MODULE NO. 3 VARIABLE STRESS ANALYSIS

Question 1

When do we use the goodman equation?

Answer 1

brittle materials

Question 2

when do we use the sodenberg eq?

Answer 2

ductile material

Question 3

goodman eq mnemonic?

Answer 3

MUANN

Question 4

Sodenberg eq mnemonic?

Answer 4

MYAN

Question 5

how to find the shear stress using Oy?

Answer 5

0.6Oy

Question 6

How to find the shear stress Tu?

Answer 6

0.75Ou

Question 7

how to find the endurance strength for ILF in axial/bending?

Answer 7

0.8 x endurance limit x surface factor

Question 8

how to find the endurance strength for IL in rotating bending?

Answer 8

0.8 x endurance limit x surface factor x size factor

Question 9

how to find the endurance strength for IL in torsion?

Answer 9

0.6 x endurance limit x surface factor x size factor

Question 10

how to find the endurance strength for DL in axial/bending?

Answer 10

0.8 X ANTILOG X SURFACE FACTOR

Question 11

how to find the endurance strength for DL in ROTATING BENDING?

Answer 11

0.8 X ANTILOG X SURFACE FACTOR X SIZE FACTOR

Question 12

how to find the endurance strength for DL in TORSION?

Answer 12

0.6 X ANTILOG X SURFACE FACTOR X SIZE FACTOR

Question 13

How do determine the endurance limit in wrought iron?

Answer 13

using BHN valur

Question 14

In wrought iron if BHNN is less than 400, what eq should we use to find the endurance limit?

Answer 14

0.5 Ou and 0.25 BHN

Question 15

In wrought iron if BHNN is more than than 400, what eq should we use to find the endurance limit?

Answer 15

0.4 Ou

Question 16

In cast steel what eq should we use to find the endurance limit?

Answer 16

0.4 Ou

Question 17

In cast iron what eq should we use to find the endurance limit?

Answer 17

0.35 Ou

Question 18

In nodular iron what eq should we use to find the endurance limit?

Answer 18

0.4Ou and 0.35Ou

Question 19

What equation should we use to find the endurance strength limit for DLB?

Answer 19

the antilog equation

Question 20

If the surface factor is not stated, what should we assume?

Answer 20

Machined

Question 21

WHat is the first value assumption is size factor and what is its expected answer?

Answer 21

0.85, and the answer should range from 0.5 to 2 in

Question 22

What are the three types of variable stresses?

Answer 22

reversed, repeated and fluctuating

Question 23

What is the value of Om and Oa in reversed stress?

Answer 23

Om/ Tm = 0
Oa/ Ta = Omax/Tmax

Question 24

What is the value of Om, Oa, Tm, Ta in repeated stress?

Answer 24

Mean stress = alternating stress

= Maxstress/ 2
= tensile stress max / 2

Question 25

What is the value of Om, Oa, Tm, Ta in fluctuating stress?

Answer 25

Om = Omax + Omin / 2 Oa = Omax - Omin / 2

Question 26

What is the difference between variable stress with and without stress concentration?

Answer 26

The value of kf/kfs

Question 27

How to get the value of kf/kfs?

Answer 27

kf/kfs = q(kt -1)+1

Question 28

How to get the value of q?

Answer 28

q = 1/ (1 + a/r)

Question 29

What figure can we find kt?

Answer 29

Figure AF8 to Af14