NEW AGE MACHINE DRAWING (THIRD EDITION) K.L. Narayana P. Kannaiah K. Venkata Reddy i NEW AGE INTERNATIONAL PUBLISHERS MACHINE DRAWING This page intentionally left blank MACHINE DRAWING • First angle projection • As per the latest BIS standards • For Degree and AM IE Third Edition Dr. K.L. Narayana Dr. P. K a nn a i ah K. Venkata Reddy a Publishing for one world NEW AGE INTERNATIONAL (P) LIMITED, PUBLISHERS Bangalore • Chennai • Cochin • Guwahati idhar • Kolkata • Lucknow • Mumbai • Ra Visit us at www.newagepublishers.com New Delhi • Bangalore • Chennai • Cochin • Guwahati • Hyderabad Jalandhar • Kolkata • Lucknow • Mumbai • Ranchi Copyright © 2006, 1999, 1994, New Age International (P) Ltd., Publishers Published by New Age International (P) Ltd., Publishers All rights reserved. No part of this ebook may be reproduced in any form, by photostat, microfilm, xerography, or any other means, or incorporated into any information retrieval system, electronic or mechanical, without the written permission of the publisher. All inquiries should be emailed to rights@newagepublishers.com ISBN (13) : 978-81-224-2518-5 Publishing for one world NEW AGE INTERNATIONAL (P) LIMITED, PUBLISHERS 4835/24, Ansari Road, Daryaganj, New Delhi - 1 10002 Visit us at www.newagepublishers.com FOREWORD I congratulate the authors Dr. P. Kannaiah, Prof. K.L. Narayana and Mr. K. Venkata Reddy of S.V.U. College of Engineering, Tirupati for bringing out this book on "Machine Drawing". This book deals with the fundamentals of Engineering Drawing to begin with and the authors introduce Machine Drawing systematically thereafter. This, in my opinion, is an excellent approach. This book is a valuable piece to the students of Mechanical Engineering at diploma, degree and AMIE levels. Dr. P. Kannaiah has a rich experience of teaching this subject for about twenty five years, and this has been well utilised to rightly reflect the treatment of the subject and the presentation of it. Prof. K.L. Narayana, as a Professor in Mechanical Engineering and Mr. K. Venkata Reddy as a Workshop Superintendent have wisely joined to give illustrations usefully from their wide experience and this unique feature is a particular fortune to this book and such opportunities perhaps might not have been available to other books. It is quite necessary for any drawing book to follow the standards of BIS. This has been done very meticulously by the authors. Besides, this book covers the syllabi of various Indian universities without any omission. Learning the draughting principles and using the same in industrial practice is essential for any student and this book acts as a valuable guide to the students of engineering. It also serves as a reference book in the design and draughting divisions in industries. This book acts almost as a complete manual in Machine Drawing. This book is a foundation to students and professionals who from here would like to learn Computer Graphics which is a must in modern days. I am confident that the students of engineering find this book extremely useful to them. Dr. MA. Veluswami Professor Machine Elements Laboratory Department of Mechanical Engineering INDIAN INSTITUTE OF TECHNOLOGY CHENNAI-600 036, INDIA This page intentionally left blank PREFACE TO THIRD EDITION The engineer, especially a mechanical engineer, needs a thorough knowledge of the working principles of any mechanism he normally deals with. To create interest and to motivate him in this direction, complete revision of the chapter on assembly drawings is done. The chapter provides individual component drawings and knowing the working mechanism of a subassembly, finally the parts are assembled. Hence, exercises/examples are included starting from simple subassemblies to moderately complex assemblies. The chapter on part drawings provides examples of assembled drawings and the student is expected to make the part drawings after imagining the shapes of them. A revision of this chapter is supposed to provide the required guidance to the knowledge seeker. The chapter on computer-aided draughting is fully revised keeping in view the present day requirements of the engineering students. The student should be trained not only to use draughting equipment but also to use a computer to produce his latest invention. It is pre- sumed that this chapter will provide him the required soft skills. The centers of excellence should revise the curriculum frequently, based on the changes needed by the academic requirements. Keeping this in view, the contents of the text are updated wherever necessary and incorporated. It is hoped that the subject content satisfies both students, teachers and paper setters. AUTHORS This page intentionally left blank PREFACE TO FIRST EDITION Drawing, as an art, is the picturisation of the imagination of the scene in its totality by an individual — the Artist. It has no standard guidelines and boundaries. Engineering drawing on the other hand is the scientific representation of an object, according to certain national and international standards of practice. It can be understood by all, with the knowledge of basic principles of drawing. Machine drawing is the indispensable communicating medium employed in industries, to furnish all the information required for the manufacture and assembly of the components of a machine. Industries are required to follow certain draughting standards as approved by International Organisation for Standards (ISO). When these are followed, drawings prepared by any one can convey the same information to all concerned, irrespective of the firm or even the country. Mechanical engineering students are required to practice the draughting standards in full, so that the students after their training, can adjust very well in industries. This book on Machine Drawing is written, following the principles of drawing, as recommended by Bureau of Indian Standards (BIS), in their standards titled "Engineering drawing practice for schools and colleges"; SP:46-1988. This is the only book on Machine Drawing, incorporating the latest standards published till now and made available to the students. Typical changes brought in the standards, in respect of names of orthographic views are listed below. These eliminate the ambiguity if any that existed earlier. The latest designations as recommended below are used throughout this book. Designation of the views as per IS:696-1972 Designations of the views as per SP:46-1988 1. Front view The view from the front 2. Top view The view from above 3. Left side view The view from the left 4. Right side view The view from the right 5. Bottom view The view from below 6. Rear view The view from the rear The contents of the book are chosen such that, the student can learn well about the drawing practice of most of the important mechanical engineering components and sub- assemblies, he studies through various courses. X Machine Drawing The principles of working, place of application and method of assembly of all the machine elements dealt with in the book will make the student thorough with the subject of mechanical engineering in general. This will also make the student understand what he is drawing instead of making the drawings mechanically. This book is intended as a text book for all mechanical engineering students, both at degree and diploma level and also students of AMIE. The contents of the book are planned, after thoroughly referring the syllabi requirements of various Indian universities and AMIE courses. The chapter on Jigs and Fixtures is intended to familiarise the students, with certain production facilities required for accurate machining/fabrication in mass production. The chapters on Limits, Tolerances and Fits and Surface Roughness are intended to correlate drawing to production. In this, sufficient stress is given to geometrical tolerances which is not found in any of the textbooks on the topic. The student, to understand production drawings, must be thorough in these topics. The chapter on Blue Print Reading has been included to train the student to read and understand complicated drawings, including production drawings. This will be of immense use to him, later in his career. Chapters on Assembly Drawings and Part Drawings are planned with a large number of exercises drawn from wide range of topics of mechanical engineering. The assemblies are selected such that they can be practiced in the available time in the class. The projects like lathe gear box and automobile gear box are developed and included in the chapter on part drawings. These are mentioned in most of the latest syllabi but not found in any of the available books on the subject. A separate chapter on Production Drawings has been included, to train the student in industrial draughting practices. These types of drawings only guide the artisan on the shop floor to the chief design engineer, in successful production of the product. We hope that this book will meet all the requirements of the students in the subject and also make the subject more interesting. Any suggestions and contribution from the teachers and other users, to improve the content of the text are most welcome. TIRUPATI August, 1994 AUTHORS CONTENTS Foreword v Preface to Third Edition vii Preface to First Edition ix Introduction 1 1.1 Graphic Language 1 1.1.1 General 1 1.1.2 Importance of Graphic Language 1 1.1.3 Need for C...
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