{ "metadata": { "name": "", "signature": "sha256:5150ceeff814b37f327edfa239de19ec011af3bd135e00c577336409efc3a800" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 16:Torsion of Shafts and Springs" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 16.1,page no.675" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#Given\n", "#Variable declaration\n", "D=150 #Diameter of the shaft in mm\n", "tau=45 #Maximum shear stress in N/sq.mm\n", "\n", "#Calculation\n", "T=int(math.pi/16*tau*D**3)*1e-3 #Maximum torque transmitted by the shaft in N-m\n", "\n", "#Result\n", "print \"Maximum torque =\",T,\"N-m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Maximum torque = 29820.586 N-m\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 16.3,page no.677" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Given\n", "#Variable declaration\n", "Do=200 #Outer diameter in mm\n", "Di=100 #Inner diameter in mm\n", "tau=40 #Maximum shear stress in N/sq.mm\n", "\n", "#Calculation\n", "T=int(round((math.pi)/16*tau*((Do**4-Di**4)/Do),-1))*1e-3 #Maximum torque transmitted by the shaft in Nm\n", "\n", "#Result\n", "print \"Maximum torque transmitted by the shaft =\",T,\"Nm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Maximum torque transmitted by the shaft = 58904.86 Nm\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 16.7,page no.682" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "import math\n", "\n", "#Given\n", "#Variable declaration\n", "Do=120 #External diameter in mm\n", "P=300*1000 #Power in W\n", "N=200 #Speed in r.p.m\n", "tau=60 #Maximum shear stress in N/sq.mm\n", "\n", "#Calculation\n", "T=round((P*60)/(2*math.pi*N),1)*1e3 #Torque transmitted in Nmm \n", "Di=round(((Do**4)-((T*16*Do)/(math.pi*tau)))**(1/4),1) #Maximum internal diameter in mm\n", "\n", "#Result\n", "print \"Maximum Internal diameter =\",Di,\"mm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Maximum Internal diameter = 88.5 mm\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 16.8,page no.683" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#Given\n", "#Variable declaration\n", "D=15*10 #Diameter of shaft in mm\n", "P=150*1e3 #Power transmitted in W\n", "N=180 #Speed of shaft in r.p.m\n", "\n", "#Calculation\n", "T=(P*60)/(2*math.pi*N)*1e3 #Torque transmitted in Nmm\n", "tau=int((16*T)/(math.pi*D**3)) #Maximum shear stress in N/sq.mm\n", "\n", "#Result\n", "print \"Maximum shear stress =\",tau,\"N/mm^2\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Maximum shear stress = 12 N/mm^2\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 16.9,page no.683" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "import math\n", "#Given\n", "#Variable declaration\n", "P=300*1000 #Power in W\n", "N=100 #Speed in r.p.m\n", "tau=80 #Maximum shear stress in N/sq.mm\n", "\n", "#Calculation\n", "#case(a):\n", "T=(P*60)/(2*math.pi*N)*1e3 #Torque transmitted in Nmm\n", "D=round(((16*T)/(math.pi*tau))**(1/3),0) #Diameter of solid shaft in mm\n", "#case(b):\n", "Do=round(((T*16)/(math.pi*tau*(1-0.6**4)))**(1/3),0) #External diameter of hollow shaft in mm\n", "Di=0.6*Do #Internal diameter of hollow shaft in mm\n", "Per=(D**2-(Do**2-Di**2))/(D**2)*100 #Percentage saving in weight\n", "\n", "#Result\n", "print \"Diameter of solid shaft =\",D,\"mm\"\n", "print \"Percentage saving in weight = %.2f%%\"%Per" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Diameter of solid shaft = 122.0 mm\n", "Percentage saving in weight = 29.55%\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 16.10,page no.685" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#Given\n", "#Variable declaration\n", "P=75e3 #Power transmitted in W\n", "N=200 #R.P.M of the shaft \n", "tau=70 #Shear stress in N/sq.mm\n", "\n", "#Calculation\n", "T=P*60/(math.pi*2*N)*1e3 #Mean Torque transmitted in Nmm\n", "Tmax=1.3*T #Maximum Torque transmitted in Nmm\n", "D=round((16*Tmax/(math.pi*tau))**(1/3),0) #Suitable diameter of the shaft in mm\n", "\n", "#Result\n", "print \"Diameter of the shaft = %d mm\"%D" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Diameter of the shaft = 70 mm\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 16.11,page no.685" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#Given\n", "#Variable declaration\n", "P=300e3 #Power transmitted in W\n", "N=80 #speed of the shaft in r.p.m\n", "tau=60 #Maximum shear stress in N/sq.mm\n", "\n", "#Calculation\n", "T=P*60/(math.pi*2*N)*1e3 #Mean Torque transmitted in Nmm\n", "Tmax=1.4*T #Maximum Torque transmitted in Nmm\n", "D=round((16*Tmax/(math.pi*tau))**(1/3),0) #Suitable diameter of the shaft in mm\n", "Do=round(((Tmax*16)/(math.pi*tau*(1-0.6**4)))**(1/3),0) #External diameter of hollow shaft in mm\n", "Di=0.6*Do #Internal diameter of hollow shaft in mm\n", "\n", "#Result\n", "print \"External diameter of hollow shaft = %d mm\"%Do\n", "print \"Internal diameter of hollow shaft = %d mm\"%Di" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "External diameter of hollow shaft = 170 mm\n", "Internal diameter of hollow shaft = 102 mm\n" ] } ], "prompt_number": 7 }, { "cell_type": "code", "collapsed": false, "input": [], "language": "python", "metadata": {}, "outputs": [] } ], "metadata": {} } ] }