 4 25 5 110
5.5 6.325
Apply dye penetrant 2.5 1.5 2 1.5 2.5 10 2 120
2.4 2.76
Remove penetrant after it dry 5 3 4 5 3 20 4 110
4.4 5.06
Apply developer 2.5 2.5 2 1.5 1.5 10 2 120
2.4 2.76
Evaluate indications(inspection) 4 3 3 3 2 15 3 120
3.6 4.14
Post-clean part 2 3 2 1.5 1.5 10 2 120
2.4 2.76
Adjusting two flanges to weld each other 13 13 12 11 11
60 12
110
13.2 15.18
Inspection 5 4 3 2 2 15 3 90
2.7 3.105

30. Heating front side of bevel joint 5 4 4 4 3 20 4 80
3.2 3.68
Welding front side of bevel joint 52 51 49 50 48 250 50 80
40 46
Inspection 2.5 2 2 3 1.5 10 2 90
1.8 2.07
Rotate flanges to back sides 2.5 1.5 2 1.5 2
10 2
90
1.8 2.07
Adjust it on the bench 5 3 4 5 3 20 4 110
4.4 5.06
Remove porosity from back side of v groove 7 7 6 5 5
30 6
80
4.8 5.52
Grind depth of v groove 24 25 21 24 23 120 24 115
27.6 31.74
Heating backside of bevel joint 5 3 4 5 3 20 4 90
3.6 4.14
Welding back side of bevel joint 72 71 70 69 68 350 70 80
56 64.4
Inspection 3 2 2 1.5 1.5 10 2 90
1.8 2.07
Rotate flanges to front sides 10 7 7 9 7 40 8 90
7.2 8.28
Adjust it on the bench 5 3 4 5 3 20 4 110
4.4 5.06
Apply heat treatment 24 25 25 24 22 120 24 120
28.8 33.12
Inspection 2.5 2.5 2 1.5 1.5
10 2
90
1.8 2.07
Transport it to the cement mill 2.5 2 2.5 1.5 1.5 10 2 110
2.2 2.53
Assemble with the cement mill shell 48 51 49 48 52 240 48 90
43.2 49.68
Tighten all bolts 52 49 51 49 48 240 48 80
38.4 44.16
Total ` 649.3 746.695

31. Control Chart
 A control chart is a very powerful tool that determines a change in progress
over a period of time. The data is presented in a manner of time order. A
control chart is a medium that helps one to understand the behavior of
different processes.

32. Count….
 A control chart is very helpful because it determines if the process in control
or is it out of control, with the help of the three basic lines which composes
the:
– center line which represents the data’s median or average
– lower line that indicates lower limit
– upper line that upper limit
 A control chart is very helpful in verifying how effective the change in the
process is.
It helps to determine if the capability analysis is still is valid to be performed.
 Control charts provides convenient comparison in the shifts in the changes of
a process variation and a process mean.
 Control charts are also very essential because they assess performance of
process over a period of time.

33. Count…
0
10
20
30
40
50
60
70
80
Loosing
each
bolt
that…
Dismantle
flange
and
shell
Loading
the
1st
flange…
Adjusting
Measuring
cutting
the
1st
flange
by…
Cutting
v
groove
on
front…
Grinding
Rotate
the
flange
Cutting
v
groove
on
back…
Grinding
Inspection
and
check
for…
Pre-clean
part
and
make
shine
Apply
dye
penetrant
Remove
penetrant
after
it
dry
Apply
developer
Evaluate…
Post-clean
part
Loading
the
2nd
flange
and…
Adjusting
Measuring
cutting
the
2nd
flange
by…
Cutting
v
groove
on
front…
Grinding
Design
v
on
back
side,
to…
Grinding
Inspection
and
check
for…
Pre-clean
part
and
make
shine
Apply
dye
penetrant
Remove
penetrant
after
it
dry
Apply
developer
Evaluate…
Post-clean
part
Adjusting
two
flanges
to…
Inspection
Heating
front
side
of
bevel…
Welding
front
side
of
bevel…
Inspection
Rotate
flanges
to
back
sides
Adjust
it
on
the
bench
Remove
porosity
from
back…
Grind
depth
of
v
groove
Heating
backside
of
bevel…
Welding
back
side
of
bevel…
Inspection
Rotate
flanges
to
front
sides
Adjust
it
on
the
bench
Apply
heat
treatment
Inspection
Transport
it
to
the
cement…
Assemble
with
the
cement…
Tighten
all
bolts
control chart
Tmean Upper limit Lower limit median

34. Conclusion
 Based on Flange welding result , welding time and welding performance data
taken from maintenance time, that have indicated the company is indeed in
experiencing problems overall and the welding system is ineffective. This
project manage to bring out some of the causes of the ineffectiveness of the
flange maintenance and its welding, lack of welding maintenance policy on
work study
 The purpose of this project is to minimize or reduce the duration of flange
welding through work study guide lines and also to improve the welding
process and its activity, to reduce downtime