Springs

Question 1

Max normal stress in a coil spring

Answer 1

σmax = [+/- T d / 2 J] + [F / A]

Question 2

What type of spring is good in high load situations

Answer 2

Leaf springs

Question 3

What type of spring is good in rotational situations

Answer 3

Torsion spring

Question 4

What do extension springs need to engage the spring

Answer 4

Initial tension force

Question 5

What can compression springs be combined with for additional support

Answer 5

a shaft

Question 6

Heavy duty springs go through the process of ….. after forming

Answer 6

heat treatment

Question 7

L0:

Answer 7

free length

no load

Question 8

L1:

Answer 8

installed length

preload

Question 9

L2:

Answer 9

operating length

max. working load

Question 10

Lc:

Answer 10

solid length

closed load

Question 11

Closed length eqs

Answer 11

Lc = N d

Question 12

N eqs in the closed spring length eqs

what are Na and E

Answer 12

N = Na + E

Na: num. of active turns
E: ends

Question 13

PLAIN ENDS num. of active turns

Answer 13

N = Na

Question 14

PLAIN GROUND-ENDS num. of active turns

Answer 14

N = Na + 1

Question 15

SQUARED ENDS num. of active turns

Answer 15

N = Na + 2

Question 16

SQUARED GROUND ENDS num. of active turns

Answer 16

N = Na + 2

Question 17

Spring Index

Answer 17

C = D / d

Question 18

What is D in the Spring Index eqs

Answer 18

Mean diam.

Question 19

Outer diam. using Mean diam.

Answer 19

Do = D + d

Question 20

Inner diam. using Mean diam.

Answer 20

Di = D - d

Question 21

Hooke’s Law

Answer 21

F = kδ

Question 22

Torsional stress eqs in terms of θ

Answer 22

θ = T Lw / J G

Question 23

Deflection eqs

Answer 23

δ = (8 F D^3 Na) / (d^4 G)

Question 24

Deflection eqs using C

Answer 24

δ = (8 F C^3 Na) / (d G)

Question 25

Shear stress in a spring

Answer 25

τmax = (T r / J) + (F / A)

Question 26

Ks is

Answer 26

shear factor

Question 27

Kw is

Answer 27

Wahl factor

Question 28

Why use Kw instead of Ks in a scenario

Answer 28

Because Wahl factor takes into account cyclic loading

Question 29

Common sring index values

Answer 29

4 < C < 10

Question 30

How to check for buckling

Answer 30

L0 < 5D

Question 31

Relationship of max shear stress and Ultimate Tensile Strength

Answer 31

τmax < 0.55 Sut