{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Chapter 19: Drawing of Rods, Wires and Tubes"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Example 19.1, Analysis of Wiredrawing, Page No. 640"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "\n",
      "Drawing Stress = 240.422 MPa\n",
      "Drawing Force = 12.0849 kN\n",
      "Power = 36.2548 kW\n",
      "Horsepower = 48.599 hp\n"
     ]
    }
   ],
   "source": [
    "from math import pi\n",
    "from math import radians\n",
    "from math import tan\n",
    "from math import log\n",
    "\n",
    "#variable declaration\n",
    "def cot(x):\n",
    "    return 1/tan(x);\n",
    "Ab=10;\n",
    "r=0.2;\n",
    "alpha=12;\n",
    "mu=0.09;\n",
    "n=0.3;\n",
    "K=1300;\n",
    "v=3;\n",
    "\n",
    "#calculation\n",
    "alpha=radians(alpha);\n",
    "B=mu*cot(alpha/2);\n",
    "e1=log(1/(1-r));\n",
    "sigma=K*e1**0.3/(n+1);\n",
    "Aa=Ab*(1-r);\n",
    "sigma_xa=sigma*((1+B)/B)*(1-(Aa/Ab)**B);\n",
    "Aa=pi*Aa**2/4;\n",
    "Pd=sigma_xa*Aa;\n",
    "Pd=Pd/1000;                        #conversion to kilo units\n",
    "P=Pd*v;\n",
    "H=P/0.746;\n",
    "\n",
    "#result\n",
    "print('\\nDrawing Stress = %g MPa\\nDrawing Force = %g kN\\nPower = %g kW\\nHorsepower = %g hp')%(sigma_xa,Pd,P,H);"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Example 19.2, Analysis of Wiredrawing, Page No. 645"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "\n",
      "By First Approximation, r = 0.514412\n",
      "By Second Approximation, r = 0.830601\n"
     ]
    }
   ],
   "source": [
    "from math import radians\n",
    "from math import tan\n",
    "from math import log\n",
    "\n",
    "#variable declaration\n",
    "def cot(x):\n",
    "    return 1/tan(x);\n",
    "alpha=12;\n",
    "r=0.2;\n",
    "mu=0.09;\n",
    "n=0.3;\n",
    "K=1300;\n",
    "v=3;\n",
    "\n",
    "#calculation\n",
    "alpha=radians(alpha);\n",
    "B=mu*cot(alpha/2);\n",
    "e1=log(1/(1-r));\n",
    "sigma_xa=K*e1**0.3/(n+1);\n",
    "r1=1-((1-(B/(B+1)))**(1/B));\n",
    "e=log(1/(1-r1));\n",
    "sigma0=1300*e**0.3;\n",
    "r2=1-(1-((sigma0/sigma_xa)*(B/(B+1)))**(1/B));\n",
    "\n",
    "#result\n",
    "print('\\nBy First Approximation, r = %g\\nBy Second Approximation, r = %g')%(r1,r2);"
   ]
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python 2",
   "language": "python",
   "name": "python2"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 2
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython2",
   "version": "2.7.9"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 0
}