# Chapter15-Keys and Couplings¶

## Ex1-pg332¶

In [1]:
import math

print('MACHINE DESIGN \n Timothy H. Wentzell, P.E. \n EXAMPLE-15.1 Page No.332\n');

##Torque
P=5.;
n=1750.;
T=63000.*P/n;

print'%s %.2f %s '%('\n Torque = ',T,' in-lb.');

##Length of key for shear
Su=61000.;
Ss=0.5*Su;
b=0.125;
D=0.5;
Ls1=2*T/(Ss*b*D);
SF=2.5;

Ls=SF*Ls1;

print'%s %.2f %s '%('\n Length of key for shear = ',Ls,' in.');

##Length of key for compression
Sc=51000.;
t=0.125;
Lc1=4.*T/(Sc*t*D);

Lc=SF*Lc1;

print'%s %.2f %s '%('\n Length of key for compression = ',Lc,' in.');

MACHINE DESIGN
Timothy H. Wentzell, P.E.
EXAMPLE-15.1 Page No.332

Torque =  180.00  in-lb.

Length of key for shear =  0.47  in.

Length of key for compression =  0.56  in.


## Ex2-pg335¶

In [2]:
import math

print('MACHINE DESIGN \n Timothy H. Wentzell, P.E. \n EXAMPLE-15.2 Page No.335\n');

##Torque capacity
Ss=30500.;
D=1.;
L=2.;
T1=Ss*math.pi*D**2*L/16.;

SF=2.;

T=T1/SF;

print'%s %.2f %s '%('\n Torque capacity 1 = ',T,' in-lb.');
n=6.;
d=0.81;
A=(D-d)*L*n/2.;

S=1000.;
rm=(1.+0.810)/4.;

T2=S*A*rm;

print'%s %.2f %s '%('\n Torque capacity 2 = ',T2,' in-lb.');

MACHINE DESIGN
Timothy H. Wentzell, P.E.
EXAMPLE-15.2 Page No.335

Torque capacity 1 =  5988.66  in-lb.

Torque capacity 2 =  515.85  in-lb.