Workshop Practical Manual

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MCB1043: Manufacturing Technology

Workshop Practical Manual May, 2011 Semester

Student Name: Student ID:

Date Actual Group

Number

Attendance (Technician’s

Stamp)

Lab Manual Marks

Work Piece Marks

Conventional Milling Conventional Lathe CNC Milling 1 CNC Milling 2 CNC Lathe 1 CNC Lathe 2 CNC Bridgeport Arc Welding 1 Arc Welding 2 Arc Welding 3 Metrology

Note: All lab reports must be completed by the end of each lab session. Late submissions will not be accepted.

Receive By: Date/Time: _____________

2

SAFETY AGREEMENT

I, named as below, fully understand all the regulations pertaining to the Health, Safety and Environment in the laboratory as listed in Appendix J of this manual, and therefore shall abide and follow all the rules and instructions. Name: IC/Passport No: Date: Signature:

3

1. Conventional Milling

1.1 Objective: To perform milling processes on a rectangular workpiece according to specifications given in a technical drawing. 1.2 Workshop Outcomes

At the end of this workshop, students should be able to: 1. Explain the components of conventional milling machines. 2. Generate a milling process plan based on an end product. 3. Use a milling machine in the appropriate manner and according to

relevant safety standards. 1.3 Machine Specifications

Distance between spindle axis and table working surface: 30mm – 440mm

Distance between body vertical guides and table body: 218mm – 469mm

Table working surface: 300 mm x 1250 mm Table swivel: 45o Feed: Normal – longitudinal 12.5 – 630 mm/min Transversal 12.5 – 630 mm/min Vertical 5.2 – 262 mm/min Main drive: 40 – 2000 RPM Main drive motor: 5.5 kW, 1440 RPM Feed drive motor: 1.5 kW, 920 RPM

1.4 Refer to Appendix A for procedures and machine operation details. For full operations manual, consult lab technicians and equipment manual. 1.5 Safety Instructions:

Never operate the machine without wearing the correct protective clothing, (i.e. safety shoes, safety glasses, overalls – do not wear loose clothing, do not wear jewellry).

Make sure the machine is suitably positioned and that the surrounding floor area is kept clean and free from scrap material, oil and grease.

Always concentrate on your work – careless acts can result in serious injury.

Persons not involved in machine operation should be kept at a safe distance.

Do not engage in the machine’s main drive with a loose workpiece or cutting tool.

Do not attempt to adjust or remove tools when the machine is in operation.

Always use protective screen when working with the vertical milling head

Ensure that the cutting tools are suitable and in good working order.

4

Technical Drawing (label the figure)

5

1.6 Project Report: Conventional Milling

A. Sketch the conventional milling machine, label the major components and state the functions of these components.

No Component Function

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

6

B. Sketch the tooling and workholding devices to be used and state the functions of these components.

7

C. Summarize the process plan for machining the part.

Operation Sheet Part Name: Op no. Operation Machine

tool Cutting

tool Cutting Speed

Spindle Speed (RPM)

Feed DOC Remarks

1.

2.

3.

4.

5.

6.

7.

8.

9.

10

Date:

8

D. Results

Dimensional check

Dimension Nominal Actual Technician’s

Verification A

B

C

D

E

9

E. Discussion

F. Conclusion

10

MCB1043: Manufacturing Technology

Workshop Practical Manual May, 2011 Semester

Student Name: Student ID:

Date Actual Group

Number

Attendance (Technician’s

Stamp)

Lab Manual Marks

Work Piece Marks

Conventional Milling Conventional Lathe CNC Milling 1 CNC Milling 2 CNC Lathe 1 CNC Lathe 2 CNC Bridgeport Arc Welding 1 Arc Welding 2 Arc Welding 3 Metrology

Note: All lab reports must be completed by the end of each lab session. Late submissions will not be accepted.

Receive By: Date/Time: _____________

11

SAFETY AGREEMENT

I, named as below, fully understand all the regulations pertaining to the Health, Safety and Environment in the laboratory as listed in Appendix J of this manual, and therefore shall abide and follow all the rules and instructions. Name: IC/Passport No: Date: Signature:

12

2. Conventional Lathe

2.1 Objective: To perform lathe processes on a cylindrical workpiece according to specifications given in a technical drawing. 2.2 Workshop Outcomes

At the end of this workshop, students should be able to: 1. Explain the components of a conventional lathe engine. 2. Generate a lathe process plan based on an end product. 3. Use a lathe engine in the appropriate manner and according to

relevant safety standards. 2.3 Machine Specifications 2.4 Refer to Appendix B for procedures and machine operation details. For full operations manual, consult lab technicians and equipment manual. 2.5 Safety Instructions

Ensure quill cover, rapid traverse mechanism and control panel and chuck guard are closed

DO NOT operate machine if there are any faults in the electrical cabinet door, quill cover or chuck guard interlocks

Isolate power in advance for maintenance and repairs. The machine should be stopped at the slightest fault, the cause

established and rectified. Only then should the machine be restarted

DO NOT operate machine if the clearance between the guideways and the sliding surfaces of the carriage exceeds 0.03 mm.

DO NOT operate the machine when the tool is not correctly fixed, when hard allowed plates with improper welding are used, or when the hard allowed replacement plates are incorrectly fixed.

Ensure that you have selected a suitable mode of operation and cutting tool.

Tighten the loosened tailstock if necessary. Ensure that you know how to stop a machine before starting it. Keep all guards, covers and doors in place and closed. Never lay anything on the working surface of the machine. Stop the machine immediately should anything unexpected happen.

13

Technical Drawing (label the figure)

14

2.6 Project Report: Conventional Lathe

A. Sketch the conventional milling machine, label the major components and state the functions of these components.

No. Component Function

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

15

B. Sketch the tooling and workholding devices to be used and state the functions of these components.

16

C. Summarize the process plan for machining the part.

Operation Sheet Part Name: Op no. Operation Machine

tool Cutting

tool Cutting Speed

Spindle Speed (RPM)

Feed DOC Remarks

1.

2.

3.

4.

5.

6.

7.

8.

9.

10

Date:

17

D. Results

Dimensional check

Dimension Nominal Actual Technician’s

Verification A

B

C

D

E

18

E. Discussion

F. Conclusion

19

MCB1043: Manufacturing Technology

Workshop Practical Manual May, 2011 Semester

Student Name: Student ID:

Date Actual Group

Number

Attendance (Technician’s

Stamp)

Lab Manual Marks

Work Piece Marks

Conventional Milling Conventional Lathe CNC Milling 1 CNC Milling 2 CNC Lathe 1 CNC Lathe 2 CNC Bridgeport Arc Welding 1 Arc Welding 2 Arc Welding 3 Metrology

Note: All lab reports must be completed by the end of each lab session. Late submissions will not be accepted.

Receive By: Date/Time: _____________

20

SAFETY AGREEMENT

I, named as below, fully understand all the regulations pertaining to the Health, Safety and Environment in the laboratory as listed in Appendix J of this manual, and therefore shall abide and follow all the rules and instructions. Name: IC/Passport No: Date: Signature:

21

3. CNC Milling 1

3.1 Objective: To perform CNC programming and operation of a CNC milling machine. 3.2 Workshop Outcomes

At the end of this workshop, students should be able to: 1. Explain the components of a CNC milling machine. 2. Generate a part programme. 3. Use a CNC Milling Machine in the appropriate manner and

according to relevant safety standards. 3.3 Machine Specifications:

Maximum cross travel 90mm Maximum longitudinal travel 170mm Maximum head travel 115mm Working table surface 360mm x 130mm Spindle speed 0 – 4000 RPM Machine resolution 0.01mm

3.4 Refer to Appendix C for procedures and machine operation details. For full operations manual, consult lab technicians and equipment manual. 3.5 Safety Instructions

All activities in the CNC lab must be done under supervision. Familiarize yourself with the procedure before actually

operating the equipment. If unsure, request assistance from the lab instructor.

Immediately report all malfunctions or unusual occurrences to the lab instructor.

Wear suitable clothing. No open-toe shoes are allowed. Slippers, bracelet, wristwatches and rings are strictly prohibited during lab.

Ensure that workpiece is secured before operating the machine.

Follow safety instructions by the lab instructor. Apron must be worn at all time during each practice session. Avoid foolish behaviour and concentrate on your practice. Only operate machine when the safety guards are closed. Never touch any moving parts of the machine or workpiece. Ensure that there are no loose items near the machine.

22

3.6 Tasks

1. Determine the appropriate machining parameters as in 3.7.B 2. Perform all start-up and initialization procedures 3. Set the origin at the top center of the workpiece 4. Perform a linear interpolation along x-axis 5. Performa a linear interpolation along y-axis 6. Perform a linear interpolation along both x and y axes 7. Perform a circular clockwise interpolation with an arc radius of 15 mm and arc start at 10,10. 8. Perform a circular counter-clockwise interpolation with an arc radius of 1.5 inches and arc start at -10,-10. 9. Create a square profile with a 45 mm width, using right hand radius compensation

3.7 Project Report: CNC Milling 1

A. Sketch the CNC milling machine, label the major components and state the functions of these components.

23

B. Machining parameters Determine the appropriate (range of) machining parameters:

Cutting Speed: Feed: Depth of cut: Spindle speed:

24

C. Part programme

i) Header

Part Program - Header ii) Part programme (body) for 3.6.3

Part Program - Body

iii) Part programme (body) for 3.6.4

Part Program - Body

iv) Part programme (body) for 3.6.5

Part Program - Body

25

v) Part programme (body) for 3.6.6

Part Program - Body

vi) Part programme (body) for 3.6.7

Part Program - Body

vii) Part programme (body) for 3.6.8

Part Program - Body

viii) Part programme (body) for 3.6.9

Part Program - Body

26

D. Results

E. Discussion

F. Conclusion

27

4. CNC Milling 2

4.1 Objective: To perform CNC programming and machining on a rectangular workpiece according to the given pattern and dimensions. 4.2 Workshop Outcomes

At the end of this workshop, students should be able to: 1. Generate a milling process plan based on an end product. 2. Use a CNC milling machine in the appropriate manner and

according to relevant safety standards. 4.3 Machine Specifications:

Maximum cross travel 90mm Maximum longitudinal travel 170mm Maximum head travel 115mm Working table surface 360mm x 130mm Spindle speed 0 – 4000 RPM Machine resolution 0.01mm

4.4 Refer to Appendix C for procedures and machine operation details. For full operations manual, consult lab technicians and equipment manual. 4.5 Safety Instructions

All activities in the CNC lab must be done under supervision. Familiarize yourself with the procedure before actually

operating the equipment. If unsure, request assistance from the lab instructor.

Immediately report all malfunctions or unusual occurrences to the lab instructor.

Wear suitable clothing. No open-toe shoes are allowed. Slippers, bracelet, wristwatches and rings are strictly prohibited during lab.

Ensure that workpiece is secured before operating the machine.

Follow safety instructions by the lab instructor. Apron must be worn at all time during each practice session. Avoid foolish behaviour and concentrate on your practice. Only operate machine when the safety guards are closed. Never touch any moving parts of the machine or workpiece. Ensure that there are no loose items near the machine.

28

4.6 Project Report: CNC Milling 2

A. Pattern and dimensions for tool path

29

B. Machining parameters Determine the appropriate (range of) machining parameters:

Cutting Speed: Feed: Depth of cut: Spindle speed:

30

C. Summarize the process plan for machining the part.

Operation Sheet

Part Name:

Op no Operation Machine

tool Cutting

tool Cutting Speed

Spindle Speed (RPM)

Feed DOC Remarks

1.

2.

3.

4.

5.

6.

7.

8.

9.

Date:

31

D. Part program.

Part Program

E. Results

32

F. Discussion

G. Conclusion

33

MCB1043: Manufacturing Technology

Workshop Practical Manual May, 2011 Semester

Student Name: Student ID:

Date Actual Group

Number

Attendance (Technician’s

Stamp)

Lab Manual Marks

Work Piece Marks

Conventional Milling Conventional Lathe CNC Milling 1 CNC Milling 2 CNC Lathe 1 CNC Lathe 2 CNC Bridgeport Arc Welding 1 Arc Welding 2 Arc Welding 3 Metrology

Note: All lab reports must be completed by the end of each lab session. Late submissions will not be accepted.

Receive By: Date/Time: _____________

34

SAFETY AGREEMENT

I, named as below, fully understand all the regulations pertaining to the Health, Safety and Environment in the laboratory as listed in Appendix J of this manual, and therefore shall abide and follow all the rules and instructions. Name: IC/Passport No: Date: Signature:

35

5. CNC Lathe 1

5.1 Objective: To perform CNC programming and operation of a CNC lathe machine. 5.2 Workshop Outcomes

At the end of this workshop, students should be able to: 1. Explain the components ofa CNC lathe machine. 2. Generate a part programme. 3. Use a CNC lathe machine in the appropriate manner and according to

relevant safety standards. 5.3 Machine Specifications

Swing over bed 150mm Swing over cross slide 50mm Distance between centers 300mm Spindle power 1 HP Spindle speed 0-3000 RPM Machine resolution 0.01 mm

5.4 Refer to Appendix D for procedures and machine operation details. For full operations manual, consult lab technicians and equipment manual. 5.5 Safety Instructions

1. All activities in the CNC lab must be done under supervision. 1. Familiarize yourself with the procedure before actually

operating the equipment. If unsure, request assistance from the lab instructor.

2. Immedeately report all malfunctions or unusual occurences to the lab instructor.

3. Wear suitable clothing. No open-toe shoes are allowed. Slippers, bracelet, wristwatches and rings are strictly prohibited during lab.

4. Ensure that workpiece is secured before operating the machine.

5. Follow safety instructions by the lab instructor. 6. Apron must be worn at all time during each practice session. 7. Avoid foolish behaviour and concentrate on your practice. 8. Only operate machine when the safety guards are closed. 9. Never touch any moving parts of the machine or workpiece. Ensure that there are no loose items near the machine.

36

5.6 Tasks

1. Determine the machining parameters as in 6.7.B 2. Perform all start-up and initialization procedures 3. Use rapid traverse to move the cutting tool close (within 3 mm) to the workpiece 4. Use G01 to reduce 1mm of the work piece diameter 5. Use G01 to face 1mm off the work piece

6. Perform taper process using G01 code from datum point (0,0) to (X10, Z-10).Use simulation mode to view the process. 7. Use simulation process to view G02 machining profile from datum point (0,0) to point (X10, Z-10). 8. Use G03 code to produce circular interpolation machining profile from datum point (0,0) to point (X10, Z-10)

5.7 Project Report: CNC Lathe

A. Sketch the CNC lathe machine, label the major components and state the functions of these components.

37

B. Machining parameters Determine the appropriate (range of) machining parameters:

Cutting speed: Feed: Depth of cut: Initial spindle speed:

C. Part programme

i) Header

Part Program - Header

38

ii) Part programme (body) for 6.6.3

Part Program - Body

iii) Part programme (body) for 6.6.4 Part Program - Body

iv) Part programme (body) for 6.6.5

Part Program - Body

v) Part programme (body) for 6.6.6

Part Program - Body

39

vi) Part programme (body) for 6.6.7 Part Program - Body

viii) Part programme (body) for 6.6.8

Part Program - Body

vii) Part programme (end)

Part Program - End

40

D. Results

G. Discussion

H. Conclusion

41

6. CNC Lathe 2

6.1 Objective: To perform CNC programming and machining on a cylindrical workpiece according to the given pattern and dimensions. 6.2 Workshop Outcomes

At the end of this workshop, students should be able to: 1. Generate a lathe process plan based on an end product. 2. Use a CNC lathe machine in the appropriate manner and according

to relevant safety standards. 6.3 Machine Specifications:

Swing over bed 150mm Swing over cross slide 50mm Distance between centers 300mm Spindle power 1 HP Spindle speed 0-3000 RPM Machine resolution 0.01 mm

6.4 Refer to Appendix D for procedures and machine operation details. For full operations manual, consult lab technicians and equipment manual. 6.5 Safety Instructions

All activities in the CNC lab must be done under supervision. Familiarize yourself with the procedure before actually

operating the equipment. If unsure, request assistance from the lab instructor.

Immedeately report all malfunctions or unusual occurences to the lab instructor.

Wear suitable clothing. No open-toe shoes are allowed. Slippers, bracelet, wristwatches and rings are strictly prohibited during lab.

Ensure that workpiece is secured before operating the machine.

Follow safety instructions by the lab instructor. Apron must be worn at all time during each practice session. Avoid foolish behaviour and concentrate on your practice. Only operate machine when the safety guards are closed. Never touch any moving parts of the machine or workpiece. Ensure that there are no loose items near the machine.

42

6.6 Project Report: CNC Lathe 2

A. Pattern and dimensions for tool path

43

B. Machining parameters Determine the appropriate (range of) machining parameters:

Cutting Speed: Feed: Depth of cut: Spindle speed:

44

C. Summarize the process plan for machining the part.

Operation Sheet Part Name:

Op no Operation Machine

tool Cutting

tool Cutting Speed

Spindle Speed (RPM)

Feed DOC Remarks

1.

2.

3.

4.

5.

6.

7.

8.

9.

Date:

45

D. Part program.

Part Program

E. Results

46

F. Discussion

G. Conclusion

47

MCB1043: Manufacturing Technology

Workshop Practical Manual May, 2011 Semester

Student Name: Student ID:

Date Actual Group

Number

Attendance (Technician’s

Stamp)

Lab Manual Marks

Work Piece Marks

Conventional Milling Conventional Lathe CNC Milling 1 CNC Milling 2 CNC Lathe 1 CNC Lathe 2 CNC Bridgeport Arc Welding 1 Arc Welding 2 Arc Welding 3 Metrology

Note: All lab reports must be completed by the end of each lab session. Late submissions will not be accepted.

Receive By: Date/Time: _____________

48

SAFETY AGREEMENT

I, named as below, fully understand all the regulations pertaining to the Health, Safety and Environment in the laboratory as listed in Appendix J of this manual, and therefore shall abide and follow all the rules and instructions. Name: IC/Passport No: Date: Signature:

49

7. CNC Bridgeport Milling

7.1 Objective: To perform CNC program and machining on a rectangular work piece according to the given technical drawing. 7.2 Workshop Outcomes

At the end of this workshop, students should be able to: 4. Generate a milling process plan & part program based on an end

product. 5. Use a CNC Bridgeport milling machine in the appropriate manner

and according to relevant safety standards. 7.3 Machine Specifications:

Manufacturer Bridgeport Model VMC 2216 Maximum travel X Axis 560 mm Y Axis 406 mm Z Axis 508 mm Working table surface 838mm x 356mm Table load 341 kg Spindle speed 0 – 10,000 RPM

7.4 Refer to Appendix K for procedures and machine operation details. For full operations manual, consult lab technologists and equipment manual. 7.5 Safety Instructions

All activities in the CNC lab must be done under supervision. Familiarize yourself with the procedure before actually

operating the equipment. If unsure, request assistance from the lab instructor.

Immediately report all malfunctions or unusual occurrences to the lab instructor.

Wear suitable clothing. No open-toe shoes are allowed. Slippers, bracelet, wristwatches and rings are strictly prohibited during lab.

Ensure that work piece is secured before operating the machine.

Follow safety instructions by the lab instructor. Apron must be worn at all time during each practice session. Avoid foolish behavior and concentrate on your practice. Only operate machine when the safety guards are closed. Never touch any moving parts of the machine or work piece. Ensure that there are no loose items near the machine.

50

7.6 Tasks

1. Generate a milling process plan and part program based on the given technical drawing.

2. Use a CNC Bridgeport milling machine to perform the machining process.

7.7 Project Report: CNC Bridgeport Milling

A. Part Program

Part Program

51

B. Results

C. Discussion

D. Conclusion

52

8. CNC Bridgeport Lathe

8.1 Objective: To perform CNC program and machining on a cylindrical work piece according to the given technical drawing. 8.2 Workshop Outcomes

At the end of this workshop, students should be able to: 1. Generate a lathe process plan & part program based on an end

product. 2. Use a CNC Bridgeport lathe machine in the appropriate manner and

according to relevant safety standards.

8.3 Machine Specifications

Manufacturer Bridgeport Romi Model Power Path - 15 Power 25 KVA Voltage 230 VAC Current 63 A Cutting Diameter 280 mm Cutting Length 540 mm Bore 51 mm Tool 12 piece Spindle 0 - 4500 rpm Chuck size 203 mm

8.4 Safety Instructions

1. All activities in the CNC lab must be done under supervision. 2. Familiarize yourself with the procedure before actually

operating the equipment. If unsure, request assistance from the lab instructor.

3. Immediately report all malfunctions or unusual occurrences to the lab instructor.

4. Wear suitable clothing. No open-toe shoes are allowed. Slippers, bracelet, wristwatches and rings are strictly prohibited during lab.

5. Ensure that work piece is secured before operating the machine.

6. Follow safety instructions by the lab instructor. 7. Apron must be worn at all time during each practice session. 8. Avoid foolish behavior and concentrate on your practice. 9. Only operate machine when the safety guards are closed. 10. Never touch any moving parts of the machine or work piece. Ensure that there are no loose items near the machine.

53

8.5 Tasks 1. Generate a lathe process plan and part program based on the given

technical drawing. 2. Use a CNC Bridgeport lathe machine to perform the machining

process.

8.6 Project Report: CNC Bridgeport Lathe

H. Part Program

Part Program

54

I. Results

J. Discussion

K. Conclusion

55

MCB1043: Manufacturing Technology

Workshop Practical Manual May, 2011 Semester

Student Name: Student ID:

Date Actual Group

Number

Attendance (Technician’s

Stamp)

Lab Manual Marks

Work Piece Marks

Conventional Milling Conventional Lathe CNC Milling 1 CNC Milling 2 CNC Lathe 1 CNC Lathe 2 CNC Bridgeport Arc Welding 1 Arc Welding 2 Arc Welding 3 Metrology

Note: All lab reports must be completed by the end of each lab session. Late submissions will not be accepted.

Receive By: Date/Time: _____________

56

SAFETY AGREEMENT

I, named as below, fully understand all the regulations pertaining to the Health, Safety and Environment in the laboratory as listed in Appendix J of this manual, and therefore shall abide and follow all the rules and instructions. Name: IC/Passport No: Date: Signature:

57

9. Welding 1

9.1 Objective: Familiarization with welding operations 9.2 Machine specifications

Nichia Arc Welding Machine, ND-300 Stick electrode welding Input voltage: 220 V, Frequency:50/60 Hz, Rated input: 13 kW

Output no-load voltage: 80 V Output range: AC 50 – 300 A, DC 30 – 250 A

9.3 Refer to Appendix E for procedures and operation details. For complete operations manual, consult lab technicians and equipment manual. 9.4 Safety Instructions:

Keep at a safe distance from the demonstrator. Exercise caution as welding fumes may be harmful to the welder. Ensure you utilize the available personal protective equipment (i.e.

welding helmet/goggles, chipping goggles, leather gloves, electrode holder, welding jacket).

Wear closed toe shoes, preferably boots. Discard frayed cords and wires Keep working area clean.

58

9.5 Tasks 1. Familiarize yourself with the welding equipment, workpiece and

welding parameters. 2. Check and modify the straightness and the squareness of the

surface.

3. Place the workpiece on the table in a flat position. Using the face

shield, mark/touch the electrode to the workpiece to produce an arc.

4. Move the electrode slowly while pressing the electrode until it

reaches the end of the workpiece. When reaching the end of the workpiece, raise the electrode and turn it away from the workpiece.

5. With your safety goggles on, remove the slag and examine the

weld by chipping with a hammer or wire brush. (USE EXTREME CARE AS THE METAL WILL BE HOT)

59

6. Examine your workpiece. Consult the workshop instructor on how to improve your weld.

GOOD POOR POOR 7. Continue practicing bead forming until you obtain a satisfactory result. 9.6 Project Report A A. Welding equipment, workpiece and welding parameters

Title: 1.

2.

3.

60

4.

5.

9.7 Project Report B A. Welding equipment, workpiece and welding parameters

Title: 1.

2.

3.

4.

5.

61

B. Discussion

C. Conclusion

62

10. Welding 2

10.1 Objective: Performing a butt joing and lap weld 10.2 Machine specifications

Nichia Arc Welding Machine, ND-300 Stick electrode welding Input voltage: 220 V, Frequency:50/60 Hz, Rated input: 13 kW

Output no-load voltage: 80 V Output range: AC 50 – 300 A, DC 30 – 250 A

10.3 Refer to Appendix E for procedures and operation details. For complete operations manual, consult lab technicians and equipment manual. 10.4 Safety Instructions: 10.5.A Butt joint 1. Check and ensure that the workpieces are straight and flat.

2. Tack weld the workpieces into a butt joint.

3. Use a face shield, mark/touch the electrode to produce an arc.

When there is a spark, ensure that the angle and distance are

Keep at a safe distance from the demonstrator. Exercise caution as welding fumes may be harmful to the welder. Ensure you utilize the available personal protective equipment (i.e.

welding helmet/goggles, chipping goggles, leather gloves, electrode holder, welding jacket).

Wear closed toe shoes, preferably boots. Discard frayed cords and wires Keep working area clean.

63

correct for welding the workpiece. Move the electrode slowly while pressing the electrode until it reaches the end of the workpiece. When reaching the end of the workpiece, raise the electrode and turn it away from the workpiece

4. With your safety goggles on, remove the slag and examine the weld by chipping with a hammer or wire brush. (USE EXTREME CARE AS THE METAL WILL BE HOT)

5. Examine your workpiece. Consult the workshop instructor on how to improve your weld.

GOOD POOR POOR

64

11.5.B Lap weld

1. Check and ensure that the workpieces are straight and flat. 2. Tack weld the workpieces into a lap joint.

3. Use a face shield, mark/touch the electrode to produce an arc. When there is a spark, ensure that the angle and distance are correct for welding the workpiece. Move the electrode slowly while pressing the electrode until it reaches the end of the workpiece. When reaching the end of the workpiece, raise the electrode and turn it away from the workpiece

4. With your safety goggles on, remove the slag and examine the weld by chipping with a hammer or wire brush. (USE EXTREME CARE AS THE METAL WILL BE HOT)

65

5. Examine your workpiece. Consult the workshop instructor on how to improve your weld.

GOOD POOR POOR 10.6 Project Report

A. Results

B. Discussion

66

C. Conclusion

67

11. Welding 3

11.1 Objective: Performing a T-joint and corner joint 11.2 Machine specifications

Nichia Arc Welding Machine, ND-300 Stick electrode welding Input voltage: 220 V, Frequency:50/60 Hz, Rated input: 13 kW

Output no-load voltage: 80 V Output range: AC 50 – 300 A, DC 30 – 250 A

11.3 Refer to Appendix E for procedures and operation details. For complete operations manual, consult lab technicians and equipment manual. 11.4 Safety Instructions:

Keep at a safe distance from the demonstrator. Exercise caution as welding fumes may be harmful to the welder. Ensure you utilize the available personal protective equipment (i.e.

welding helmet/goggles, chipping goggles, leather gloves, electrode holder, welding jacket).

Wear closed toe shoes, preferably boots. Discard frayed cords and wires Keep working area clean.

68

11.5.A T-Joint 1. Check and ensure that the workpieces are straight and flat.

2. Tack weld the workpieces into a T-shaped joint.

3. Use a face shield, mark/touch the electrode to produce an arc. When there is a spark, ensure that the angle and distance are correct for welding the workpiece. Move the electrode slowly while pressing the electrode until it reaches the end of the workpiece. When reaching the end of the workpiece, raise the electrode and turn it away from the workpiece

69

4. With your safety goggles on, remove the slag and examine the weld by chipping with a hammer or wire brush. (USE EXTREME CARE AS THE METAL WILL BE HOT)

5. Examine your workpiece. Consult the workshop instructor on how to improve your weld.

GOOD POOR POOR

70

11.5.B Corner Joint

1. Check and ensure that the workpieces are straight and flat. 2. Tack weld the workpieces into a T-shaped joint.

3. Use a face shield, mark/touch the electrode to produce an arc. When there is a spark, ensure that the angle and distance are correct for welding the workpiece. Move the electrode slowly while pressing the electrode until it reaches the end of the workpiece. When reaching the end of the workpiece, raise the electrode and turn it away from the workpiece

4. With your safety goggles on, remove the slag and examine the weld by chipping with a hammer or wire brush. (USE EXTREME CARE AS THE METAL WILL BE HOT)

71

5. Examine your workpiece. Consult the workshop instructor on how to improve your weld.

GOOD POOR POOR 11.6 Project Report

A. Results

B. Discussion

72

C. Conclusion

73

MCB1043: Manufacturing Technology

Workshop Practical Manual May, 2011 Semester

Student Name: Student ID:

Date Actual Group

Number

Attendance (Technician’s

Stamp)

Lab Manual Marks

Work Piece Marks

Conventional Milling Conventional Lathe CNC Milling 1 CNC Milling 2 CNC Lathe 1 CNC Lathe 2 CNC Bridgeport Arc Welding 1 Arc Welding 2 Arc Welding 3 Metrology

Note: All lab reports must be completed by the end of each lab session. Late submissions will not be accepted.

Receive By: Date/Time: _____________

74

SAFETY AGREEMENT

I, named as below, fully understand all the regulations pertaining to the Health, Safety and Environment in the laboratory as listed in Appendix J of this manual, and therefore shall abide and follow all the rules and instructions. Name: IC/Passport No: Date: Signature:

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12. Metrology

12.1 Objective: To familiarize with the operation of measuring gauges, instruments and equipment.

12.2 Workshop objectives. By the end of this workshop, students should be able to: 1. Utilize measuring instruments in the proper manner.

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12.3 Project Report: Metrology

1. Surface Plate Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

77

2. V-block Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

78

3. Vernier caliper Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

79

4. Screw thread micrometer Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

80

5. Outside micrometer Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

81

6. Inside micrometer Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

82

7. Depth micrometer Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

83

8. Precision square Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

84

9. Dial indicator Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

85

10. Thickness gauge Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

86

11. Height gauges Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

87

12. Radius gauge Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

88

13. Pitch gauge Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

89

14. Telescopic gauge Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

90

15. Bore gauge Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

91

16. Bevel protractor Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

92

17. Sine bar Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

93

18. Coordinate measuring machine Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

94

19. Laser digitizer Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

95

20. Non-contact measuring machine Function

Resolution

Procedure

Results of sample measurement

Applications

Discussion

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APPENDIX A -Procedures and Guidelines for Milling Project Stock squaring To create a square corner on a part, first orient an already finished edge vertically in the vise. Set a machinist's ( L) square against the finished edge and the bottom of the vise. Lightly tap the part with a plastic hammer to align it with the L Square. Clamp the vise down securely. Now the top edge of the part is ready to be milled. 1. Setup the work piece by placing it onto the vice. 2. Use a parallel bar to raise the workpiece. 3. Secure the workpiece by tightening the vise. 4. Bring the face mill cutter slowly to touch the surface of the material. 5. Move the face mill cutter away. 6. Turn the quill to raise the table 0.5 mm per cut. 7. Mill the surface until a flat surface is achieved 8. Re-setup the workpiece to the next side in order to obtain a 90 angle from the first milled

side. 9. Ensure that you use an ‘L’ square to align the workpiece before you tighten the vise. 10. Repeat steps 2 to 7. 11. Use the height gauge to mark off the remaining material. 12. Cut off the remaining material until the dimensions 38mm x 38mm x 25mm are achieved. Marking 1. Using the center marker, punch the center of the workpiece. 2. Set the height gauge to the drawing and mark the workpiece. 3. Set the height gauge again and mark on the perpendicular side from the the previous

marking. 4. Make a center punch on the center of the work piece. Milling & Drilling 1. Secure the workpiece on the milling vise again with the marking facing up. 2. By using the end mill cutter, mill off the marked portion. 3. Secure the workpiece to a drilling vise. 4. By using diameter 10.25mm drill bit, drill through the workpiece at the center punch mark. 5. Unclamp the work piece. Tapping 1. Secure the workpiece onto the vise. 2. Tap a hole using an appropriate tap.

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Troubleshooting Guide for Milling

98

APPENDIX B - Procedures and Guidelines for Lathe Project

1. Setup the raw material and tighten the chuck. 2. Face one end first (facing process). 3. Mark the workpiece to 90 mm and 50 mm by using a vernier height gauge. 4. Re-clamp the raw material and ensure that the faced side is inside the chuck. 5. Cut the material to 90 mm by using straight turning and facing processes. 6. Center-drill a hole on both ends 7. Use straight turning process in order to obtain 22 mm and 50 mm length. 8. Re-set the work piece to the other side for the next process. 9. Machine to 18 mm and 40 mm length by using straight turning process. 10. Perform a marking process by using a vernier height gauge in order to mark 5 mm

and 20 mm in length. 11. On the 5mm length mark, perform a grooving/necking process until 8 mm is

achieved. 12. Perform a turning process to 11.8 mm and length 15 mm. 13. Turn Compound Rest to 30 to produce a chamfer according to the project diagram. 14. Re-clamp the raw material and perform an external threading by using a Tap & Die

set M12 X 1.75. 15. Setup raw material at the chuck again and use a live center to secure raw material. 16. Perform taper turning to obtain 12 mm at the smaller end with angle 8.

Troubleshooting Guide for Turning

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APPENDIX C - Procedures and Guidelines for CNC Milling Project Start-up and initialization procedure

1. Turn on main power switch on wall 2. Turn on Voltage Stabilizer 3. Turn on computer console 4. Turn on the controller unit 5. Release the Emergency Stop 6. Open the air valve and ensure that the pressure is at 6.9 Bar (100lbs/ft2) 7. From the MS-DOS command prompt, change directory to XLMILL. Run the Fanuc desktop

tutor software by typing in FANUCMD Manual machine tool operation

1. Return the cutting tool to its home position using the control keypad by pressing [HOME], [TRVRS].

2. Press T and enter the tool number to perform a tool change 3. Specify the spindle speed by pressing S and keying in the desired RPM. Turn on the

spindle by pressing [Spindle CW]. Change the spindle speed when the spindle is still spinning by pressing S.

4. Press [JOG] to toggle between step or continous movement of the tool. Adjust the feedrate of the tool by using the up/down cursor keys. Jog the cutting tool using step as well as continuous movement to various positions.

5. Turn off the spindle 6. Return the cutting tool to its home position

Numerical control operation I) Part programming and simulation

1. Press [F10] to display the main menu. To start programming and simulating the NC code, press Edit & Simulate.

2. Key in the NC program using the control keypad. Alternatively, you may quit the software ([F10], Quit) and key in the program from MS-DOS. Once you have a program saved, press [F3] from the Fanuc software to load the program.

3. Before you can begin the simulation, set the workpiece datum, which is the (0,0) position. To set the workpiece datum, press [F9] and select Set datum. Select where you want the (0,0) position to be, relative to the workpiece.

4. Begin the simulation by pressing [F9] and selecting Run program.

II) NC machining

1. Plan the operations for producing the part shown in the technical drawing (obtain the technical drawing from your lab instructor).

2. Construct a part program to machine the component and save it into a file. 3. Simulate the program to ensure that there are no errors. 4. Machine the part using the NC part program that you have developed: i. Return the cutting tool to its home position ii. Ensure that the workpiece is firmly secured iii. Jog the cutting tool to the workpiece datum iv. Commence operation by pressing [Auto], [Cycle start]

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5. Perform the shutdown procedure. 6. Clean the machine and surrounding work area. 7. Inspect the machined part for inconsistencies with the original design.

Perform measurements on the machined part if and where possible.

Summary of Relevant G and M Codes

GG0000 RRaappiidd TTrraavveerrssee ooff ffaasstt TTrraavveerrssee GG0011 LLiinneeaarr IInntteerrppoollaattiioonn GG0022 CClloocckkwwiissee CCiirrccuullaarr IInntteerrppoollaattiioonn GG0033 CCoouunntteerr--CClloocckkwwiissee CCiirrccuullaarr IInntteerrppoollaattiioonn GG2200 IImmppeerriiaall UUnniittss GG2211 MMeettrriicc UUnniittss GG2288 AAuuttoommaattiicc ZZeerroo RReettuurrnn GG4400 CCaanncceell ccuutttteerr ccoommppeennssaattiioonn GG7711 RRoouugghh oouutt pprrooffiillee bbyy ttuurrnniinngg GG7700 FFiinniisshhiinngg CCyyccllee GG9900 AAbbssoolluuttee MMoovveemmeenntt GG9911 IInnccrreemmeennttaall MMoovveemmeenntt GG9922 PPrrooggrraammmmiinngg ooff tthhee ccoooorrddiinnaattee ssyysstteemm

GG9944 FFeeeedd rraattee iinn mmmm//mmiinn oorr iinn//mmiinn ((GG9988 ppeerrffoorrmmss tthhee ssaammee ffuunnccttiioonn iinn tthhee CCNNCC llaatthhee)) GG9955 FFeeeedd rraattee iinn mmmm//rreevv oorr iinn//rreevv MM0033 SSttaarrtt SSppiinnddllee MM0055 SSttoopp SSppiinnddllee MM0066 CChhaannggee TTooooll MM3300 EEnndd ooff PPrrooggrraamm FF FFeeeedd ccooddee ((FF ccooddee)) SS SSppeeeedd ccooddee ((SS ccooddee)) TT TTooooll ccooddee ((TT ccooddee))

101

APPENDIX D - Procedures and Guidelines for CNC Lathe Project Start-up and initialization procedure

1. Turn on main power switch on wall 2. Turn on Voltage Stabilizer 3. Turn on computer console 4. Turn on the controller unit 5. Release the Emergency Stop 6. From the MS-DOS command prompt, change directory to XLTURN. Run the Fanuc

desktop tutor software by typing in FLSTEP. Manual machine tool operation

1. Return the cutting tool to its home position using the control keypad by pressing [HOME],[+Z] or [-Z], [+X] or [-X].

2. Press T and enter the tool number to perform a tool change 3. Ensure that you are in the JOG mode by pressing [JOG]. 4. Specify the spindle speed by pressing S and keying in the desired RPM. Turn on the

spindle by pressing [Spindle CW]. Change the spindle speed when the spindle is still spinning by pressing S.

5. Press [JOG] to toggle between step or continous movement of the tool. Adjust the feedrate of the tool by using the up/down cursor keys. Jog the cutting tool using step as well as continuous movement to various positions.

6. Turn off the spindle 7. Return the cutting tool to its home position

Numerical control operation

I)Part programming and simulation

1. Press [F10] to display the main menu. To start programming and simulating the NC code, press Edit & Simulate.

2. Key in the NC program using the control keypad. Alternatively, you may quit the software ([F10], Quit) and key in the program from MS-DOS. Once you have a program saved, press [F3] from the Fanuc software to load the program.

3. Press [F9] to access the simulation menu and select Set Tooling to select the approprate tool for visualization.

4. Begin the simulation by selecting Run program. 5. Explore other functions from the simulation menu:

II) NC machining 1. Plan the operations for producing the part shown in the technical drawing (obtain the

technical drawing from your lab instructor). 2. Construct a part program to machine the component and save it into a file. 3. Simulate the program to ensure that there are no errors. 4. Machine the part using the NC part program that you have developed 5. Return the cutting tool to its home position 6. Ensure that you have the correct tool in position 7. Ensure that the workpiece is firmly secured

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8. Check to ensure that the tool offsets are zeroed by selecting Tool Offsets. Then press cursor up/down to the tool that you have specified in your program. Press M and the corresponding axis (X or Z) to edit the tool offset. Press /#EOB to confirm and then Cancel to exit.

9. Shave a thin layer off the circumference of the workpiece and set the X offset: 10. Jog the tool to touch the circumference of the circle slightly 11. Jog the tool in the +Z direction so until the tool is about one centimeter off the face of

the workpiece 12. Jog the tool in the –X direction so that the tool will cut approximately 0.3mm from the

circumference of the workpiece. 13. Activate the spindle to an appropriate speed 14. Jog the tool in the –Z direction to start shaving a layer off the workpiece 15. Turn off the spindle 16. Measure the diameter of the workpiece 17. Key in the diameter into the X offset setting 18. Shave a thin layer off the face of the workpiece and set the Z offset: 19. Jog the tool to touch the face of the workpiece slightly. The tool should be close to the

edge of the face of the workpiece 20. Jog the tool in the +X direction until the tool is about one centimeter off from the

circumference of the workpiece 21. Jog the tool in the –Z direction so that the tool will cut approximately 0.3mm from the

face of the workpiece 22. Activate the spindle to an appropriate speed. 23. Jog the tool in the –X direction to start shaving a layer off the workpiece 24. Turn off the spindle 25. Set the Z value into the Z offset setting 26. Save the tool offsets and enter an offset number 27. Load the program and commence operation by pressing [Auto], [Cycle start]. 28. Perform the shutdown procedure 29. Clean the machine and surrounding work area 30. Inspect the machined part for inconsistencies with the original design 31. Perform measurements on the machined part if and where possible

Summary of Relevant G and M Codes

GG0000 RRaappiidd TTrraavveerrssee ooff ffaasstt TTrraavveerrssee GG0011 LLiinneeaarr IInntteerrppoollaattiioonn GG0022 CClloocckkwwiissee CCiirrccuullaarr IInntteerrppoollaattiioonn GG0033 CCoouunntteerr--CClloocckkwwiissee CCiirrccuullaarr IInntteerrppoollaattiioonn GG2200 IImmppeerriiaall UUnniittss GG2211 MMeettrriicc UUnniittss GG2288 AAuuttoommaattiicc ZZeerroo RReettuurrnn GG4400 CCaanncceell ccuutttteerr ccoommppeennssaattiioonn GG7711 RRoouugghh oouutt pprrooffiillee bbyy ttuurrnniinngg GG7700 FFiinniisshhiinngg CCyyccllee GG9900 AAbbssoolluuttee MMoovveemmeenntt GG9911 IInnccrreemmeennttaall MMoovveemmeenntt GG9922 PPrrooggrraammmmiinngg ooff tthhee ccoooorrddiinnaattee ssyysstteemm

GG9944 FFeeeedd rraattee iinn mmmm//mmiinn oorr iinn//mmiinn ((GG9988 ppeerrffoorrmmss tthhee ssaammee ffuunnccttiioonn iinn tthhee CCNNCC llaatthhee)) GG9955 FFeeeedd rraattee iinn mmmm//rreevv oorr iinn//rreevv MM0033 SSttaarrtt SSppiinnddllee MM0055 SSttoopp SSppiinnddllee MM0066 CChhaannggee TTooooll MM3300 EEnndd ooff PPrrooggrraamm FF FFeeeedd ccooddee ((FF ccooddee)) SS SSppeeeedd ccooddee ((SS ccooddee)) TT TTooooll ccooddee ((TT ccooddee))

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Recommended machining parameters for CNC Lathe Workpiece Material: Aluminium

OPERATION SPINDLE SPEED, rpm

FEED, mm/min

DEPTH OF CUT, mm

Turning 1000-1500 45-55 0.5-1.0 Grooving 600-800 15-25 0.25-0.5 Threading 300-350 0.03-0.04 Thread Parameter table

NOMINAL DIA. mm

PITCH mm (F) CORE DIA. X Bolt Nut

HEIGHT OF THREAD mm (P)

M 2.5 0.45 1.948 2.013 0.276 M 3 0.5 2.387 2.459 0.307 M 4 0.7 3.141 3.242 0.429 M 5 0.8 4.019 4.134 0.491 M 6 1 4.773 4.918 0.613 M 8 1.25 6.466 6.647 0.767 M 10 1.5 8.160 8.376 0.920 M 12 1.75 9.853 10.106 1.074 M 16 2 13.546 13.835 1.227 M 20 2.5 16.933 17.294 1.534 M 24 3 20.320 20.752 1.840 M 30 3.5 25.706 26.211 2.147 M 33 3.5 28.706 29.211 2.147 M 36 4 31.903 31.67 2.454 M 8 X 1 1 6.773 6.918 0.613 M 10 X 1.25 1.25 8.466 8.647 0.767 M 12 X 1.25 1.25 10.466 10.767 0.767 M 16 X 1.5 1.5 14.16 14.376 0.920 M 20 X 1.5 1.5 18.16 18.376 0.920 M 24 X 2 2 21.546 21.835 1.227 M 30 X 2 2 27.546 27.835 1.227 M 36 X 3 3 32.32 35.752 1.840

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APPENDIX E – Procedures for Arc Welding Bead forming

1. Ensure that the electrodes are clamped with the positive to the arc welding machine

and the negative source on the workpiece (worktable). Check the amperage of the arc welding machine.

2. Place the workpiece on the worktable. Use a face shield. Mark/touch the electrode to the workpiece to produce arc.

3. When there is a spark, ensure that the angle and the distance are right for arc welding. 4. Move the electrode slowly while pressing the electrode until it reaches the end of the

workpiece. This will extinguish the flame. 5. Use a chipping hammer to remove burrs. Ensure that goggles are used as the burrs are

hot and brittle.

Bead forming Electrode angle Electrode distance

APPENDIX F - Procedures and Guidelines for CNC Bridgeport Milling Project

Machine Start Up Procedure

i. Turn on air compressor. ii. Turn on main power switch on wall. iii. Turn on machine power switch located behind the machine. iv. Turn on control on/off switch located on the control panel. v. Release the Emergency Stop Button

Work Piece Datum Set Up Procedure

i. Set up X and Y Datum

Move edge finder to one of work piece side at X axis using [MPG] mode. Set X value to zero using the control keypad by pressing

[POST] [REL] [OPRT] [X] [ORIGIN]

75o

3mm

electrode

electrode weld direction

105

Move edge finder to the other side of work piece at X axis. Then divide the actual X value by two, in order to get the center of work piece. Move the edge finder to the center of work piece at X axis. Set again X value to zero using the control keypad by pressing

[X] [ORIGIN]

Move edge finder to one of work piece side at Y axis. Set Y value to zero using the control keypad by pressing

[Y] [ORIGIN] Move edge finder to the other side of work piece at Y axis. Then divide the actual Y value by two, in order to get the center of work piece. Move the edge finder to the center of work piece at Y axis. Set again Y value to zero using the control keypad by pressing

[Y] [ORIGIN]

Use Macros Program to setup the X and Y datum (0,0) in the system, using the control keypad by pressing

[PROGRAM] [AUTO] [Type file name O3214 and press down arrow] [CYCLE START] ii. Set up Z Datum

Select the require tool. Run the tool in [MDI] mode with spindle speed 500 – 1000rpm. With [MPG] mode, move down the tool at Z axis until touch with the work piece

surface. Use Macros Program to setup the Z datum in the system, using the control keypad by

pressing [CUSTOM] [F4]

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APPENDIX G – Workshop Rules and Penalties Workshop rules 1. Download laboratory manual, print the entire document and bring to your first lab

session. The lab manual must be kept at the lab and all reports must be completed during the lab session. The manual must not be taken out of the lab.

2. Bring textbook to lab as a reference. 3. Lab sessions will be assigned to you. Change of times can only be allowed for

emergencies and official university functions. Change of lab times must be swapped with another student. Inform technicians 3 days before date of lab. Otherwise penalties (at instructor’s discretion) will be imposed.

4. Come to lab on time. Missing a lab may lead you to being barred from the final examination. Penalties 1. Plagiarism : 50% off the mark if found texts reproduced from Laboratory

Manual, senior or classmates’ reports, or other sources etc. 2. Safety Violations : -5 marks

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APPENDIX H - Report Writing Guidelines The writing in the report reflects the care that went into the experimental work.

Spelling and grammar are important components to be taken care of. Neatness

counts. Label and name figures properly.

1. Objectives:

Identify all the objectives relevant to the workshop. Objectives are important

to state because these objectives are analyzed in the conclusions to

determine whether the project succeeded.

5. Procedure:

In you own words, Write out the actual experimental procedure followed

(which might differ slightly from the standard manual). List the step-by-step

summary of procedures.

2. Results:

Describe the output of your project (eg: A 10.04-mm diameter hole was

produced on the face of the workpiece) along with relevant sketches if

necessary. Measurements of important dimensions should also be included.

Observations such as chatter marks, poor surface finish or flash deposits

should also be included.

3. Discussion:

In this section, the results presented are analyzed and interpreted. (Explain

WHY you got those results!). Also discuss how to overcome undesirable

results in the future. The logic in the discussion section should support the

conclusion section.

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Example:

Bad:- The surface is very rough because of poor machining practice.

Good:-Potential causes of the poor surface finish in this project are

excessive vibration and built up edge on the cutting tool.

Vibration was mainly due to lack of stiffness in clamping of the

workpiece while built up edge was due to the high depth of cut

used. Surface finish therefore, can be improved by properly

clamping the workpiece and reducing the depth of cut.

4. Conclusion:

This section discusses the results in the context of the entire experiment; the

objectives mentioned are revisited/examined to determine whether the project

succeeded.

Example:

Good:- A workpiece was successfully machined according to the

specifications in the engineering drawing. The top surface

however, exibited somewhat poor surface finish due to built

up edge on the cutting tool and workpiece vibration. The

operations performed included face milling, tapping and end

milling.

5. References:

List of reference books or website used. They should follow the following

format e.g.:

1. Timonshenko, S., Woinowsky-Krieger, 1959. Theory of Plates and Shells.

McGraw-Hill, New York. p 203 – 210.

2. www.plint.co.uk/at2/leaflet/te76.htm

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APPENDIX I – Safety Precautions

Introduction

Health and Safety at Work Act 1994, it is based on the self-regulation concept. It

is a legal requirement that:

To ensure safety and health of themselves as well as others who may be

exposed to risks arising from their work activities

Through effective and efficient safety management systems suited to the

nature of the work activity at the workplace

Safe Practice for Engineering Trainees

You should acquire and practice the safe methods of your chosen skill and by the

use of intelligence; initiative and knowledge ensure the safety of the workshop

and remove the risk of injury or disablement to yourself and your colleagues.

Safety Awareness Genuine safety comes from following the example set by your instructor and

developing ‘safety awareness’ which is the same as ‘road sense’ when driving.

Major Potential Hazards

The lists below are the major potential hazard in the Materials Laboratory

1. Injury through misuse – applies to all equipment

2. Poisoning from toxic materials – Nital, HCl, etc.

3. Injury from electric shock – All equipment

4. Injury from heavy equipment – All equipment

5. Injury from sharp objects or edges – Brittle Fracture Testing, etc.

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General Instructions

The general instructions are given as follows:

1. Never misuse any equipment

2. Know the fire exit and locations of safety equipment

3. Avoid overcrowding at one place

4. Avoid closing to a source of heat/any high temperature component

5. Report any accident, damage or near miss to the laboratory staff.

Special Instructions 1. Wear suitable clothes (white lab coat is required)

2. Wear protective glasses, gloves or other protection equipment when required

3. Do not bring or consume foods/drinks in the laboratory.

4. Smoking is strictly prohibited.

5. Wear shoes. Sandals and slippers are not allowed.

6. Playful or prankish behavior will not be tolerated in the laboratory.

Additional Safety Instructions 1. You should be aware of the locations of the emergency switch buttons,

which can be used to cut off all electric circuits in the laboratory rooms,

except the lights.

2. You should be aware of the locations of fire extinguishers and fire alarms in

the laboratory.

3. Any malfunctioning of laboratory equipment should be promptly reported to

your instructor, as should plugged drains or other safety hazards.

4. You should be aware of the location of the first aid kit and know how to use

the emergency eyewash (and shower) in the materials lab.

6. Minor cuts or bums should not be neglected. You should report them

immediately to the instructor, who will decide whether to carry out first aid

procedures or to send you to the university medical centre for treatment.

111