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PREFACE
This report is based on the in-plant training of the first six month of National Diploma in
Technology- University of Moratuwa.
My training place was Sri Lanka Railway workshop Ratmalana. They are doing locomotive
repairing and maintenance and manufacture locomotive parts. I was in four electrical workshops.
When I was there I could be able to get vast knowledge. Mainly locomotive and industrial
electrical works. This report gives a brief description of working experience with theoretical things
which I got in my training period.
This report contains four chapters. The organizational structure of the Sri Lanka Railway
Department is described as the introduction in first chapter. Second chapter describes my
experience I had gained during my training period. Then I was added the suggestions I have made
to maximize the efficiency of the workshops and the conclusion which includes a summary of the
training period as the third chapter. Finally the leave record form, training schedule and annex G
are added as in chapter four.
1
ACKNOWLEDGEMENT
My special thank must go to,
All of the academic staff members of Department of Electrical Engineering Technology of
ITUM for afforced with theoretical knowledge in myself and my colleagues.
Mr.R.Perera, Training Engineer of Industrial Training Division of ITUM
Staff of National Apprentice & Industrial Training Authority (NAITA)
Mr.A.D.Wickramasinghe, Training Operation Manager of Sri Lanka German Railway
Technical college and Staff.
All foremen and supervisors of CGR electrical workshops 31 , 35 , 30 , and 39 and
Technicians and rest of the staff helped me to gather deep knowledge and experiences
All of the workshop workers who supported to me for completed my training period
successfully.
My colleagues who had trained with me as electrical and mechanical engineering technology,
for helping me when I was in difficulties and making enjoyable successful training period
W.L.Mahesh
Instutute of Technology
University of Moratuwa.
CONTENTS
2
CHAPTER 01
Introduction …………………………………………………………………..…….………05
CHAPTER 02
AC Motor Rewinding............................................................................................................ 09
Trouble shooting of “Seieere” water pump motor……............................... 12
Cutting grinder machine troubleshooting.............................................................................. 12
Commutator Repair................................................................................................................13
Air conditioner troubleshooting.............................................................................…............14
Air conditioner cleaning ………........................................................................................... 15
Armature balancing………………………………………………………………………....16
Safety and Quality Assurance ……………………………………………………………...17
CHAPTER 3
Suggestions ………………………………………………………………………………... 18
Conclusion …………………………………………………...…………............................. 19
CHAPTER 4
Annex D ................................................................................................................. .. 20
Annex F....................................................................................... ......................21
Annex G.............................................................................................................. 22
INDEX
3
Fig 1: Burned stator winding removing ……………………………………..………………………...
09
Fig 2: cleaned Stator ………………………………………………………………………………….
10
Fig 3: painted stator against corrosion………………………………………………………………..
10
Fig 4: winding former………………………………………………………………………………....
10
Fig 5: removed coils for take details…………………………………………………………………..
10
Fig 6: Stator winding installation …………………………………….................................................
11
Fig 7: Making stator winding connections………………………………………………………….
11
Fig 8: Angle cutting grinder …………………………………………………………………………..
12
Fig 9 : Commutator …………………………………………………………………………………...
13
Fig 10: mica undercutting …………………………………………………………………………….
13
Fig 11: thermostat ………………………………………………………………………………….....
14
Fig 12: : condenser cleaning …………………………………………………………..……….......…
15
Fig 13: rotor at the balancing machine ……………………………………………………...……..…
16
Fig 14: Control panel of armature balancing machine…………………………………………..
……. 16
4
CHAPTER 01
INTRODUCTION
Sri Lanka Railway (SLR) workshop is the sub department (Main Mechanical
Engineering Sub Department) of the Sri Lanka Railway Department under controlled by the
General Manager of Administration (GMA). The highest designation of the SLR workshop is Chief
Mechanical Engineer (CME). The purposes of the railway workshop are well maintaining and
overhauling of the locomotives, carriages & wagons.
CME Sub Department
5
Organizational Structure of Sri Lanka Railway Department
6
CME
DME
MEC MES
FOREMAN
TKC
SUPERVISOR
1ST CLASS TECHNICIAN
2N
D CLASS TECHNICIAN
3RD CLASS TECHNICIAN
LABOURS
TRAINEES
MEF MEP MEU MEL (E)
MEL (H)
MEL (P)
MED
GMR - General Manager of Railway
7
GMR
GMT GMAMain Mechanical Engineering
Sub Department
Main Motive Power Sub Department
Main Way & Works
Engineering Sub
DepartmentSignal & Telecominicati
on Sub Department
Transportation Superintendant
Commercial Superintendant
Chief Accountantof
Railway
Sales Manager
Sri Lanka Railway
Superintendant
Sri Lanka railway force
superintendantSri Lanka German Railway
Technical Training Centre
GMO
GMT - General Manager of Technical
GMA - General Manage of Administrative
GMO - General Manager of Operation
CME - Chief Mechanical Engineer
DME - Deputy Mechanical Engineer
CEE - Chief Electrical Engineer
MEC - Mechanical Engineer of Carriage
MEW - Mechanical Engineer of Wagon
MEF - Mechanical Engineer of Foundry
MEP - Mechanical Engineer of Production
MED - Mechanical Engineer of Drawing
MES - Mechanical Engineer of special project
MEL (E) - Mechanical Engineer of Locomotive (Electrical)
MEL (H) - Mechanical Engineer of Locomotive (Hydraulic)
MEL (P) - Mechanical Engineer of Locomotive (Power)
EEC - Electrical Engineer of Carriage
EET - Electrical Engineer of Traction
EEP - Electrical Engineer of power
TO - Technical Officer
BDF - Building Department Foreman
TKC - time keeper clerk
SK - Store Keeper
RBP - Railing Bus Project
There are both Electrical and Mechanical work shop under controlling Chief mechanical and electrical engineer. But in earlier there was not a chief electrical engineer post. It that period all electrical work shop were maintained and inspected by Ceylon electricity board. Now the administration under took by chief electrical engineer and other there sectional engineers there are,
Electrical engineer carriage. (E.E.C) Electrical engineer traction. (E.E.T) Electrical engineer power. (E.E.P)
8
Also the training students are under trained by the Workshop Forman. The all the workshops are works with together to well maintenance of the locomotives, railroads and the carriages & wagons. According to our training schedule we have four numbers of workshops to our practice.
Workshop 31- AC motors and AC Generators maintains , AC machine rewinding, Ceiling
fan rotor rewinding and Grinder, Grill armature rewinding and maintains , Transformers
rewinding and maintain.
Workshop 35- DC Electrical machines maintained rewinding and repair electronic controls
of Traction motors.
Workshop 30- Battery repairs ,Carriage wiring, Air condition repairs and electroplating
Workshop 39-. Heavy AC and DC Generators, Traction motors, DC traction controls, and
control cubical works, Armature repairs and Armature Balancing.
CHAPTER 2
9
AC Motor Rewinding
We make a rewind for “Khaithan Exhaust Fan” single phase induction motor. Name plate
data of that motor is following.
230V, 2.3A, 500W , 50Hz , 900 rpm
Slots-36
Coil diameter- 600nm
Coil sets- 6
Starting Winding turns- 148, 73 (two coils per one set)
Running Winding turns- 128, 65 (two coils per one set)
Coil pitch- 1/5, 1/7
Winding style- top-top , Bottom-Bottom
First we check windings conductivity using a bulb circuit. W found some burned windings
and decide to remove all windings and make a rewind.
When we remove old windings, we took its data.( no of turns, oil pitch, diameter, and
connection configuration.)
For remove winding easily, we burned stator with coils in oven at 60°C.
Then we cleaned stator core using thinner and knife. Then applied anti-cross paint against
corrosive.
10
Fig 1: Burned stator winding removing
Then we choose a suitable former for rewinding, using taken data. And made windings using winding machine according to details.
11
Fig 2: cleaned Stator Fig 3: painted stator against corrosion
Fig 4: winding former Fig 5: removed coils for take details
then we prepare insulator papers for stator slots. we used combine papers for that. And then inserted coils to slots very carefully. We specially mentioned about coil’s turn side. All coils must be a one side. Also some enough length of coil at end and at start released for connection purposes.
For insert coils, we used special tool made using PVC. It is very useful for insert coil to slots without damages.
When we insert second coil (running winding) to slots, it is very difficult because there was not enough space for that. Therefore we used rubber hammer for tight the coils.
Then made connections according taken data. then insulate joints and cable using sleeves.
Then
12
Fig 6: Stator winding installation
Fig 7: Making stator winding connections
Then applied insulation salac and burned in oven at 90 °C.
After that checked windings again using bulb circuit.
At last, sent it to workshop 35 for reassemble.
Troube shooting of “Seieere” water pump motor
It is single phase 1KW induction motor. The problem is failure to start.
First we checked fuse and circuit breakers. Those are OK.
Then check connections and mega ohm tested.
Then cheked the starting capacitor using another motor. It is not working properly. Then set new 400v, 10µF capacitor . Then the motor is started. But it a noise. We observed bearing temperature is very high. Then we change the bearing and check again.
Cutting grinder machine troubleshooting.
It
It is DEWALT, 20000rpm, 800W angle cutter machine.
13
Fig 8: Angle cutting grinder
First we open the case of machine and carefully removed the brushes from the brushine holder.those were wear. Replace new brushes, because those were not matched with machine. Then we made those brushes shape using Amery paper according to old ones.
Then assemble it by feeding the wire to the pin and twist .then placed the brushes.
Commutator Repair:
In DC machines, when replacing brushes, we checked commutator for wear and damages. If commutator is worn down more than 1/32 inch on the diameter or is pitted, we have to turning it and after undercutting also.
First we mounted the armature on lathe machine and align the armature. We used diamond tool as a cutting tool. Then Turning and facing the commutator carefully using automatic cutter running mode.
The following tolerances can be achieved:
Bar to bar deviation = .0001” (.00254mm)
T.I.R. = .0003” (.00762mm)
Surface finish:
Single cut = 32 micro inch (0.8 micro meter)
Double cut = 16 micro inch (0.4 micro meter)
14
Fig 9: Commutator
Now, no clearance between two commutates parts because of the turning. Therefore we
made its clearance using steel blade. That is the mica undercutting. After undercutting, we
polish the commutator using very thick emery paper.
Air conditioner troubleshooting
It is LG 11,500 BTU Air Conditioner at a office.
First we checked the thermostat was set to “cool” and that the set temperature was well
below the ambient temperature. Then we checked the main electrical panel and other
secondary circuit panel for a tripped breaker or blown fuse, but not found. Then we
checked the furnace power switch was turned on and that the outdoor condenser’s power
switch, which is mounted on the outdoor unit, hasn’t been shut off. Also checked the 240-
volt disconnect next to the compressor, which is in a metal box usually mounted on the
house wall, hasn’t been shut off.
15
Fig 10: mica undercutting
So then remove the cover and checked the thermostat. Removed the thermostat’s cover
and unscrew the wire from the terminal. then turn the power back on. Holded the wire by
its insulation only, touched the bare end to the another terminal and hold it there for about
two minutes. The compressor is kicked on. It means the thermostat is faulty. then we
replace it and checked again. The problem was fixed. But not cooling.
Air conditioner cleaning
A central air conditioner that runs but doesn’t cool may just need to be cleaned.
First we raked leaves and debris away from the outdoor condenser. Then trim bushes that
might block airflow.
16
Fig 11: thermostat
Fig 12: condenser cleaning
Then unscrew and removed protective grilles and the top cover from the compressor. The
fan is attached to the grille, therefore we carefully for not to pull any wires loose.
Then used a soft brush to clean dirt and debris from the fins, and then vacuum the fins with
a brush attachment.
From inside the unit, we used a hose and nozzle with a trigger grip to spray debris from
the fins (protect the wiring and motor with plastic sheeting or a large plastic garbage bag).
Then reassembled the parts and powered. It started works properly.
Armature Balancing
In work shop 39 they used Dynamic Balancing Method for armature balancing. When the motor
vibrate due to unbalanced armature, armature balance is essential. The procedure of dynamic
balancing using fully automatic machine is following.
• Place rotor on to the bearing of the machine.
• Then Close counter Support
• Set belt around the rotor for running.
• Set electronic metering units in accordance with rotor dimensions, balancing
speed.
• Set , black point indicator with white paper to the rotor.
17
Fig 13: rotor at the balancing machine
• Set the sensor and degree scale around rotor.
• Switch on driving motor.
• Start drive and run the rotor, up to balancing speed.
• Take and retain the reading.
It gives wanted weights at suitable degree points according to degree scale. Then we measure
resulted weights (iron pieces) using electronic balance and fix those at given points.
Safety:
CGR has very wide fire protection system. It has all instruments and vehicles for the fire.
But all workshops haven’t good rain water proof method. In April, May this year all workshops fill
in rain water and large no of Instruments and machines destroy because of the water.
Workers do not use safety helmets and boots, grouses etc... Large Cranes with many tons of
weights always go on workers heads.
Worker have no good safety methods for working with electrical goods.
Quality Assurance
All workshops use 5S methods. But in practically it is not very successful.
Because have to handle very heavy and large Items, engines and some workshops have no much
space and also some workshops are so busy. And main thing is workers have no idea about quality
assurance.
18
Fig 14 : Control panel of armature balancing machine
CHAPTER 3
SUGGESTIONS
• Make practically success regulations and rules.
• Built good Quality assurance system
• Stop political placements
• Use new technologies.
• Make good communication system
Stop the political coercion and the appointments in the workshop.
Take employers and giving promotions for them according to the organization rules. Also
give opportunity to young person with better experience for join the higher designations in
Sri Lanka Railway Department.
19
Organize new technologies workshops for Formans and Technicians..
Give the instructions about the employee’s safety and advice them to follow the safety
instructions. Also introduce the new technology.
Make good travelling system within the workshop
Remove all unnecessary parts and carriages from workshop area.
Additionally that, I would like to request about the following things as the training student.
Make our schedules with good balance with both production and automobile sections.
Give us opportunity to borrow the manuals of the machines, locomotives and their
components, from the technical library.
CONCLUSION
As a student we can ask any question from workshop foreman and even from workers. No
one try to neglect us. But if we ask question after that, it may cause to lower the quality of our
profession. After my first industrial training I can improve my knowledge about the production
field.
We have technical background. We learnt lot of theories in the institute and didn’t see the
application of those. But during first industrial training period we saw how it can be used our
theoretical knowledge for practical applications.
The seminar held by the NAITA prior to the training and held in Campus by training engineer was
valuable things.
All of the workers in the workshops were really helpful to me by guiding to get working experience
and educating me to get knowledge about some are new for me. Also the resources that were
available to me were very satisfactory.
20
In my training session I not only gained the technical knowledge and also got the knowledge about
how to dealing with working environment, how to dealing with the officers & the workers, how to
maintaining the stocks in the workshops and their importance.
Finally, I think my first training period is I finished very successfully and I am very satisfactory.
CHAPTER 04
Annex D
LEAVE RECORD FORM
To be sent by registered post to Head of Industrial Training, Institute of Technology, University of Moratuwa after completing each six month period.
1. Name of Trainee: W.L.Mahesh
2. Industrial Training: 1 st six months
(1st six months / 2nd six months)
3. Training Establishment: Sri Lanka Railway Workshop, Ratmalana
4. Leave Record
1st Month 2nd Month 3rd Month 4th Month 5th Month 6th Month
21
No. of days on Leave
- 2 1 2 1
5. Has the leave been approved by the Establishment: Yes
Date:
Signature of Trainee
Note: This is mainly for the information of ITUM and not to replace the standard leave application form, which has to be forwarded to the organization.
Annex G
CONFIDENTIAL
NATIONAL APPRENTICE AND INDUSTRIAL TRAINING AUTHORITY 1 ST SIX MONTHS / 2 ND
SIX MONTHS ASSESSMENT OF N.D.T. APPRENTICE 2010
Place of Assessment: …………………………………. Date of Assessment: ………………...... …………………………………. Time: ………………….
Field: ………………………………………………………
Serial
No.Name
Assessment element
Remarks
Da
ily D
iary
Pro
gre
ss
rep
ort
s (2
x5)
Fin
al r
epo
rt
Tec
hn
ica
l Kn
ow
led
ge
Att
end
ance
, Co
nd
uct
&H
um
an
Rel
ati
on
s
Ind
ust
rial
& L
ab
ou
rL
aws
TO
TA
L
P
AS
S /
FA
IL
15 10 20 40 10 05 100
1.
2.
3.
22
4.
5.
6.
7.
8.
9.
10.
11.
12.
NAME OF EXAMINER DESIGNATION SIGNATURE
1.
2.
3.
4.
5.
23