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diff --git a/3774/CH7/EX7.6/Ex7_6.sce b/3774/CH7/EX7.6/Ex7_6.sce
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+// exa 7.6 Pg 205
+clc;clear;close;
+
+// Given Data
+P=135;// kW
+N=120;// rpm
+tau_s=55;// MPa
+tau_b=45;// MPa
+tau_ci=175;// MPa
+sigma_ci=75;// MPa
+
+//sigma_cs=2*tau_s;// MPa
+
+//Tmax=1.5*Tm
+mu=0.15;// coefficient of friction
+
+//SHAFT DIAMETER
+// P= 2*%pi*N*Tm/60/1000 
+Tm=P/(2*%pi*N/60/1000);// N.m
+// %pi*d**3*tau_s/16= Tm
+d=(Tm/(%pi*tau_s/16)*1000)**(1/3);// mm
+d=ceil(d)
+printf('shaft diameter = %.2f mm.',d)
+Tmax=Tm;// N.m
+
+// HUB DIAMETER
+// Tmax=%pi/16*((d1**4-d**4)/d1)*tau_h
+tau_h=tau_ci;// MPa
+//d1*(Tmax/(%pi/16)/tau_h)-d1**4=d**4 -- eqn(1)
+Tmax=Tmax*1000;// N.mm
+p=[1 0 0 -Tmax/(%pi*tau_h/16) -d**4] ;// polynomial coefficients from eqn(1)
+d1=roots(p);// roots of poly 
+d1=d1(1);// mm (taking +ve value)
+d1=2*d;// mm (empirically adopted) 
+t1=(d1-d)/2;// mm (thickness of hub)
+printf('\n thickness of hub = %.f mm',t1)
+d4=d+t1;// mm (diameter of recess in flanges)
+printf('\n diameter of recess in flanges = %.f mm',d4)
+d3=4*d;// mm (outside diameter of protecting flange)
+printf('\n outside diameter of protecting flange = %.f mm.',d3)
+
+//Key size & Hub length
+b=d/4;// mm (width of key)
+l=1.5*d;// mm (length of key)
+printf('\n width of key = %.1f mm.',b)
+printf('\n length of key = %.f mm.',l) 
+t=b;// mm (thickness for square key)
+printf('\n thickness for square key = %.f mm',t)
+printf('\n Hub length = %.f mm',l)
+
+//Number of bolts
+n=ceil(4*d/150+3);// no. of bolts
+printf('\n Number of bolts = %.2f.',n)
+
+// Bolt diameter
+r2=1.5*d;// mm
+F=Tm*1000/r2/n;//N
+//(%pi/4)*db**2*tau_b=F
+db=sqrt(F/((%pi/4)*tau_b));// mm
+printf('\n Bolt diameter = %.2f mm. Use db=20 mm for design purpose',db)
+db=20;// mm (adopted for design)
+bolt_dia=db;//mm
+
+// Flange thickness
+t2=0.5*t1+6;// mm (empirically)
+printf('\n Flange thickness = %.1f mm. Use t=20 mm',t2)
+//F=n*db*t2*sigma_c
+sigma_ci=F/n/db/t2;// MPa
+//2*%pi*d1**2*tau*t2/4=Tmax
+tau=Tmax/(2*%pi*d1**2*t2/4);// MPa
+printf('\n permissible bearing stress in flange = %.2f MPa < 75 MPa',sigma_ci)
+printf('\n shearing of the flange at the junction with hub = %.2f MPa < 175 MPa.',tau)
+printf(' Values are acceptable.')
+
+// Check for crushing of bolt
+//n*db*t2*sigma_cb*d2/2=Tmax
+d2=d1+d;// mm
+db=bolt_dia;//mm
+sigma_cb=Tmax/(n*db*t2*d2/2);// MPa
+printf('\n permissible crushing strength of bolts = %.2f MPa < 60 MPa.',sigma_cb)
+printf(' Hence design is safe.')
+// Thickness of protecting flange
+t3=0.5*t2;// mm
+printf('\n Thickness of protecting flange = %.f mm', t3)
+// Hub overlap 
+ho=3;// mm (min)
+printf('\n Hub overlap = %.f mm (min)',ho)