chapter 5 operational & maintenance skill...
TRANSCRIPT
97
Chapter 5
OPERATIONAL & MAINTENANCE SKILL DEVELOPMENT
5.1 INTRODUCTION
Training and development is vital for every organization to cope up with the
technological changes from time to time and to perform well. This helps in honing
skills, developing versatility and adaptability. Having a well designed approach
towards this is very important for every organization. Shirose et al. [2002] designed a
detailed education and training system describing its various levels as presented in
table 5.1.
Table 5.1 Education and training System [Shirose et al. 2002]
Levels On the job training Off the job training
Introduction Education on the job
(sectional education)
Guide to equipment maintenance (1)
Workshop exercise training
Quality control education (guide)
Developing basic
capability
Education on the job
(sectional education)
Guide to equipment maintenance (2)
Workshop exercise training
How to view drawings (2)
Quality control education (initial level)
Developing professional
capability
Education on the job
(sectional education)
Maintenance class (beginner's level)
Industrial engineering education (1)
Numerical control education
Quality control education (medium level)
Developing
management capability
Education on the job
(sectional education)
Maintenance class (Medium level)
Industrial engineering education (2)
Quality control education (higher level)
Developing advanced
management capability
Education on the job
(sectional education)
Maintenance class (Medium level)
Quality control circle leader education
(higher level)
The development of operational and maintenance skills of workmen is
described in the following sections.
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5.2 STEP 6: FORMULATION OF TRAINING POLICY AND CURRICULUM
Skill mapping exercise as presented in previous chapter the average skill
deficiencies in all skill attribute for workmen were worked out (presented in table
4.14 and figure 4.20). These skill deficiencies were adversely affecting the overall
performance of the manufacturing system (table 4.1 and 4.2). To bridge the skill gaps
of the workmen the following curriculum was developed -
(A) Off the job training
Training attributes common to all the H4 halogen bulb processing operators
1. Total productive maintenance
2. Autonomous maintenance
3. Quality maintenance.
4. Statistical quality control
5. Statistical process control
6. Q.C. tools
7. Connections of hydraulic and pneumatic pipes
8. Color coding of supply lines
9. Color coding of electrical connections
10. Methods of setting and taking reading with common gauges
11. Dealing with emergency
12. Safe operating conditions
13. 5S
Training attributes common to all the ball bearing processing operators
1. Total productive maintenance
2. Autonomous maintenance
3. Quality maintenance
4. Specifications of grinding wheel
5. Classifications of grinding wheel
6. Selection of grinding wheel
7. Glazing and loading of grinding wheel
8. Dressing of grinding wheel
9. Connections of hydraulic and pneumatic pipes
10. Color coding of supply lines
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11. Color coding of electrical connections
12. Methods of setting and taking reading with common gauges
13. Dealing with emergency
14. Safe operating conditions
15. 5S
16. Statistical quality control
17. Statistical process control
18. Q.C. tools
(B) On the job training
On the job training is imparted to improve following skills related to their
respective processes -
H4 bulb forming process
1. Method of setting L.P.G., Oxygen and Air pressure with the help of regulator.
2. Method of setting correct gas flame by flow meter.
3. Procedure of setting body tube length as per drawing and measurement.
4. Ways of checking form hole and length of the forming.
5. Methods of inspection of diameter of form hole for centering and ovality and
corrective actions for defects.
6. Procedure to conduct visual inspection of form shell for roundness and clarity
and corrective actions for defects.
7. Tips on how to check condition of ‘O' ring and forming wheel and corrective
actions, if warned out.
8. Identification of the condition of bearing jammed / cracked.
9. Detecting the effect of variation in glass tube material.
10. Indications of the condition of direct working of regulator which results in
increased gas pressure and correction.
11. Measure to be taken for safe working conditions.
H4 bulb jointing process
1. Method of setting L.P.G., Oxygen and Air pressure with the help of regulator.
2. Method of setting gas flame by flow meter.
3. Method of setting correct exhaust tube blow air stream pressure.
4. Procedure of loading exhaust tube and form tube on machine correctly.
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5. Ways of checking and setting dimensions of jointing as per drawing.
6. Method of inspection for straightness, leakage at joint, minimum hole
diameter and ring cut of jointing and corrective measures for non conformity.
7. Techniques of checking jointing for soundness of joint, no white particles on
jointing and no blow hole at joint and corrective actions for defects.
8. Methods of cleaning of machine and burners, lubrication & checking PVC
pipe condition.
9. Detection of the abnormal working of machine.
10. Identification of the condition of the bearing jammed / cracked.
11. Detecting the effect of variation in glass tube material
12. Measures to be taken for safe working.
H4 bulb sealing process
1. Method of setting L.P.G., Oxygen, Hydrogen and Air pressure with the help of
regulator.
2. Method of setting burner flame by flow meter.
3. Ways of checking pinch shape and corrective measures by setting punch
pressure / position and burner flame.
4. Method of checking filament mount for correct direction, no shift and no tilt
and corrective actions.
5. Procedure to check sealing stress, no bursting and no crack.
6. Method of setting correct vacuum level and detecting gas leakage and
corrective actions.
7. Methods of cleaning of machine and burners, lubrication & checking PVC /
metal pipe condition.
8. Detection of the abnormal working of machine.
9. Ways of identifying condition of the bearing jammed / cracked & checking up/
down movement of head and use of rustolene oil, if jammed.
10. Detection of the effect of variation in glass tube material.
11. Measures to be taken for safe working.
H4 bulb exhausting process
1. Method of setting L.P.G., Oxygen, Hydrogen and Air pressure with the help of
regulator.
2. Method of setting Nitrogen flow and Halogen gas mixture flow.
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3. Method of setting burner flame by flow meter.
4. Method of loading of sealing on machine.
5. Ways to check capsule shape & tip size and take corrective measures by
setting cutting burner flame.
6. Method of setting proper vacuum in machine & detecting gas leakage and
taking corrective actions.
7. Method of cleaning machine & burners, lubricating the moving parts &
checking PVC / metal pipe conditions.
8. Detection of the abnormal working of machine.
9. Method of identifying condition of the bearing jammed / cracked & checking
up / down movement of head and use of rustolene oil, if jammed.
10. Procedure of setting correct motions of mechanical links of the machine.
11. Measures to be taken for safe working.
Ball bearing face grinding process
1. Reading & understanding specifications of grinding wheel.
2. Procedure of installing and setting of grinding wheel.
3. Method of setting correct direction of wheel rotation.
4. Procedure to check dresser diamond condition.
5. Procedure of dressing of grinding wheel.
6. Method to prepare grinding machine for operation.
7. Method of checking plate condition and setting.
8. Checking hydraulic, pneumatic, mechanical links and electrical connections of
machine.
9. Method of setting and reading gauge for checking width size, width variation,
flatness, buckle, track circle out and squareness.
10. Method of visual inspection of work piece for black face, eccentric O.D.,
punch mark and chatter on face, after face grinding.
11. Identifying loading (exhausting) of grinding wheel.
12. Identifying exhausting of feed mechanism rings and procedure of changing it.
13. Method of oiling and greasing of machine.
14. Method of setting drop lubrication and oil/grease level.
15. Detecting abnormal sound / working of machine and remedy
16. Measures for safe working.
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17. Emergency and breakdown management.
Ball bearing outer diameter grinding process
1. Reading and understanding specifications of grinding wheel.
2. Method of installing and setting of grinding and regulating wheel.
3. Ways of checking dresser diamond condition.
4. Procedure of dressing of grinding / regulating wheel.
5. Preparing grinding machine for operation.
6. Method of checking plate condition and setting (Bottom/Top) as per job sizes.
7. How to check hydraulic, pneumatic, mechanical links and electrical
connections of machine.
8. Hydraulic and pneumatic connections (color coding of supply lines) and
mechanical links of machine and correct hydraulic oil level / air pressure.
9. Method of setting and reading gauges for checking outer diameter (O.D.) size,
surface taper, O.D. out of round, Jump and talyrond.
10. Method of visual inspection of work piece for black O.D., chatter on surface
and surface finish.
11. Identifying loading (exhausting) of grinding wheel.
12. Method of setting automatic feed rods of centreless grinding machine.
13. Procedure of oiling and greasing of machine.
14. Procedure of setting drop lubrication and oil/grease level.
15. Detection of abnormal sound / working of machine and its remedy
16. Measures for safe working.
17. Emergency and breakdown management.
Ball bearing IR / OR grinding lines
1. Method of mounting and setting of grinding wheel, dresser setting & dressing
of grinding wheel and preparing machine for operation.
2. Procedure of loading and unloading of work piece on machine center and
checking conveyor, sensor guided slide and push rod for correct working.
3. Hydraulic and pneumatic connections (color coding of supply lines) and
mechanical links of the machine.
4. Method of setting and reading gauges for checking track size, out of round,
wobble, TC out and curvature of track (for track grinding and honing of IR &
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OR) and knowledge of setting in process gauge for Track size (for track
grinding and honing of IR & OR).
5. Procedure for setting and reading gauges for checking bore size, out of round
& taper and setting in process gauge for bore size.
6. Interpretation of the results of the test performed in standard room about
roughness / telyrond / profile of track curvature / taper.
7. Corrective actions on the basis of the results of the standard room test.
8. Detection of exhausting of grinding wheel and abnormal sound / working of
machine.
9. Method of oiling and greasing of machine.
10. Procedure of lubrication of machine during operation.
11. Steps to be taken immediately after machine breakdown.
12. Measures to be adopted for safe working.
(C) One point lessons (OPL)
As discussed in chapter 2, one point lesson (OPL) is one of the most effective
methods of educating people focused on a single aspect of operating parameters and
methods of operating the equipment. This is a learning method frequently used by
workmen during daily work and daily meetings, lunch breaks etc. Each employee
come up with the ideas, discuss to make the issue more precise before preparation of
OPL. The OPL are prepared including visual images for better understanding of the
lesson. Numbers of one point lessons (74 nos.) were prepared to give learning to the
workmen of various training requirements related to their tasks. Few typical one point
lessons are presented here for illustration.
Illustrative one point lesson no. 1 is presented for the H4 forming process
which is prepared for training of skill attribute ‘D’ required for the process. During
study of the process it was observed that the operators of forming process are
expected to inspect the size of the forming using GO and NOGO gauges prepared
according to the designed size. On skill mapping of the workmen the skill deficiencies
were identified related to skill attribute ‘D’.
Illustrative one point lesson no.2 is presented for the H4 jointing process
which is prepared for training of skill ‘F’ required for the process. During study of the
process it was observed that the operators of jointing process are expected to visually
104
inspect the jointing for blow (glass) hole and crack at the joint of formed shell and
exhaust tube. On skill mapping of the workmen the skill deficiencies were identified
related to skill attribute ‘F’.
Illustrative one point lesson no.3 is presented for the IR/OR track grinding
process which is prepared for training of skill ‘A’ required for the process. During
study of the process it was observed that the operators of IR/OR grinding process are
expected to know the correct shape of the grinding wheel before it is mounted on the
spindle. On skill mapping of the workmen the skill deficiencies were identified
related to skill attribute ‘A’.
Illustrative one point lesson no.4 is presented for the IR/OR track grinding
process which is prepared for training of skill ‘A’. During study of the process it was
observed that the operators of IR/OR track grinding process are expected to correctly
shape the honing stone before it is mounted on the machine. On skill mapping of the
workmen the skill deficiencies were identified related to skill attribute ‘A’.
The respective operating executives and Setters (skilled operators) perform the
job of trainers, since, they are well qualified and knowledgeable about modern
manufacturing process and equipments and have vast exposure to the shop floor
practices. The setters of respective machines provide assistance during on the job
training.
Lesson plans and preparation of teaching materials
Excellent teaching methods were used, as discussed in previous pages to
implement education and training effectively. The self-enlightening training methods
were used and lesson plans were prepared in association with respective trainers for
each process / subject suitable for education and training. HRD division of concerned
companies helped in preparation of OPL and photograph for training.
Preparation of classrooms
Training activity was conducted on a one-on-one basis. A class size of 10-15
persons was organized. A room with a good environment, accommodating exercise
materials and slide display equipments, was used as class room. Company training
center was also well equipped with LCD projector, OHP and ergonomically design
seating arrangement necessary for effective training.
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5.3 STEP 7: EXECUTION OF OPERATIONAL AND MAINTENANCE SKILL
DEVELOPMENT
As discussed above, education and training was carried out with emphasis on
both theoretical (off the Job) and practical (on the Job) exercises. Due emphasis was
given on the following considerations during education and training activity -
Education and training activity was directly linked with actual work to
effectively implement the "bodily learning".
For each training unit, one-point lessons suitable for the actual workshop were
prepared, containing problems and improvement cases and used in education
and training, thus better results were achieved.
The duration of off the job training classes on each topic was 45 minutes and for on
the job training it was 30 minutes.
Fig 5.1 Education and training resource persons
Training resource persons
External faculty / experts Shift engineer
Off the job training On the job training
One point lessons
Shift supervisor
Setter
106
107
108
109
110
5.4 STEP 8: RE-SKILL MAPPING AND MEASUREMENT FOR
PERFORMANCE MEASUREMENT METRICS
The operational and maintenance skill development program was continued
for eight weeks. It was a rigorous exercise and supported whole heartedly by the
management and HRD in formulation of training policy and outsourcing general part
of the curriculum. It was also fully supported by engineers, supervisors and setters of
the companies to give valuable inputs for preparation of training curriculum and
executing it especially on the job. The workmen found it interesting and viewed it as a
key exercise in development of their skills. They were curious, supportive and
interactive all the way. To assess the effectiveness of the exercise the performance
measurement were taken.
The measurement taken were twofold i.e. operator skill levels and capability
indices Cp and Cpk were measured before training (presented in chapter 4) and after
completion of the training exercise whereas other performance measurement metrics
like Mean time between failures (MTBF), Mean time to repair (MTTR), Availability
rate, Performance rate, Quality rate, Overall equipment effectiveness (OEE), Overall
line effectiveness (OLE), Kaizen, Safety, health & environment events were
measured weekly. The weekly measurement were taken as 0 week (on the week the
performance was measured first time before start of the training program), -1week
(measurement for previous week of 0 week), 1 week (measurement after completion
of one week training), 2 week (measurement after completion of two week training)
and continued till 8 weeks completed. Their cumulative effect is presented in chapter
6 (results and discussion).
The re-skill mapping is presented in tables 5.2 (a-g) and spider charts prepared
after training are presented in figure 5.2 -5.8 (typical one spider chart is presented for
each process) in which blue line represents the desired skill levels, red line represents
skill level before training and the green line represents skill level after education and
training exercise. It is clear from the spider charts that skill levels of the workmen
have improved after training exercise.
111
Table 5.2 (a) Skill levels after training (H4 bulb forming process)
Sk
ill
att
rib
ute
s
Des
ired
sk
ill
lev
el
Skill gaps for
operators
FM01 FM02
A 3 O.K. O.K.
B 3 O.K. O.K.
C 3 O.K. O.K.
D 3 O.K. 3-2
E 3 3-2 O.K.
F 3 O.K. O.K.
G 3 O.K. 3-2
H 3 3-2 3-2
I 3 O.K. O.K.
J 3 O.K. O.K.
Operational / Maintenance skill attributes
A Ability to set correct L.P.G., Oxygen and Air pressure with the help of regulator.
B Ability to set gas flame by flow meter.
C Ability to measure and set up of body tube length as per drawing. Knowledge about loading
body tube on machine.
D Ability to check form hole size and formed shell length through GO and NO-GO gauges.
E Ability to check diameter for center and ovality. Ability of visual inspection for form shell
roundness and clarity.
F Ability to check 'O' ring, form wheel and cutter condition.
G Ability to detect condition of the bearing jammed / cracked.
H Ability to detect the effect of variation in glass tube material.
I Ability to identifying the condition of regulator direct (increased gas pressure) and correct it.
J Knowledge about measures to be taken for safe working.
112
Table 5.2 (b) Skill levels after training (H4 bulb jointing process)
Sk
ill
att
rib
ute
s
Des
ired
sk
ill
lev
el
Skill gaps for operators
JT01 JT02 JT03 JT04 JT05 JT06 JT07 JT08
A 3 O.K. O.K. O.K. O.K. 3-2 3-2 O.K. O.K.
B 3 O.K. O.K. 3-2 O.K. 3-2 3-2 O.K. O.K.
C 3 O.K. 3-2 3-2 O.K. 3-2 3-2 O.K. O.K.
D 3 O.K. 3-2 3-2 O.K. 3-2 3-2 O.K. O.K.
E 3 3-2 O.K. O.K. O.K. 3-2 3-2 O.K. 3-2
F 3 O.K. O.K. O.K. O.K. 3-2 3-1 O.K. O.K.
G 3 3-2 O.K. O.K. 3-2 3-1 3-2 O.K. O.K.
H 3 O.K. O.K. O.K. 3-2 3-2 3-2 3-2 3-2
I 3 3-2 O.K. 3-2 3-2 3-1 3-1 O.K. 3-2
J 3 O.K. O.K. O.K. O.K. O.K. 3-2 O.K. O.K.
Operational / Maintenance skill attributes
A Ability to set correct L.P.G., Oxygen and Air pressure with the help of regulator. Ability to set
gas flame by flow meter.
B Ability to set correctly exhaust tube blow air stream pressure.
C Knowledge about loading exhaust tube and formed tube on machine correctly.
D Ability to check and set dimensions of jointing as per drawing.
E Ability to check straightness of jointing, leakage at joint, minimum jointing hole and ring cut
of jointing.
F Ability to check jointing for sound solidity, no white particles on jointing and no glass bubble
at joint.
G Ability to clean machine & burners, lubricate the moving parts & check PVC pipe condition
and identify the abnormal working of machine.
H Ability to detect the condition of the bearing jammed / cracked.
I Ability to understand the effect of variation in glass tube material.
J Knowledge about measures to be taken for safe working.
113
Table 5.2 (c) Skill levels after training (H4 sealing process)
Sk
ill
att
rib
ute
s
Des
ired
sk
ill
lev
el Skill gaps for operators
SL01 SL02 SL03 SL04 SL05 SL06 SL07 SL08
A 3 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
B 3 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
C 3 O.K. O.K. O.K. O.K. 3-2 O.K. 3-2 3-2
D 3 O.K. 3-2 3-2 O.K. 3-2 O.K. 3-2 3-2
E 3 O.K. O.K. 3-2 O.K. 3-2 O.K. 3-2 3-2
F 3 O.K. O.K. O.K. O.K. O.K. O.K. O.K. 3-2
G 3 O.K. 3-2 O.K. 3-2 3-2 O.K. O.K. 3-2
H 3 O.K. O.K. 3-2 3-2 O.K. O.K. O.K. O.K.
I 3 3-2 3-2 3-2 3-2 3-2 O.K. O.K. 3-2
J 3 O.K. 3-2 O.K. O.K. 3-2 O.K. O.K. O.K.
Operational / Maintenance skill attributes
A Ability to set correct L.P.G., Oxygen, Hydrogen and Air pressure with the help of regulator.
B Ability to set burner flame by flow meter.
C Knowledge about loading of Jointing and mount on machine.
D Ability to check pinch shape and take corrective measures by setting punch pressure / position
and burner flame.
E Ability to check mount for correct direction, no shift and tilt. Ability to check for sealing
stress, no bursting and no crack.
F Ability to check proper vacuum in machine and gas leakage, if any.
G Ability to clean machine & burners, lubricate the moving parts & check PVC pipe condition
and identify the abnormal working of machine.
H Ability to detect condition of the bearing jammed / cracked. Ability to check head up / down
movement and use of rustolene oil, if jammed.
I Ability to understand the effect of variation in glass tube material.
J Knowledge about measures to be taken for safe working.
114
Table 5.2 (d) Skill levels after training (H4 exhausting process)
Sk
ill
att
rib
ute
s
Des
ired
sk
ill
lev
el Skill gaps for operators
EH01 EH02 EH03 EH04 EH05 EH06 EH07 EH08 EH09 EH10 EH11 EH12
A 3 O.K. O.K. O.K. O.K. O.K. O.K. O.K. 3-2 3-2 3-2 O.K. 3-2
B 3 O.K. O.K. O.K. O.K. O.K. O.K. O.K. 3-2 O.K. 3-2 O.K. 3-2
C 3 O.K. 3-2 3-2 O.K. 3-2 O.K. O.K. O.K. 3-2 O.K. O.K. O.K.
D 3 O.K. O.K. O.K. 3-2 O.K. O.K. 3-2 O.K. 3-1 3-2 3-2 3-2
E 3 3-2 3-2 O.K. O.K. 3-2 O.K. O.K. 3-2 3-2 O.K. 3-2 3-2
F 3 O.K. 3-2 3-2 O.K. O.K. O.K. O.K. 3-2 O.K. O.K. O.K. 3-2
G 3 O.K. 3-2 3-2 O.K. O.K. 3-2 3-2 O.K. 3-2 3-2 O.K. 3-2
H 3 3-2 O.K. 3-2 3-2 O.K. O.K. O.K. O.K. 3-2 O.K. O.K. 3-2.
I 3 O.K. 3-2 3-2 O.K. O.K. 3-2 3-2 3-2 3-2 3-2 3-2 3-2
J 3 O.K. O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
Operational / Maintenance skill attributes
A Ability to set correct L.P.G., Oxygen, Hydrogen and Air pressure with the help of regulator. Ability
to set Nitrogen flow and Halogen gas mixture flow.
B Ability to set burner flame by flow meter.
C Knowledge about loading of sealing on machine.
D Ability to check capsule shape & tip size and take corrective measures by setting cutting burner
flame.
E Ability to check sealing for leakage and black glass. Ability to check capsule for no bursting and no
crack.
F Ability to check proper vacuum in machine & gas leakage and take corrective actions.
G Ability to clean machine & burners, lubricate the moving parts & check PVC pipe condition and
identify the abnormal working of machine.
H Condition of the bearing jammed / cracked. Head up and down and use of rustolene oil if jammed.
I Ability to set motion of mechanical links of machine.
J Knowledge about measures to be taken for safe working.
115
Table 5.2 (e) Skill levels after training (ball bearing face grinding process)
Sk
ill
Att
rib
ute
s
Des
ired
sk
ill
lev
el
Skill gaps for operators
FG01 FG02 FG03 FG04 FG05 FG06 FG07 FG08 FG09 FG10 FG11 FG12
A 3 O.K. O.K. 3-1 O.K. O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K.
B 3 O.K. O.K. 3-2 O.K. O.K. 3-2 O.K. O.K. O.K. 3-2 O.K. O.K.
C 3 O.K. O.K. 3-1 O.K. O.K. O.K. 3-2 O.K. O.K. 3-2 O.K. 3-2
D 3 O.K. O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K. 3-2 3-2 O.K.
E 3 O.K. O.K. 3-2 O.K. O.K. 3-2 3-2 O.K. O.K. O.K. O.K. O.K.
F 3 O.K. O.K. 3-2 O.K. O.K. 3-2 O.K. O.K. O.K. 3-2 3-2 O.K.
G 3 O.K. O.K. 3-2 O.K. O.K. 3-2 O.K. O.K. O.K. 3-2 O.K 3-2
H 3 O.K. O.K. 3-1 O.K. O.K. O.K. 3-2 O.K. O.K. 3-2 3-2 O.K.
I 3 O.K. O.K. 3-1 O.K. O.K. 3-2 O.K. O.K. O.K. 3-2 O.K. O.K.
J 3 O.K. O.K. 3-2 O.K. O.K. 3-2 3-2 O.K. O.K. 3-2 O.K. O.K.
Operational / Maintenance skill attribute
A Knowledge about installing and setting of grinding wheel and direction of wheel rotation and
specification of wheel.
B Knowledge about dressing and preparing grinding wheels (machine) for operation and checking
diamond condition.
C Knowledge about plate setting & plate condition.
D Knowledge about hydraulic and pneumatic connections (color coding of supply lines) and
mechanical links of the machine.
E Knowledge about setting and reading gauge for checking Width size, width variation, flatness,
buckle, T.C. out and squareness.
F Knowledge about visual inspection of work piece for black face, eccentric O.D., punch mark and
chatter on face, after face grinding.
G Awareness about exhausting of grinding wheel and feed mechanism rings and abnormal sound /
working of the machine.
H Knowledge about cleaning work place and cleaning, oiling and greasing of machine and drop
lubrication and oil/grease level.
I Knowledge about steps to be taken immediately after machine breakdown.
J Knowledge about measures to be adopted for safe working.
116
Table 5.2 (f) Skill levels after training (ball bearing OD grinding process)
Contd…
Operational / Maintenance skill attribute
A Knowledge about installing and setting of grinding as well as regulating wheel and specification of
grinding wheel.
B Knowledge about dressing of grinding / regulating wheel and preparing (setting) machine for
operation.
C Knowledge about plate setting (Bottom & Top) for different job sizes and plate condition.
D Knowledge about hydraulic and pneumatic connections (color coding of supply) and mechanical
links of the machine and hydraulic oil level / air pressure etc.
E Knowledge about setting and reading gauges for checking O.D. size, taper, O.D. out of round, Jump
and talyrond.
F Knowledge about visual inspection of work piece for black O.D., chatter, surface finish etc.
G Awareness about exhausting of grinding / regulating wheel and abnormal sound / working of the
machine.
H Knowledge about cleaning work place and cleaning, oiling and greasing of machine and drop
lubrication and oil/grease level.
I Knowledge about steps to be taken immediately after machine breakdown
J Knowledge about measures to be adopted for safe working.
Sk
ill
att
rib
ute
Des
ired
sk
ill
lev
el
Skill gaps for operators
OD01 OD02 OD03 OD04 OD05 OD06 OD07 OD08 OD09 OD10 OD11 OD12
A 3 3-2 3-2 3-2 O.K. O.K. O.K. O.K. 3-2 O.K. O.K. O.K. O.K.
B 3 3-1 3-2 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. 3-2
C 3 3-2 O.K. O.K. O.K. O.K. O.K. O.K. 3-2 3-2 O.K. O.K. O.K.
D 3 3-1 3-2 3-2 O.K. O.K. O.K. 3-2 3-2 O.K. O.K. O.K. 3-2
E 3 O.K. 3-2 3-2 O.K. 3-2 O.K. O.K. 3-2 O.K. O.K. O.K. O.K.
F 3 3-2 3-2 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
G 3 3-2 O.K. 3-2 3-2 O.K. 3-2 3-2 3-2 3-2 O.K. 3-2 O.K.
H 3 3-2 3-2 O.K. O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K.
I 3 O.K. O.K. 3-1 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
J 3 O.K. 3-2 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
117
…Contd.
Table 5.2 (f) Skill levels after training (ball bearing OD grinding process) S
kil
l a
ttri
bu
tes
Des
ired
sk
ill
lev
el
Skill gaps for operators
OD13 OD14 OD15 OD16 OD17 OD18 OD19 OD20 OD21 OD22 OD23 OD24
A 3 3-2 O.K O.K. O.K. 3-2 O.K. 3-2 O.K. 3-1 O.K. 3-2 3-2
B 3 3-2 O.K. O.K. O.K. 3-2 O.K. O.K. 3-2 3-1 O.K. O.K. 3-2
C 3 3-2 O.K. O.K. 3-2 3-2 O.K. O.K. O.K. 3-2 O.K. 3-2 3-2
D 3 3-2 3-2 O.K. O.K. 3-2 O.K. 3-2 O.K. 3-2 O.K. 3-2 3-2
E 3 3-2 3-2 O.K. 3-2 3-2 O.K. O.K. O.K. 3-1 O.K. 3-2 3-2
F 3 3-2 O.K. O.K. O.K. 3-2 O.K. O.K. O.K. 3-1 O.K. 3-2 3-2
G 3 3-2 O.K. O.K. 3-2 3-2 O.K. 3-2 3-2 3-2 O.K. O.K. 3-2
H 3 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. 3-2 O.K. 3-2 3-2
I 3 3-2 O.K. O.K. 3-2 O.K. O.K. 3-2 O.K. 3-2 O.K. 3-2 3-2
J 3 3-2 O.K. 3-2 O.K. 3-2 O.K. 3-2 3-2 3-2 O.K. O.K. 3-2
118
Table 5.2 (g) Skill levels after training (ball bearing IR/OR grinding lines)
Sk
ill
att
rib
ute
s
Des
ired
sk
ill
lev
el
Skill gaps for operators
GL01 GL02 GL03 GL04 GL05 GL06 GL07 GL08 GL09 GL10 GL11 GL12
A 3 O.K. O.K. 3-2 O.K. O.K. O.K. O.K. O.K. 3-2 O.K. O.K. O.K.
B 3 O.K. 3-2 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
C 3 O.K. 3-2 3-2 O.K. O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K.
D 3 O.K. 3-2 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
E 3 O.K. O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. 3-2
F 3 3-2 3-2 3-2 O.K. 3-2 3-2 O.K. O.K. 3-2 3-2 O.K. 3-2
G 3 O.K. O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
H 3 3-2 3-2 3-2 O.K. O.K. 3-2 O.K. O.K. 3-2 O.K. O.K. O.K.
I 3 O.K. O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
J 3 O.K. O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
Operational / Maintenance skill attributes
A Knowledge about mounting and setting of grinding wheel, diamond condition and dresser setting
& dressing of grinding wheel and preparing the machine for operation.
B
Knowledge about loading and unloading of work piece on machine center and working of
conveyor (working of sensor guided slide / push rod / equipments etc.)and knowledge about
hydraulic and pneumatic connections ( color coding of supply lines ) and mechanical links of the
machine.
C
Knowledge about setting and reading gauges for checking Track size, out of round, wobble, TC
out and curvature of track (for track grinding and honing of IR & OR) and knowledge of setting
in process gauge for track size (track grinding of IR & OR).
D Knowledge about setting and reading gauges for checking Bore size, Out of round and taper and
knowledge of setting in process gauge for bore size.
E Ability to Interpret the results of the test performed in standard room about roughness / telyrond /
profile of track curvature / Taper.
F Ability to take corrective actions, if needed.
G Awareness about exhausting of grinding wheel and abnormal sound / working of the machine.
H Knowledge about cleaning work place and cleaning, oiling and greasing of machine and drop
lubrication of m/c during operation.
I Knowledge about steps to be taken immediately after machine breakdown.
J Knowledge about measures to be adopted for safe working.
Contd…
119
…Contd.
Table 5.2 (g) Skill levels after training (ball bearing IR/OR grinding lines)
S
kil
l
att
rib
ute
s
Des
ired
sk
ill
lev
el
Skill gaps for operators
GL13 GL14 GL15 GL16 GL17 GL18 GL19 GL20
A 3 O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K.
B 3 O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K.
C 3 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
D 3 O.K. O.K. O.K. O.K. 3-2 O.K. O.K. O.K.
E 3 O.K. O.K. O.K. O.K. O.K. 3-2 O.K. O.K.
F 3 O.K. O.K. O.K. O.K. O.K. 3-2 O.K. O.K.
G 3 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
H 3 O.K. 3-2 O.K. O.K. O.K. O.K. O.K. O.K.
I 3 3-2 O.K. O.K. O.K. O.K. O.K. O.K. 3-2
J 3 O.K. O.K. O.K. O.K. O.K. O.K. O.K. O.K.
120
121
122
123
124
125
126
127
5.5 COMPARISON OF SKILL LEVELS BEFORE AND AFTER TRAINING
The comparison between skill gaps before and after training for the workmen
is presented in table 5.3 and figure 5.9 which show a significant improvement in the
skills of the workmen. The observations for calculation of capability indices Cp and
Cpk after training are presented in tables 5.4 (a-h) for various processes under study
and corresponding X-bar chart, R-chart and histogram are presented in figures 5.10
(a-c) to 5.17 (a-c). The calculated values of capability indices Cp and Cpk are
presented in the tables 5.5 to 5.12.
The measurements for performance measurement metrics MTBF, MTTR,
availability rate, performance rate, quality rate, OEE, Kaizen and SHE issues are
presented in tables 5.13, 5.14, 5.15, 5.18, 5.19, 5.20, 5.21 and 5.22 respectively. The
actual production v/s target production and rejection v/s actual production is presented
in tables 5.16 and 5.17 respectively.
Table 5.3 Comparison of skill levels before and after training
Processes
Average skill
deficiencies in all the
skill attributes for a
workman
(before training)
Average skill
deficiencies in all
the skill attributes
for a workman
(after training)
% improvement
H4 forming 10 3.5 65%
H4 jointing 14 4.875 65.17%
H4 sealing 11.125 3.375 69.66%
H4 exhausting 12.667 4.25 66.45%
Ball bearing face
grinding 8.58 3.08 64.10%
Ball bearing OD
grinding 11.125 4.375 60.67%
Ball bearing IR/OR
grinding lines 6.05 1.75 71.07%
128
Fig 5.9 Comparison of skill levels before and after training
10
14
11.125
12.667
8.58
11.125
6.05
3.5
4.875
3.375
4.25
3.08
4.375
1.75
0
2
4
6
8
10
12
14
16
Comparison of skill levels before and after training
Average skill deficiencies in all the
skill attributes for a workman
(before training)
Average skill deficiencies in all the
skill attributes for a workman (after
training)
129
130
131
132
133
134
135
136
137
Fig. 5.10 (a) X-Bar chart (Forming process)
Fig. 5.10 (b) R-Bar chart (Forming process)
Fig. 5.10 (c) Histogram (Forming process)
Table 5.5 Capability indices (Forming process) after training
USL LSL Cp Cpk
44.50 mm 43.50 mm 1.50 1.28
43.8200
43.9200
44.0200
44.1200
44.2200
44.3200
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Av
erag
e
Sub group no.
X -Bar chart (after training)
H4 forming process
0.0000
0.1000
0.2000
0.3000
0.4000
0.5000
0.6000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Ra
ng
e
Sub group no.
R-chart (after training)
H4 forming process
0
10
20
30
40
43.125 43.25 43.375 43.5 43.625 43.75 43.875 44 44.125 44.25 44.375 44.5 44.625 44.75 44.875
Fre
qu
ency
Histogram - H4 forming process (after training)
138
Fig. 5.11 (a) X-Bar chart (Jointing process)
Fig. 5.11 (b) R-Bar chart (Jointing process)
Fig. 5.11 (c) Histogram (Jointing process)
Table 5.6 Capability indices (Jointing process) after training
USL LSL Cp Cpk
84.00 mm 82.00 mm 2.62 2.38
82.8400
82.9400
83.0400
83.1400
83.2400
83.3400
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Av
erag
e
Sub group no.
X-bar chart (after training)
H4 jointing process
0.0000
0.2000
0.4000
0.6000
0.8000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Ra
ng
e
Sub group no.
R-chart (after training)
H4 jointing process
0
20
40
60
80
81.25 81.5 81.75 82 82.25 82.5 82.75 83 83.25 83.5 83.75 84 84.25 84.5 84.75
Fre
qu
ency
Histogram - H4 jointing process (after training)
139
Fig. 5.12 (a) X-Bar chart (Sealing process)
Fig. 5.12 (b) R-Bar chart (Sealing process)
Fig. 5.12 (c) Histogram (Sealing process)
Table 5.7 Capability indices (Sealing process) after training
USL LSL Cp Cpk
15.50 mm 15.30 mm 1.60 1.54
15.3600
15.3700
15.3800
15.3900
15.4000
15.4100
15.4200
15.4300
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Av
erag
e
Sub group no.
X-bar chart (after training)
H4 sealing process
0.0000
0.0200
0.0400
0.0600
0.0800
0.1000
0.1200
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Ra
ng
e
Sub group no.
R- chart (after training)
H4 sealing process
0
10
20
30
40
50
60
15.225 15.25 15.275 15.3 15.325 15.35 15.375 15.4 15.425 15.45 15.475 15.5 15.525 15.55 15.575
Fre
qu
ency
Histogram - H4 sealing process (after training)
140
Fig. 5.13 (a) X-Bar chart (Exhausting process)
Fig. 5.13 (b) R-Bar chart (Exhausting process)
Fig. 5.13 (c) Histogram (Exhausting process)
Table 5.8 Capability indices (Exhausting process) after training
USL LSL Cp Cpk
6.50 mm 5.50 mm 2.22 2.09
11.9948
11.9953
11.9958
11.9963
11.9968
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Av
erag
e
Sub group no.
X -Bar chart (after training)
H4 exhausting process
0.0000
0.0005
0.0010
0.0015
0.0020
0.0025
0.0030
0.0035
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Ra
ng
e
Sub group no.
R-chart (after training)
H4 exhausting process
0
10
20
30
40
50
60
70
11.99075 11.9915 11.99225 11.993 11.99375 11.9945 11.99525 11.996 11.99675 11.9975 11.99825 11.999 11.99975 12.0005 12.00125
Fre
qu
ency
Histogram - H4 exhausting process (after training)
141
Fig. 5.14 (a) X-Bar chart (Face grinding process)
Fig. 5.14 (b) R-Bar chart (Face grinding process)
Fig. 5.14 (c) Histogram (Face grinding process)
Table 5.9 Capability indices (Face grinding process) after training
USL LSL Cp Cpk
9.99 mm 9.95 mm 1.46 1.44
11.9946
11.9951
11.9956
11.9961
11.9966
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Av
erag
e
Sub group no.
X -Bar chart (after training)
Face grinding process
0.0000
0.0005
0.0010
0.0015
0.0020
0.0025
0.0030
0.0035
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Ra
ng
e
Sub group no.
R-chart (after training)
Face grinding process
0
10
20
30
40
50
60
70
11.99075 11.9915 11.99225 11.993 11.99375 11.9945 11.99525 11.996 11.99675 11.9975 11.99825 11.999 11.99975 12.0005 12.00125
Fre
qu
ency
Histogram -Face grinding process (after training)
142
Fig. 5.15 (a) X-Bar chart (OD grinding process)
Fig. 5.15 (b) R-Bar chart (OD grinding process)
Fig. 5.15 (c) Histogram (OD grinding process)
Table 5.10 Capability indices (OD grinding process) after training
USL LSL Cp Cpk
31.999 mm 31.990 mm 2.02 1.75
11.9948
11.9953
11.9958
11.9963
11.9968
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Av
erag
e
Sub group no.
X -Bar chart (after training)
OD grinding process
0.0000
0.0010
0.0020
0.0030
0.0040
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Ra
ng
e
Sub group no.
R-chart (after training)
OD grinding process
0
10
20
30
40
50
60
70
11.99075 11.9915 11.99225 11.993 11.99375 11.9945 11.99525 11.996 11.99675 11.9975 11.99825 11.999 11.99975 12.0005 12.00125
Fre
qu
ency
Histogram - OD grinding process (after training)
143
Fig. 5.16 (a) X-Bar chart (OR grinding line)
Fig. 5.16 (b) R-Bar chart (OR grinding line)
Fig. 5.16 (c) Histogram (OR grinding line)
Table 5.11 Capability indices (OR grinding line) after training
USL LSL Cp Cpk
28.036 mm 27.986 mm 3.74 3.49
11.9948
11.9953
11.9958
11.9963
11.9968
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Av
erag
e
Sub group no.
X -Bar chart (after training)
OR grinding line
0.0000
0.0010
0.0020
0.0030
0.0040
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Ra
ng
e
Sub group no.
R-chart (after training)
OR grinding line
0
10
20
30
40
50
60
70
11.99075 11.9915 11.99225 11.993 11.99375 11.9945 11.99525 11.996 11.99675 11.9975 11.99825 11.999 11.99975 12.0005 12.00125
Fre
qu
ency
Histogram -OR grinding line
144
Fig. 5.17 (a) X-Bar chart (IR grinding line)
Fig. 5.17 (b) R-Bar chart (IR grinding line)
Fig. 5.17 (c) Histogram (IR grinding line)
Table 5.12 Capability indices (IR grinding line) after training
USL LSL Cp Cpk
11.999 mm 11.993 mm 1.49 1.41
11.9948
11.9953
11.9958
11.9963
11.9968
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Av
erag
e
Sub group no.
X -Bar chart (after training)
IR grinding line
0.0000
0.0005
0.0010
0.0015
0.0020
0.0025
0.0030
0.0035
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Ra
ng
e
Sub group no.
R-chart (after training)
IR grinding line
0
10
20
30
40
50
60
70
11.99075 11.9915 11.99225 11.993 11.99375 11.9945 11.99525 11.996 11.99675 11.9975 11.99825 11.999 11.99975 12.0005 12.00125
Nu
mb
er
Histogram - IR grinding line (after training)
145
Table 5.13 Mean time between failures (MTBF)
Processes
Week-wise MTBF (in days)
-1 0 1 2 3 4 5 6 7 8
H4 forming 2.33 1.75 2.33 2.33 3.5 3.5 2.33 3.5 3.5 3.5
H4 jointing 1.75 2.33 2.33 2.33 3.5 2.33 3.5 3.5 3.5 7
H4 sealing 1.75 1.4 2.33 2.33 2.33 3.5 3.5 2.33 3.5 3.5
H4 exhausting 1.75 1.75 1.75 2.33 1.75 2.33 2.33 2.33 2.33 3.5
Ball bearing
face grinding 0.875 0.875 1 1.116 1 1.75 1.4 1.4 1.75 1.75
Ball bearing OD
grinding 1.116 1 1.116 1.75 2.333 1.75 2.333 2.333 3.5 3.5
Ball bearing IR
grinding lines 0.7 0.777 0.777 1 0.875 1 1 1.116 1.4 1.4
Ball bearing OR
grinding lines 0.777 0.636 0.875 1.116 1 1.116 1.4 1.75 1.4 1.75
146
Table 5.14 Mean time to repair (MTTR)
Processes
Week-wise MTTR in hrs.
-1 0 1 2 3 4 5 6 7 8
H4 forming 1.5 1.5 1.25 1.25 1.25 1.75 1.25 1.5 1 1
H4 jointing 1.5 1.75 1.5 1.25 1.25 1.25 1.25 1 1 1
H4 sealing 1.25 1 1 0.8 1.2 0.75 0.75 0.75 0.75 0.75
H4 exhausting 1.5 1.5 1.25 1 1.25 1 1 1 1 1
Ball bearing
face grinding 1.6 1.6 1.35 1.6 1.433 1.1 1.1 1.233 1.1 1.0
Ball bearing
OD grinding 1.833 1.6 1.533 1.4 1.25 1.33 1.25 1.25 1.15 1.083
Ball bearing
IR grinding
lines
1.5 1.5 1.333 1.25 1.166 1.25 1.0 1.0 0.833 0.75
Ball bearing
OR grinding
lines
1.5 1.4 1.4 1.333 1.25 1.2 1.166 1.0 0.75 0.833
147
Table 5.15 Availability rate
Processes
Week-wise availability rate
-1 0 1 2 3 4 5 6 7 8
H4 forming 0.903 0.89 0.911 0.918 0.922 0.924 0.923 0.932 0.939 0.939
H4 jointing 0.903 0.908 0.916 0.918 0.927 0.924 0.931 0.937 0.936 0.939
H4 sealing 0.90 0.90 0.916 0.923 0.916 0.936 0.94 0.936 0.942 0.941
H4 exhausting 0.907 0.908 0.915 0.927 0.915 0.931 0.931 0.932 0.933 0.94
Ball bearing
face grinding 0.673 0.655 0.675 0.689 0.690 0.736 0.729 0.735 0.755 0.763
Ball bearing
OD grinding 0.684 0.691 0.730 0.751 0.752 0.767 0.769 0.765 0.804 0.798
Ball bearing
IR grinding
lines
0.910 0.919 0.927 0.947 0.944 0.948 0.957 0.964 0.975 0.977
Ball bearing
OR grinding
lines
0.918 0.908 0.933 0.952 0.947 0.957 0.965 0.976 0.977 0.980
148
Table 5.16 Week-wise production (target / actual) (units)
Processes Week-wise production (units)
-1 0 1 2 3 4 5 6 7 8
H4 forming Actual 157495 155367 161362 168836 169105 171911 169525 174009 175255 175586
Target 182160 180240 181500 185100 186000 186000 183900 187800 189396 189396
H4 jointing Actual 77750 79325 82232 84316 86142 85958 87850 89128 87810 89233
Target 127500 129752 130900 131112 130900 131962 133025 133875 132175 134155
H4 sealing Actual 74112 72318 77895 81796 82206 83440 84574 84891 85757 84610
Target 128605 127075 130900 131835 130815 132175 134300 133662 134580 132880
H4
exhausting
Actual 73650 73323 74952 78014 80530 83134 82668 82028 83445 83188
Target 114375 114502 115350 115500 115350 117375 117375 116122 117622 118500
Ball bearing
face grinding
Actual 246020 239107 246202 250738 260612 279836 278511 276452 288592 291816
Target 346505 336863 347117 350178 354981 378645 375278 373549 388287 392726
Ball bearing
OD grinding
Actual 164452 164122 176808 183677 184897 185814 189721 189956 199378 196523
Target 219768 219382 234483 241359 241645 243518 246996 245659 258176 253176
Ball bearing
IR grinding
lines
Actual 43905 44183 46872 46905 48370 48316 48800 50174 52297 53542
Target 60894 61491 62293 63381 63151 63381 63282 64476 65206 65371
Ball bearing
OR grinding
lines
Actual 44185 44598 46355 48276 48087 49056 50016 50488 52177 53079
Target 60695 60734 62406 63687 62585 63998 64543 65272 64575 65537
149
Table 5.17 Week-wise production / rejection (units)
Processes Week-wise production (units)
-1 0 1 2 3 4 5 6 7 8
H4 forming Rejection 1876 1762 1812 1773 1677 1153 1004 1014 1136 923
Actual
production 157495 155367 161362 168836 169105 171911 169525 174009 175255 175586
H4 jointing Rejection 724 756 652 705 655 623 609 651 559 565
Actual
production 77750 79325 82232 84316 86142 85958 87850 89128 87810 89233
H4 sealing Rejection 1074 1010 972 930 808 868 732 721 639 552
Actual
production 74112 72318 77895 81796 82206 83440 84574 84891 85757 84610
H4
exhausting
Rejection 1168 1182 1084 991 1089 1022 880 832 739 699
Actual
production 73650 73323 74952 78014 80530 83134 82668 82028 83445 83188
Ball bearing
face grinding
Rejection 378 356 342 304 328 261 234 195 167 163
Actual
production 246020 239107 246202 250738 260612 279836 278511 276452 288592 291816
Ball bearing
OD grinding
Rejection 232 248 227 199 184 158 155 134 120 118
Actual
production 164452 164122 176808 183677 184897 185814 189721 189956 199378 196523
Ball bearing
IR grinding
lines
Rejection 74 81 73 61 63 52 46 48 42 40
Actual
production 43905 44183 46872 46905 48370 48316 48800 50174 52297 53542
Ball bearing
OR grinding
lines
Rejection 76 74 65 70 64 49 42 43 39 35
Actual
production 44185 44598 46355 48276 48087 49056 50016 50488 52177 53079
150
Table 5.18 Performance rate
Processes
Week-wise performance rate
-1 0 1 2 3 4 5 6 7 8
H4 forming 0.864 0.862 0.889 0.912 0.909 0.924 0.921 0.926 0.925 0.927
H4 jointing 0.609 0.611 0.628 0.643 0.658 0.651 0.660 0.665 0.664 0.665
H4 sealing 0.576 0.569 0.595 0.620 0.628 0.631 0.629 0.635 0.637 0.636
H4 exhausting 0.643 0.640 0.649 0.675 0.698 0.708 0.704 0.706 0.709 0.702
Ball bearing
face grinding 0.71 0.709 0.709 0.716 0.734 0.739 0.742 0.74 0.743 0.743
Ball bearing
OD grinding 0.748 0.748 0.754 0.761 0.765 0.763 0.768 0.773 0.772 0.776
Ball bearing
IR grinding
lines
0.721 0.718 0.752 0.74 0.765 0.762 0.771 0.778 0.802 0.819
Ball bearing
OR grinding
lines
0.727 0.734 0.742 0.758 0.768 0.766 0.774 0.773 0.808 0.809
151
Table 5.19 Quality rate
Processes
Week-wise quality rate
-1 0 1 2 3 4 5 6 7 8
H4 forming 0.988 0.988 0.988 0.989 0.990 0.993 0.994 0.994 0.993 0.994
H4 jointing 0.990 0.990 0.992 0.991 0.992 0.992 0.993 0.992 0.993 0.993
H4 sealing 0.985 0.986 0.987 0.988 0.990 0.989 0.991 0.991 0.992 0.993
H4 exhausting 0.984 0.983 0.985 0.987 0.986 0.987 0.989 0.989 0.991 0.991
Ball bearing
face grinding 0.9984 0.9985 0.9986 0.9987 0.9987 0.999 0.9991 0.9992 0.9994 0.9994
Ball bearing
OD grinding 0.9985 0.9984 0.9987 0.9989 0.999 0.9991 0.9991 0.9992 0.9993 0.9993
Ball bearing
IR grinding
lines
0.9983 0.9981 0.9984 0.9986 0.9986 0.9989 0.9990 0.9990 0.9991 0.9992
Ball bearing
OR grinding
lines
0.9982 0.9983 0.9985 0.9985 0.9986 0.9990 0.9991 0.9991 0.9992 0.9993
152
Table 5.20 Overall equipment effectiveness
Processes
Week-wise overall equipment effectiveness
-1 0 1 2 3 4 5 6 7 8
H4 forming 0.77 0.757 0.8 0.828 0.829 0.847 0.844 0.857 0.862 0.865
H4 jointing 0.544 0.549 0.57 0.584 0.605 0.596 0.61 0.618 0.617 0.62
H4 sealing 0.51 0.504 0.537 0.565 0.569 0.584 0.585 0.589 0.595 0.594
H4 exhausting 0.573 0.571 0.584 0.617 0.629 0.65 0.648 0.65 0.655 0.653
Ball bearing
face grinding 0.477 0.463 0.477 0.492 0.505 0.543 0.54 0.543 0.56 0.566
Ball bearing
OD grinding 0.51 0.516 0.549 0.57 0.574 0.584 0.59 0.59 0.62 0.618
Ball bearing
IR grinding
lines 0.654 0.658 0.695 0.699 0.721 0.721 0.737 0.749 0.781 0.799
Ball bearing
OR grinding
lines 0.666 0.665 0.691 0.72 0.726 0.732 0.746 0.753 0.788 0.792
153
Table 5.21 Kaizen
Processes Fortnightly kaizen
-1 0 1 2 3 4
H4 forming 0 2 4 5 6 6
H4 jointing 1 1 2 6 5 6
H4 sealing 2 1 3 5 5 5
H4 exhausting 1 2 4 4 5 6
Ball bearing face
grinding 3 4 4 6 5 8
Ball bearing OD
grinding 6 5 7 9 8 10
Ball bearing IR/OR
grinding lines 2 4 5 7 7 7
Table 5.22 Safety, health and environment issues
Processes
Fortnightly safety health and environment
-1 0 1 2 3 4
H4 forming 6 6 4 5 3 2
H4 jointing 5 4 3 3 2 2
H4 sealing 6 5 4 4 2 1
H4 exhausting 6 7 5 5 4 2
Ball bearing face
grinding 4 3 2 1 2 1
Ball bearing OD
grinding 3 3 2 2 2 1
Ball bearing IR
grinding lines 3 5 2 2 1 1
Ball bearing OR
grinding lines 3 2 2 1 1 1
Based on data related to the performance measurement metrics furnished in
the tables 5.13 - 5.15 and tables 5.18 - 5.22 the charts were prepared which are
presented as figure 5.10 – 5.17.
154
(a)
(b)
(c)
-1 0 1 2 3 4 5 6 7 8
MTBF 2.33 1.75 2.33 2.33 3.5 3.5 2.33 3.5 3.5 3.5
0
1
2
3
4
MT
BF
(Day
s)
Weeks
MTBF
H4 forming process
-1 0 1 2 3 4 5 6 7 8
MTBF 1.75 2.33 2.33 2.33 3.5 2.33 3.5 3.5 3.5 7
0
2
4
6
8
MTB
F (D
ays)
Weeks
MTBF
H4 jointing process
-1 0 1 2 3 4 5 6 7 8
MTBF 1.75 1.4 2.33 2.33 2.33 3.5 3.5 2.33 3.5 3.5
0
1
2
3
4
MTB
F (D
ays)
Weeks
MTBF
H4 sealing process
155
(d)
(e)
(f)
-1 0 1 2 3 4 5 6 7 8
MTBF 1.75 1.75 1.75 2.33 1.75 2.33 2.33 2.33 2.33 3.5
0
1
2
3
4
MTB
F (D
ays)
Weeks
MTBF
H4 exhausting process
-1 0 1 2 3 4 5 6 7 8
MTBF 0.875 0.875 1 1.116 1 1.75 1.4 1.4 1.75 1.75
0
0.5
1
1.5
2
MTB
F (D
ays)
Weeks
MTBF
Ball bearing face grinding process
-1 0 1 2 3 4 5 6 7 8
MTBF 1.116 1 1.116 1.75 2.333 1.75 2.333 2.333 3.5 3.5
0
1
2
3
4
MTB
F (D
ays)
Weeks
MTBF
Ball bearing OD grinding process
156
(g)
(h)
Fig 5.18 Mean time between failures (MTBF)
(a) H4 forming process (b) H4 jointing process
(c) H4 sealing process (d) H4 exhausting process
(e) Ball bearing face grinding process (f) Ball bearing OD grinding process
(g) Ball bearing inner race grinding line (h) Ball bearing outer race grinding line
-1 0 1 2 3 4 5 6 7 8
MTBF 0.7 0.777 0.777 1 0.875 1 1 1.116 1.4 1.4
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
MTB
F (D
ays)
Weeks
MTBF
Ball bearing IR grinding line
-1 0 1 2 3 4 5 6 7 8
MTBF 0.777 0.636 0.875 1.116 1 1.116 1.4 1.75 1.4 1.75
0
0.5
1
1.5
2
MTB
F (D
ays)
Weeks
MTBF
Ball bearing OR grinding line
157
(a)
(b)
(c)
-1 0 1 2 3 4 5 6 7 8
MTTR 1.5 1.5 1.25 1.25 1.25 1.75 1.25 1.5 1 1
0
0.5
1
1.5
2
MTT
R (
in h
rs.)
Weeks
MTTR
H4 forming process
-1 0 1 2 3 4 5 6 7 8
MTTR 1.5 1.75 1.5 1.25 1.25 1.25 1.25 1 1 1
0
0.5
1
1.5
2
MTT
R (
in h
rs.)
Weeks
MTTR
H4 jointing process
-1 0 1 2 3 4 5 6 7 8
MTTR 1.25 1 1 0.8 1.2 0.75 0.75 0.75 0.75 0.75
0 0.2 0.4 0.6 0.8
1 1.2 1.4
MTT
R (
in h
rs.)
Weeks
MTTR
H4 sealing process
158
(d)
(e)
(f)
-1 0 1 2 3 4 5 6 7 8
MTTR 1.5 1.5 1.25 1 1.25 1 1 1 1 1
0
0.5
1
1.5
2
MTT
R (
in h
rs.)
Weeks
MTTR
H4 exhausting process
-1 0 1 2 3 4 5 6 7 8
MTTR 1.6 1.6 1.35 1.6 1.433 1.1 1.1 1.233 1.1 1
0
0.5
1
1.5
2
MTT
R (
in h
rs.)
Weeks
MTTR
Ball bearing face grinding process
-1 0 1 2 3 4 5 6 7 8
MTTR 1.833 1.6 1.533 1.4 1.25 1.33 1.25 1.25 1.15 1.083
0
0.5
1
1.5
2
MTT
R (
in h
rs.)
Weeks
MTTR
Ball Bearing OD grinding process
159
(g)
(h)
Fig 5.19 Mean time to repair (MTTR)
(a) H4 forming process (b) H4 jointing process
(c) H4 sealing process (d) H4 exhausting process
(e) Ball bearing face grinding process (f) Ball bearing OD grinding process
(g) Ball bearing inner race grinding line (h) Ball bearing outer race grinding line
-1 0 1 2 3 4 5 6 7 8
MTTR 1.5 1.5 1.333 1.25 1.166 1.25 1 1 0.833 0.75
0 0.2 0.4 0.6 0.8
1 1.2 1.4 1.6
MTT
R (
in h
rs.)
Weeks
MTTR
Ball bearing IR grinding line
-1 0 1 2 3 4 5 6 7 8
MTTR 1.5 1.4 1.4 1.333 1.25 1.2 1.166 1 0.75 0.833
0
0.5
1
1.5
2
MTT
R (
in h
rs.)
Weeks
MTTR
Ball bearing OR grinding line
160
(a)
(b)
(c)
-1 0 1 2 3 4 5 6 7 8
A.R. 0.903 0.89 0.911 0.918 0.922 0.924 0.923 0.932 0.939 0.939
0.86
0.88
0.9
0.92
0.94
0.96
Ava
ilab
ility
rat
e
Weeks
Availabilty rate
H4 forming process
-1 0 1 2 3 4 5 6 7 8
A.R. 0.903 0.908 0.916 0.918 0.927 0.924 0.931 0.937 0.936 0.939
0.88 0.89
0.9 0.91 0.92 0.93 0.94 0.95
Ava
ilab
ility
rat
e
Weeks
Availabilty rate
H4 jointing process
-1 0 1 2 3 4 5 6 7 8
A.R. 0.9 0.9 0.916 0.923 0.916 0.936 0.94 0.936 0.942 0.941
0.86
0.88
0.9
0.92
0.94
0.96
Ava
ilab
ility
rat
e
Weeks
Availability rate
H4 sealing process
161
(d)
(e)
(f)
-1 0 1 2 3 4 5 6 7 8
A.R. 0.907 0.908 0.915 0.927 0.915 0.931 0.931 0.932 0.933 0.94
0.89 0.9
0.91 0.92 0.93 0.94 0.95
Ava
ilab
ility
rat
e
Weeks
Availability rate
H4 exhausting process
-1 0 1 2 3 4 5 6 7 8
A.R. 0.673 0.655 0.675 0.689 0.69 0.736 0.729 0.735 0.755 0.763
0.6
0.65
0.7
0.75
0.8
Ava
ilab
ility
rat
e
Weeks
Availability rate
Ball bearing face grinding process
-1 0 1 2 3 4 5 6 7 8
A.R. 0.684 0.691 0.73 0.751 0.752 0.767 0.769 0.765 0.804 0.798
0.6
0.65
0.7
0.75
0.8
0.85
Ava
ilab
ility
rat
e
Weeks
Availability rate
Ball bearing OD grinding process
162
(g)
(h)
Fig 5.20 Availability rate
(a) H4 forming process (b) H4 jointing process
(c) H4 sealing process (d) H4 exhausting process
(e) Ball bearing face grinding process (f) Ball bearing OD grinding process
(g) Ball bearing inner race grinding line (h) Ball bearing outer race grinding line
-1 0 1 2 3 4 5 6 7 8
A.R. 0.91 0.919 0.927 0.947 0.944 0.948 0.957 0.964 0.975 0.977
0.86
0.88
0.9
0.92
0.94
0.96
0.98
1
Ava
ilab
ility
rat
e
Weeks
Availability rate
Ball bearing IR grinding line
-1 0 1 2 3 4 5 6 7 8
A.R. 0.918 0.908 0.933 0.952 0.947 0.957 0.965 0.976 0.977 0.98
0.86
0.88
0.9
0.92
0.94
0.96
0.98
1
Ava
ilab
ility
rat
e
Weeks
Availability rate
Ball bearing OR grinding line
163
(a)
(b)
(c)
-1 0 1 2 3 4 5 6 7 8
P.R. 0.864 0.862 0.889 0.912 0.909 0.924 0.921 0.926 0.925 0.927
0.82
0.84
0.86
0.88
0.9
0.92
0.94
Pe
rfo
rman
ce r
ate
Weeks
Performance rate
H4 forming process
-1 0 1 2 3 4 5 6 7 8
P.R. 0.609 0.611 0.628 0.643 0.658 0.651 0.66 0.665 0.664 0.665
0.58
0.6
0.62
0.64
0.66
0.68
Pe
rfo
rman
ce r
ate
Weeks
Performance rate
H4 jointing process
-1 0 1 2 3 4 5 6 7 8
P.R. 0.576 0.569 0.595 0.62 0.628 0.631 0.629 0.635 0.637 0.636
0.52 0.54 0.56 0.58
0.6 0.62 0.64 0.66
Pe
rfo
rman
ce r
ate
Weeks
Performance rate
H4 sealing process
164
(d)
(e)
(f)
-1 0 1 2 3 4 5 6 7 8
P.R. 0.643 0.64 0.649 0.675 0.698 0.708 0.704 0.706 0.709 0.702
0.6 0.62 0.64 0.66 0.68
0.7 0.72
Pe
rfo
rman
ce r
ate
Weeks
Performance rate
H4 exhausting process
-1 0 1 2 3 4 5 6 7 8
P.R. 0.71 0.709 0.709 0.716 0.734 0.739 0.742 0.74 0.743 0.743
0.69 0.7
0.71 0.72 0.73 0.74 0.75
Pe
rfo
rman
ce r
ate
Weeks
Performance rate
Ball bearing face grinding process
-1 0 1 2 3 4 5 6 7 8
P.R. 0.748 0.748 0.754 0.761 0.765 0.763 0.768 0.773 0.772 0.776
0.73
0.74
0.75
0.76
0.77
0.78
Pe
rfo
rman
ce r
ate
Weeks
Performance rate
Ball bearing OD grinding process
165
(g)
(h)
Fig 5.21 Performance rate
(a) H4 forming process (b) H4 jointing process
(c) H4 sealing process (d) H4 exhausting process
(e) Ball bearing face grinding process (f) Ball bearing OD grinding process
(g) Ball bearing inner race grinding line (h) Ball bearing outer race grinding line
-1 0 1 2 3 4 5 6 7 8
P.R. 0.721 0.718 0.752 0.74 0.765 0.762 0.771 0.778 0.802 0.819
0.66 0.68
0.7 0.72 0.74 0.76 0.78
0.8 0.82 0.84
Pe
rfo
rman
ce r
ate
Weeks
Performance rate
Ball bearing IR grinding line
-1 0 1 2 3 4 5 6 7 8
P.R. 0.727 0.734 0.742 0.758 0.768 0.766 0.774 0.773 0.808 0.809
0.68
0.7
0.72
0.74
0.76
0.78
0.8
0.82
Pe
rfo
rman
ce r
ate
Weeks
Performance rate
Ball bearing OR grinding line
166
(a)
(b)
(c)
-1 0 1 2 3 4 5 6 7 8
Q.R. 0.988 0.988 0.988 0.989 0.99 0.993 0.994 0.994 0.993 0.994
0.984 0.986 0.988
0.99 0.992 0.994 0.996
Qu
alit
y ra
te
Weeks
Quality rate
H4 forming process
-1 0 1 2 3 4 5 6 7 8
Q.R. 0.99 0.99 0.992 0.991 0.992 0.992 0.993 0.992 0.993 0.993
0.988 0.989
0.99 0.991 0.992 0.993 0.994
Qu
alit
y ra
te
Weeks
Quality rate
H4 jointing process
-1 0 1 2 3 4 5 6 7 8
Q.R. 0.985 0.986 0.987 0.988 0.99 0.989 0.991 0.991 0.992 0.993
0.98
0.985
0.99
0.995
Qu
alit
y ra
te
Weeks
Quality rate
H4 sealing process
167
(d)
(e)
(f)
-1 0 1 2 3 4 5 6 7 8
Q.R. 0.984 0.983 0.985 0.987 0.986 0.987 0.989 0.989 0.991 0.991
0.975
0.98
0.985
0.99
0.995
Qu
alit
y ra
te
Weeks
Quality rate
H4 exhausting process
-1 0 1 2 3 4 5 6 7 8
Q.R. 0.9984 0.9985 0.9986 0.9987 0.9987 0.999 0.9991 0.9992 0.9994 0.9994
0.9975
0.998
0.9985
0.999
0.9995
Qu
alit
y ra
te
Weeks
Quality rate
Ball bearing face grinding process
-1 0 1 2 3 4 5 6 7 8
Q.R. 0.9985 0.9984 0.9987 0.9989 0.999 0.9991 0.9991 0.9992 0.9993 0.9993
0.9975
0.998
0.9985
0.999
0.9995
Qu
alit
y ra
te
Weeks
Quality rate
Ball bearing OD grinding process
168
(g)
(h)
Fig 5.22 Quality rate
(a) H4 forming process (b) H4 jointing process
(c) H4 sealing process (d) H4 exhausting process
(e) Ball bearing face grinding process (f) Ball bearing OD grinding process
(g) Ball bearing inner race grinding line (h) Ball bearing outer race grinding line
-1 0 1 2 3 4 5 6 7 8
Q.R. 0.9983 0.9981 0.9984 0.9986 0.9986 0.9989 0.999 0.999 0.9991 0.9992
0.9974 0.9976 0.9978
0.998 0.9982 0.9984 0.9986 0.9988
0.999 0.9992 0.9994
Qu
alit
y ra
te
Weeks
Quality rate
Ball bearing IR grinding line
-1 0 1 2 3 4 5 6 7 8
Q.R. 0.9982 0.9983 0.9985 0.9985 0.9986 0.999 0.9991 0.9991 0.9992 0.9993
0.9976 0.9978
0.998 0.9982 0.9984 0.9986 0.9988
0.999 0.9992 0.9994
Qu
alit
y ra
te
Weeks
Quality rate
Ball bearing OR grinding line
169
(a)
(b)
(c)
-1 0 1 2 3 4 5 6 7 8
OEE 0.77 0.757 0.8 0.828 0.829 0.847 0.844 0.857 0.862 0.865
0.7
0.75
0.8
0.85
0.9
OEE
Weeks
OEE
H4 forming process
-1 0 1 2 3 4 5 6 7 8
OEE 0.544 0.549 0.57 0.584 0.605 0.596 0.61 0.618 0.617 0.62
0.5
0.55
0.6
0.65
OEE
Weeks
OEE
H4 jointing process
-1 0 1 2 3 4 5 6 7 8
OEE 0.51 0.504 0.537 0.565 0.569 0.584 0.585 0.589 0.595 0.594
0.45
0.5
0.55
0.6
0.65
OEE
Weeks
OEE
H4 sealing process
170
(d)
(e)
(f)
-1 0 1 2 3 4 5 6 7 8
OEE 0.573 0.571 0.584 0.617 0.629 0.65 0.648 0.65 0.655 0.653
0.5
0.55
0.6
0.65
0.7
OEE
Weeks
OEE
H4 exhausting process
-1 0 1 2 3 4 5 6 7 8
OEE 0.477 0.463 0.477 0.492 0.505 0.543 0.54 0.543 0.56 0.566
0.4
0.45
0.5
0.55
0.6
OEE
Weeks
OEE
Ball bearing face grinding process
-1 0 1 2 3 4 5 6 7 8
OEE 0.51 0.516 0.549 0.57 0.574 0.584 0.59 0.59 0.62 0.618
0.4
0.45
0.5
0.55
0.6
0.65
OEE
Weeks
OEE
Ball bearing OD grinding process
171
(g)
(h)
Fig 5.23 Overall Equipment effectiveness (OEE)
(a) H4 forming process (b) H4 jointing process
(c) H4 sealing process (d) H4 exhausting process
(e) Ball bearing face grinding process (f) Ball bearing OD grinding process
(g) Ball bearing inner race grinding line (h) Ball bearing outer race grinding line
-1 0 1 2 3 4 5 6 7 8
OEE 0.654 0.658 0.695 0.699 0.721 0.721 0.737 0.749 0.781 0.799
0.6
0.65
0.7
0.75
0.8
0.85
OEE
Weeks
OEE
Ball bearing IR grinding line
-1 0 1 2 3 4 5 6 7 8
OEE 0.666 0.665 0.691 0.72 0.726 0.732 0.746 0.753 0.788 0.792
0.6
0.65
0.7
0.75
0.8
0.85
OEE
Weeks
OEE
Ball bearing OR grinding line
172
(a)
(b)
(c)
-1 0 1 2 3 4
Kaizen 0 2 4 5 6 6
0
2
4
6
8
Kai
zen
Fortnightly
Kaizen
H4 forming process
-1 0 1 2 3 4
Kaizen 1 1 2 6 5 6
0
2
4
6
8
Kai
zen
Fortnightly
Kaizen
H4 jointing process
-1 0 1 2 3 4
Kaizen 2 1 3 5 5 5
0
1
2
3
4
5
6
Kai
zen
Fortnightly
Kaizen
H4 sealing process
173
(d)
(e)
(f)
-1 0 1 2 3 4
Kaizen 1 2 4 4 5 6
0
2
4
6
8
Kai
zen
Fortnightly
Kaizen
H4 exhausting process
-1 0 1 2 3 4
Kaizen 3 4 4 6 5 8
0
2
4
6
8
10
Kai
zen
Fortnightly
Kaizen
BB face grinding process
-1 0 1 2 3 4
Kaizen 6 5 7 9 8 10
0 2 4 6 8
10 12
Kai
zen
Fortnightly
Kaizen
BB outer diameter grinding process
174
(g)
Fig 5.24 Kaizen
(a) H4 forming process (b) H4 jointing process
(c) H4 sealing process (d) H4 exhausting process
(e) Ball bearing face grinding process (f) Ball bearing OD grinding process
(g) Ball bearing inner race / outer race grinding line
-1 0 1 2 3 4
Kaizen 2 4 5 7 7 7
0
2
4
6
8
Kai
zen
Fortnightly
Kaizen
BB IR/OR grinding lines
175
(a)
(b)
(c)
-1 0 1 2 3 4
SHE 6 6 4 5 3 2
0
2
4
6
8
SHE
Fortnight
SHE
H4 forming process
1 2 3 4 5 6
SHE 5 4 3 3 2 2
0 1 2 3 4 5 6
SHE
Fortnight
SHE
H4 jointing process
1 2 3 4 5 6
SHE 6 5 4 4 2 1
0
2
4
6
8
SHE
Fortnight
SHE
H4 sealing process
176
(d)
(e)
(f)
1 2 3 4 5 6
SHE 6 7 5 5 4 2
0
2
4
6
8
SHE
Fortnight
SHE
H4 exhausting process
1 2 3 4 5 6
SHE 4 3 2 1 2 1
0
1
2
3
4
5
SHE
Fortnight
SHE
BB face grinding process
1 2 3 4 5 6
SHE 3 3 2 2 2 1
0
1
2
3
4
SHE
Fortnight
SHE
BB outer diameter grinding process
177
(g)
(h)
Fig 5.25 Safety, health and environment issues
(a) H4 forming process (b) H4 jointing process
(c) H4 sealing process (d) H4 exhausting process
(e) Ball bearing face grinding process (f) Ball bearing OD grinding process
(g) Ball bearing inner race grinding line (h) Ball bearing outer race grinding line
1 2 3 4 5 6
SHE 3 5 2 2 1 1
0
1
2
3
4
5
6
SHE
Fortnight
SHE
BB inner race grinding line
1 2 3 4 5 6
SHE 3 2 2 1 1 1
0
1
2
3
4
SHE
Fortnight
SHE
BB outer race grinding line