DESIGN WORK
1. A cold-finished shaft, AISI 1141, is to transmit power that varies from 200 to 100 and
back to 200 hp in each revolution at a speed of 600 rpm. The power is received by a 20in. spur gear A and delivered by a 10-in. spur gear C. The tangenti
SHAFT DESIGN UNDER PURE BENDING
Example:
A simply supported shaft has the distance between supports as 600mm. The load at the
centre is 15 kN. If the deflection at the centre is to be limited to 0.02mm, what should be the
diameter of the shaft? If the sha
VARIABLE STRESS ANALYSIS WITHOUT STRESS CONCENTRATION
EXAMPLE:
VARIABLE STRESS ANALYSIS WITHOUT STRESS CONCENTRATION
SAMPLE PROBLEMS
Problem No. 1
Problem No. 2
DESIGN WORK NO. 5
VARIABLE STRESS ANLYSISIS WITHOUT STRESS CONCENTRATION
Problem No. 1
Ans. a)
Sample Problem
A circular rod made of steel (y = 420 MPa) is subjected to a compressive load of 120 kN. Find
the suitable diameter of the rod taking a factor of safety as 2.
Given:
Yield stress, y = 420 MPa
Loa, F = 120 kN
Factor of safety = 3
Solution:
A
SHAFT DESIGN BASED ON CODE
SHAFT DESIGN BASED ON ASME CODE
PROBLEM
The problem is shown in the given figure. A pulley drive is transmitting power to
pinion, which in turn is transmitting power to some other machine element. Pulley and
pinion diameters are
Problem 1
A flanged bolt coupling consists of ten 20mm-diameter bolts spaced evenly around a circle of
400mm in diameter. Determine the torque capacity of the coupling if the allowable shearing
stress in the bolts is 40 MPa.
Solution:
T =PRn ;
T =ARn ;
P=
Basic Problem:
1. Find length required for compression, using lowest value of yield, which is
key value Sy = 51 ksi.
Solution :
Given: T = 180 in-lb; t = .125in; D = 0.5in
With FS = 2.5:
L = 2.5 (.226)
L = .565 inch
This would be the minimum length.
Sampl
Sample Problems
1. The beam shown has a circular cross section and supports a load F that
varies from 1000 lb to 3000 lb; it is machined from AISI C1020 steel, as
rolled. Determine the diameter D if r 0.2D and N 2 ; indefinite life.
2. The shaft shown is
DESIGN WORK NO. 1
DESIGN OF MEMBERS UNDER PURE TENSION
1. A coil chain of a crane required to carry a maximum load of 50 kN, is shown. Find the
diameter of the link stock, if the permissible tensile stress in the link material is not to exceed 75
MPa.
Giv
Shaft Design Under Pure Torsion
Problem:
What should be the diameter of the shaft if the deflection is not to exceed 1 degree in 25D. The
shaft rotates to a speed of 600 rpm and transmits 35 hp.
Solution:
Given;
P= 35 hp
N= 600 rpm
limit=1 degree
L= 25D
Machine Design I
DESIGN WORK 4: Machine Members under Pure Bending
1. A beam 5 inches wide by 4 inches high and 15 feet long is subjected to a concentrated
load of 2000 pound at a point 3 feet from one of the supports. Determine the maximum
fiber stress.
MACHINE MEMBERS UNDER PURE TORSION
BASIC PROBLEM:
1. A shaft rotates 600 rpm with minor shock.What should be its diameter if the deflection is not
to exceed 1 degree in 25D. The shaft transmits 35 hp.
Solution:
Given;
P= 35 hp
N= 600 rpm
limit=1 degree
L