Stress Tensor
Strain Tensor
Normal force, shear
force, torsional
moment and
bending moment all
contribute to the
state of stress
State of stress results in a state of strain
x
xy
xz
x xy xz
yx y yz
zx zy z
3D Constitutive relationship
Triaxial
SDLUIIDN (15.33)
Known: A spur gear smd rerhlcer is driven by an electric motor and drives a load
involving r'moderate shock“. The gear teeth are standard full depth and of speciﬁed
geometryr and material. Required life is 1‘35 pinion revelations for a sp
SULUTIDN {6.22)
Known: ﬁve states of hiattial suess are given.
Find: Based en using three different failure theories, list the five states in nrder crf
increased likelihood of causing failure.
Schematic and Given Date:
”a
3
.4:
P.
Lu.
Cl
yield strength of
SOLUTION (3.16)
Known: Four knovvn standard RR. Moore specimens are given.
Find: Estimate the long—life fatigue strength for reversed torsional loading. (State
whether it is for 103 or 5 X 103 cycles.)
Schematic and Given Data:
Wrought aluminum
5, = 250 l
SOLUTION (10.6}
Known: A double—threaded Acme screw of known major diameter is used in a jack
having a plain thrust collar of known mean diameter. Coefficients of nmning friction
are estimated as 0 .10 for the collar and 0.13 for the screw.
Find:
(a) Dete
SOLUTION (11.3)
Known: Two steel plates with SF : 425 NIPa are butt welded together with E70 series
welding rods. The weld length is known.
Find: Determine the maximum tensile load that can be applied to the joint with a safety
factor of 4.
Schematic and
SDLUTTDN (14.12)
Known: A No. 203 radial hall hearing carries a radial load of zoo lb and a thrust load
of 1513 lb at 1800 rpm.
Find: Determine the hearing B—lﬂ life.
Schematic and Given Data:
No. 2'03 Radial Bearing
F1— : zoo N, Ft=15ﬁN
90% reliability
s
SOLUTION (5 .36)
Known: The dimensions of a solid round steel with S}: : 350 MPa are known.
Find: With a safety factor of 4, what axial compressive load can be applied if:
(a) Both ends are hinged?
(b) Both ends are built in?
Schematic and Given Data:
1
SOLUTION (5.21)
Known: Figure P521 is given.
Find: Calculate the angular and linear displacements of point A.
Schematic and Given Data:
Assumption: The deﬂection is elastic.
Analysis:
1. For linear deﬂection:
3
. é : PL
From Table 5.1 (Case 5),
SOLUTION (2.14new)
Known: The geometry and the loads acting on a pinned assembly are given.
Find: Draw a free-body diagram for the assembly and determine the magnitude of the
forces acting on each member of the assembly.
Schematic and Given Data:
Assump
SOLUTION (4.11)
Known: A force, P : 12,325 lb, loads the pinned joint shown in Fig. 4.4. The pin is
made of AN SI 1040 steel with S11 : 90.0 ksi (where Sus : 0.62 S“).
Find: Determine the minimum diameter pin required to avoid pin shear failure.
Schematic
Fatiguestrength S n S n C L CG C S CT C R
Springstresses
Tr 16T 8FD
J d 3 d 3
WithWahlcorrection
C
Withothercorrection
D
d
Kw
8FD
d 3
8 FD
Ks
d 3
Springdeflection
8D 3 N
F
Gd 4
s 0.45Su
for ferrous without presetting
s 0.35Su
for nonferrous and austeni
7)
(20 pts) A pair of helical gears are used with a 2000 rpm electric motor, stepping down the revolutions per minute
to 500 rpm at the pinion with moderate shock. The 25-tooth pinion has a
Pn
= 8, b = 2 inches, ~n = 20 deg., and \If =
26 deg. The hardnes
PROBLEM 3.5
KNOWN: Thermal conductivities and thicknesses of original wall, insulation layer, and glass layer.
Interior and exterior air temperatures and convection heat transfer coefficients.
FIND: Heat flux through original and retrofitted walls.
SCHEMA
Survey results
60
Chapter 2-5: Reveiws
50
40
30
John E. Novotny, Ph.D.
A
20
B
10
0
University of Vermont, School of Engineering,
Mechanical Engineering Program, Fall 2015
Method of sections
Locate section
Method of sections
Place coordinate
system
Perp