Mechanical Engineering Exam  >  Mechanical Engineering Questions  >  A 20o full depth involute spur pinion of 4 mm... Start Learning for Free
A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.
Q. 
Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material is
  • a)
    242.0
  • b)
    166.5
  • c)
    121.0
  • d)
    74.0
Correct answer is option 'B'. Can you explain this answer?
Verified Answer
A 20o full depth involute spur pinion of 4 mm module and 21 teeth is t...
From Lewis equation

Minimum allowable (working stress)
View all questions of this test
Most Upvoted Answer
A 20o full depth involute spur pinion of 4 mm module and 21 teeth is t...
Problem Statement: To find the minimum allowable stress for the gear material of a 20o full depth involute spur pinion.

Given data:
Module (m) = 4 mm
No. of teeth (N) = 21
Power transmitted (P) = 15 kW
Speed (N) = 960 rpm
Face width (b) = 25 mm
Tooth geometry factor (Y) = 0.32
Combined effect of dynamic load and allied factors intensifying the stress (K) = 1.5

Formula used:
Tangential force (Ft) = (2 × P × 10^3) / (π × N) ---(1)
Pitch diameter (D) = m × N ---(2)
Module factor (Km) = 1 ---(3)
Addendum (ha) = m ---(4)
Dedendum (hf) = 1.25 × m ---(5)
Tooth thickness (s) = π × m / 2 ---(6)
Contact ratio (C) = 1 ---(7)
Velocity factor (Kv) = 1 ---(8)
Dynamic factor (Kv) = ((C × Kv) / (C + Kv - 1))^(1/2) ---(9)
Dynamic load factor (Km) = 1 / (1 + Kf) ---(10)
Tooth load factor (Kf) = Y / (2 × Y - 1) ---(11)
Bending stress (σb) = (Ft × Km × Kv × Ks) / (b × m × Z × Y) ---(12)
Surface stress (σH) = Ft / (b × m × Y) ---(13)
Allowable bending stress (σba) = Sut / K ---(14)

Calculation:
Using equation (1), Ft = (2 × 15 × 10^3) / (π × 960) = 98.17 N
Using equation (2), D = 4 × 21 = 84 mm
Using equation (3), Km = 1
Using equation (4), ha = m = 4 mm
Using equation (5), hf = 1.25 × m = 5 mm
Using equation (6), s = π × m / 2 = 6.28 mm
Using equation (7), C = 1
Using equation (8), Kv = 1
Using equation (9), Kv = ((1 × 1) / (1 + 1 - 1))^(1/2) = 1
Using equation (11), Kf = Y / (2 × Y - 1) = 0.457
Using equation (10), Km = 1 / (1 + 0.457) = 0.686
Using equation (12), σb = (98.17 × 0.686 × 1 × 1) / (25 × 4 × 21 × 0.32) = 166.53 MPa
Using equation (13), σH = 98.17 / (25 × 4 × 0.32) = 30.58 MPa
Using equation (14), σba = Sut
Attention Mechanical Engineering Students!
To make sure you are not studying endlessly, EduRev has designed Mechanical Engineering study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Mechanical Engineering.
Explore Courses for Mechanical Engineering exam

Top Courses for Mechanical Engineering

A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.Q.Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material isa)242.0b)166.5c)121.0d)74.0Correct answer is option 'B'. Can you explain this answer?
Question Description
A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.Q.Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material isa)242.0b)166.5c)121.0d)74.0Correct answer is option 'B'. Can you explain this answer? for Mechanical Engineering 2024 is part of Mechanical Engineering preparation. The Question and answers have been prepared according to the Mechanical Engineering exam syllabus. Information about A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.Q.Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material isa)242.0b)166.5c)121.0d)74.0Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for Mechanical Engineering 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.Q.Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material isa)242.0b)166.5c)121.0d)74.0Correct answer is option 'B'. Can you explain this answer?.
Solutions for A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.Q.Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material isa)242.0b)166.5c)121.0d)74.0Correct answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for Mechanical Engineering. Download more important topics, notes, lectures and mock test series for Mechanical Engineering Exam by signing up for free.
Here you can find the meaning of A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.Q.Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material isa)242.0b)166.5c)121.0d)74.0Correct answer is option 'B'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.Q.Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material isa)242.0b)166.5c)121.0d)74.0Correct answer is option 'B'. Can you explain this answer?, a detailed solution for A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.Q.Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material isa)242.0b)166.5c)121.0d)74.0Correct answer is option 'B'. Can you explain this answer? has been provided alongside types of A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.Q.Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material isa)242.0b)166.5c)121.0d)74.0Correct answer is option 'B'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice A 20o full depth involute spur pinion of 4 mm module and 21 teeth is to transmit 15 kW at 960 rpm. Its face width is 25 mm.Q.Given that the tooth geometry factor is 0.32 and the combined effect of dynamic load and allied factors intensifying the stress is 1.5; the minimum allowable stress (in MPa) for the gear material isa)242.0b)166.5c)121.0d)74.0Correct answer is option 'B'. Can you explain this answer? tests, examples and also practice Mechanical Engineering tests.
Explore Courses for Mechanical Engineering exam

Top Courses for Mechanical Engineering

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev