00296nam a22000977a 4500100002100000100001100021245008500032260002900117300001000146700004200156  aMuhammad Zaheer   a07ME21  aCase Study of Piping System Design and its Maintenance in National Refinery Ltd.  aNawabshah:bQUEST,c2007  a105p.  aDepartment of Mechanical Engineering