Mechanical Engineering Assignment: Gear Design Problem Solution

This document presents a detailed solution for a gear design problem in mechanical engineering. The solution covers the design of four different gear sets, including the pinion and gear for each set. It begins by providing the given data, such as the number of teeth, power, RPM, gear ratio, and factor of safety. The solution then calculates the actual and design torque to be transmitted. Based on the design torque and available gears in the market, the module and diameter of the gears are determined. The document also includes the selection of gears from a catalogue, specifying part numbers, modules, pressure angles, rated torque, and materials. The gears are selected to ensure that the inlet and outlet shafts are inline. The calculations and selections are performed for both the pinion and the gear for each of the four gear sets, providing a comprehensive analysis of the gear design problem.

Solution for Problem no. 3
Gear no. 1 as per question no. 2
Given data
1. No. of teeth (Pinion): 66
2. No. of teeth (Gear): 80
3. Power: 40 KW
4. Rpm (Pinion) : 2000
5. Gear ratio: 1.5
6. Factor of Safety: 1.2
Gear Selection:
RPM (Gear) = RPM (Pinion)/ Gear ratio
=2000/1.2
=1667
Actual Torque to be transmitted: (PowerX9.5488)/Speed (gear)
=(40000X9.5488)/1667
=229.12 Nm
Design Torque to be transmitted: Actual Torque to be transmitted X Factor of Safety
=229.12X1.2
=275 Nm
Based on gears available in market, we have selected gear with module 2.5 as same can transmit this
amount of torque.
Module = 2.5
Module = diameter of gear / no. of teeth
No of teeth:
66
No of teeth:
80
PINION
GEAR

Diameter of Gear = Module X no. of teeth
= 2.5 X 80
= 200 mm
Selected gear from available Catalogue:
Part number: GEAHB
Module: 2.5
Pressure angle: 20 deg
Rated Torque: 396.36 Nm
Material: S45C Equivalent
Pinion Selection:
Actual Torque to be transmitted: (PowerX9.5488)/Speed (pinion)
=(40000X9.5488)/2000
=190.9 Nm
Design Torque to be transmitted: Actual Torque to be transmitted X Factor of Safety
=190.9X1.2
=229 Nm
Based on gears available in market, we have selected gear with module 3.0 as same can transmit this
amount of torque.
Module = 2.5
Module = diameter of gear / no. of teeth
Diameter of Gear = Module X no. of teeth
= 2.5 X 66
= 165 mm
Selected gear from available Catalogue:
Part number: GEAHB
Module: 2.5
Pressure angle: 20 deg
Rated Torque: 404.75 Nm
Material: S45C Equivalent

Gear no. 2 as per question no. 2
Given data
1. No. of teeth (Pinion): 50
2. No. of teeth (Gear): 70
3. Power: 40 KW
4. Rpm (Pinion) : 1667
5. Gear ratio: 1.4
6. Factor of Safety: 1.2
Gear Selection:
RPM (Gear) = RPM (Pinion)/ Gear ratio
=1667/1.4
=1191
Actual Torque to be transmitted: (PowerX9.5488)/Speed (gear)
=(40000X9.5488)/1191
=320.7 Nm
Design Torque to be transmitted: Actual Torque to be transmitted X Factor of Safety
=320.7X1.2
=385 Nm
Based on gears available in market, we have selected gear with module 2.5 as same can transmit this
amount of torque.
Module = 2.5
Module = diameter of gear / no. of teeth
Diameter of Gear = Module X no. of teeth
= 2.5 x 70
= 175 mm
Selected gear from available Catalogue:
Part number: GEAHB
Module: 2.5
Pressure angle: 20 deg
Rated Torque: 442.41 Nm
Material: S45C Equivalent
Pinion Selection:

Actual Torque to be transmitted: (PowerX9.5488)/Speed (Pinion)
=(40000X9.5488)/1667
=229.12 Nm
Design Torque to be transmitted: Actual Torque to be transmitted X Factor of Safety
=229.12X1.2
=275 Nm
Based on gears available in market, we have selected gear with module 2.5 as same can transmit this
amount of torque.
Module = 2.5
Module = diameter of gear / no. of teeth
Diameter of Gear = Module X no. of teeth
= 2.5 X 50
= 125 mm
Selected gear from available Catalogue:
Part number: GEAHB
Module: 2.5
Pressure angle: 20 deg
Rated Torque: 296.17 Nm
Material: S45C Equivalent

Gear no. 3 as per question no. 2
Given data
1. No. of teeth (Pinion): 40
2. No. of teeth (Gear): 60
3. Power: 40 KW
4. Rpm (Pinion) : 1667
5. Gear ratio: 1.5
6. Factor of Safety: 1.2
Gear Selection:
RPM (Gear) = RPM (Pinion)/ Gear ratio
=1191/1.5
=794
Actual Torque to be transmitted: (PowerX9.5488)/Speed (gear)
=(40000X9.5488)/794
=481 Nm
Design Torque to be transmitted: Actual Torque to be transmitted X Factor of Safety
=481X1.2
=577.25 Nm
Based on gears available in market, we have selected gear with module 3.0 as same can transmit this
amount of torque.
Module = 3.0
Module = diameter of gear / no. of teeth
Diameter of Gear = Module X no. of teeth
= 3.0 X 60
= 180 mm
Selected gear from available Catalogue:
Part number: GEAHB
Module: 3.0
Pressure angle: 20 deg
Rated Torque: 638.4 Nm
Material: S45C Equivalent
Pinion Selection:

Actual Torque to be transmitted: (PowerX9.5488)/Speed (pinion)
=(40000X9.5488)/1191
=320.7 Nm
Design Torque to be transmitted: Actual Torque to be transmitted X Factor of Safety
=320.7X1.2
=385 Nm
Based on gears available in market, we have selected gear with module 3.0 as same can transmit this
amount of torque.
Module = 3.0
Module = diameter of gear / no. of teeth
Diameter of Gear = Module X no. of teeth
= 3.0 X 40
= 120 mm
Selected gear from available Catalogue:
Part number: GEAHB
Module: 3.0
Pressure angle: 20 deg
Rated Torque: 386.49 Nm
Material: S45C Equivalent

Gear no. 4 as per question no. 2
Given data
1. No. of teeth (Pinion): 41
2. No. of teeth (Gear): 50
3. Power: 40 KW
4. Rpm (Pinion) : 1667
5. Gear ratio: 1.2
6. Factor of Safety: 1.2
Gear Selection:
RPM (Gear) = RPM (Pinion)/ Gear ratio
=794/1.2
=662
Actual Torque to be transmitted: (PowerX9.5488)/Speed (gear)
=(40000X9.5488)/662
=577 Nm
Design Torque to be transmitted: Actual Torque to be transmitted X Factor of Safety
=577X1.2
=692.3 Nm
Based on gears available in market, we have selected gear with module 4.0 as same can transmit this
amount of torque.
Module = 4.0
Module = diameter of gear / no. of teeth
Diameter of Gear = Module X no. of teeth
= 4.0 X 50
= 200 mm
Selected gear from available Catalogue:
Part number: KHK MSGA4-50
Module: 4.0
Pressure angle: 20 deg
Rated Torque: 3,650 Nm
Material: SCM415 (AISI 4115) Alloy Steel
Pinion Selection:

Actual Torque to be transmitted: (PowerX9.5488)/Speed (Pinion)
=(40000X9.5488)/794
=481 Nm
Design Torque to be transmitted: Actual Torque to be transmitted X Factor of Safety
=481X1.2
=577.25 Nm
Based on gears available in market, we have selected gear with module 4.0 as same can transmit this
amount of torque.
Module = 4.0
Module = diameter of gear / no. of teeth
Diameter of Gear = Module X no. of teeth
= 4.0 X 41
= 164 mm
Selected gear from available Catalogue:
Part number: KHK MSGA4-40
Module: 4.0
Pressure angle: 20 deg
Rated Torque: 2,290 Nm
Material: SCM415 (AISI 4115) Alloy Steel
Note: Gears are selected in such a way that inlet and outlet shaft are inline.