Design of Machine Elements

by Spotts, Merhyle F.; Shoup, Terry E.; Hornberger, Lee E.

• ISBN13: 9780130489890
• ISBN10: 0130489891
• Edition: 8th
• Format: Hardcover
• Copyright: 2003-10-14
• Publisher: Pearson

Summary

Now considered a classic in its field, this book provides a comprehensive survey of machine elements and analytical design methods.This book covers the tools and techniques necessary to facilitate design calculations for the most frequently encountered mechanical elements.For professionals in the field of Machine Design who need a comprehensive reference on the subject.

Table of Contents

PREFACE	xv
INTRODUCTION	1	(14)
I-1 Problem Solving and Design	1	(2)
I-2 The Design Process	3	(2)
I-3 Stages of Design	5	(2)
I-4 Finding and Using Information in Machine Design	7	(2)
I-5 Recognized Standards for Design	9	(2)
I-6 Computational Tools for Machine Design	11	(3)
I-7 Conclusions	14	(1)
References	14	(1)
CHAPTER 1 FUNDAMENTAL PRINCIPLES	15	(104)
1-1 Statical Equilibrium	17	(1)
1-2 Engineering Materials	17	(1)
1-3 Tension and Compression Stress	18	(2)
1-4 Tension and Compression in SI Units	20	(2)
1-5 Force and Mass	22	(1)
1-6 Statically Indeterminate Problems in Tension and Compression	23	(2)
1-7 Center of Gravity	25	(2)
1-8 Bending of Beams	27	(3)
1-9 Moment of Inertia	30	(3)
1-10 Transfer Axis for Moment of Inertia	33	(2)
1-11 Principle of Superposition	35	(3)
1-12 Additional Beam Equations	38	(1)
1-13 Deflection of Beams	39	(7)
1-14 Effect of Ribs on Castings	46	(2)
1-15 Shearing Stress	48	(1)
1-16 Transverse Shearing Stress in Beams	49	(6)
1-17 Shear and Bending Moment Diagrams	55	(3)
1-18 Slender Compression Members or Columns	58	(4)
1-19 Stresses in Any Given Direction	62	(2)
1-20 The Mohr Circle	64	(4)
1-21 Stress Manipulation in Three Dimensions	68	(8)
1-22 Stresses and Deformations in Two Directions	76	(1)
1-23 Deflection of A Beam from Shearing Stress	77	(2)
1-24 Principle of St. Venant	79	(1)
References	80	(1)
Problems	80	(39)
CHAPTER 2 WORKING STRESSES AND FAILURE THEORIES	119	(66)
2-1 Failure and Phenomenological Failure Theories	120	(3)
2-2 Stress-Strain Diagrams	123	(3)
2-3 Phenomenological Failure Theories Based on Stress	126	(11)
2-4 Stress Concentration Caused by Sudden Change in Form	137	(14)
2-5 Design for Cyclic Loading	151	(17)
2-6 Conclusion	168	(1)
References	169	(1)
Problems	170	(15)
CHAPTER 3 DESIGN OF SHAFTS	185	(76)
3-1 Torsion of Circular Shaft	187	(7)
3-2 Power Transmitted	194	(3)
3-3 Maximum Static Shearing Stress	197	(1)
3-4 Design of Shafts for Fluctuating Loads	198	(6)
3-5 Keys	204	(4)
3-6 Stress Concentration	208	(2)
3-7 Couplings	210	(3)
3-8 Bending Loads in Two Planes	213	(1)
3-9 Shaft on Three Supports	213	(4)
3-10 Crankshafts	217	(3)
3-11 Critical Speed of a Rotating Shaft	220	(1)
3-12 Deflection of Shaft of Nonuniform Diameter	221	(3)
3-13 Slope of Shaft by Elastic Energy	224	(1)
3-14 Torsion of Noncircular Shafts	225	(1)
3-15 Torsion of a Wide Rectangular Bar	226	(2)
3-16 Torsion of Rectangular Bars-General Case	228	(2)
3-17 Composite Sections	230	(3)
3-18 Thin-Walled Tube	233	(2)
3-19 Materials Used for Shafting	235	(1)
References	236	(1)
Problems	237	(24)
CHAPTER 4 SPRINGS	261	(55)
4-1 Helical Springs	263	(5)
4-2 Properties of Spring Materials	268	(2)
4-3 Hot-Formed Springs	270	(1)
4-4 Helical Spring of Minimum Volume of Material-Static Load	271	(4)
4-5 Optimum Design of Helical Spring	275	(5)
4-6 Fatigue of Springs	280	(1)
4-7 Design for Fluctuating Loads	281	(3)
4-8 Buckling of Compression Springs	284	(1)
4-9 Vibration or Surging of Helical Springs	284	(1)
4-10 Commercial Tolerances	285	(2)
4-11 Effect of End Turns for Compression Springs	287	(1)
4-12 Helical Extension Springs	288	(1)
4-13 Helical Springs of Rectangular Wire	289	(2)
4-14 Helical Springs with Torsional Loading	291	(3)
4-15 Leaf Springs	294	(4)
4-16 Energy Storage by Springs	298	(1)
4-17 Belleville Spring	299	(2)
4-18 Rubber Springs	301	(7)
References	308	(1)
Problems	308	(8)
CHAPTER 5 SCREWS	316	(38)
5-1 Kinds of Threads	316	(3)
5-2 Standardized Threads	319	(2)
5-3 Unified Threads	321	(1)
5-4 American National Threads	322	(1)
5-5 Identification Symbols	323	(1)
5-6 SI Threads	323	(2)
5-7 Effect of Initial Stress	325	(4)
5-8 Additional Design Considerations	329	(2)
5-9 Power Screws	331	(8)
5-10 Torque Required to Produce Desired Clamping Force	339	(2)
5-11 Friction of Screws	341	(1)
5-12 Stress Concentration	341	(2)
5-13 Locknuts	343	(1)
5-14 Materials and Methods of Manufacture	344	(1)
5-15 Stress Due to Impact Load	345	(3)
5-16 Relaxation	348	(1)
References	348	(1)
Problems	348	(6)
CHAPTER 6 BELTS, CLUTCHES, BRAKES AND CHAINS	354	(54)
6-1 V-belts	355	(2)
6-2 Center Distance for V-belt Drive	357	(4)
6-3 Design of V-belts	361	(2)
6-4 Other Types of Belts	363	(2)
6-5 Disk or Plate Clutch	365	(4)
6-6 Disk Brakes	369	(1)
6-7 Cone Clutch	370	(1)
6-8 Band Brake	371	(4)
6-9 Block Brake with Short Shoe	375	(1)
6-10 Pivoted Block Brake with Long Shoe	376	(9)
6-11 Brake with Pivoted Symmetrical Shoe	385	(1)
6-12 Lining Pressures	386	(1)
6-13 Heating of Brakes	387	(1)
6-14 Roller Chains	388	(1)
6-15 Design Capacity of Roller Chains	389	(4)
6-16 Galling of Roller Chains	393	(1)
6-17 Polygonal Action	394	(1)
6-18 Silent Chain	395	(1)
References	396	(1)
Problems	396	(12)
CHAPTER 7 WELDED AND RIVETED CONNECTIONS	408	(48)
7-1 Fabrication by Welding	409	(1)
7-2 Fusion Welding	410	(1)
7-3 Strength of Fusion Welds	411	(2)
7-4 Eccentrically Loaded Welds-Static Loads	413	(7)
7-5 Stress Concentration in Welds	420	(1)
7-6 Residual Stress-Weldability	421	(2)
7-7 Welding Electrodes	423	(1)
7-8 Design for Fluctuating Loads	424	(2)
7-9 Resistance Welding	426	(1)
7-10 Other Kinds of Welding	427	(2)
7-11 Soldering and Brazing	429	(2)
7-12 Furnace Brazing	431	(1)
7-13 Riveted Joint with Central Load	432	(1)
7-14 Stresses in Rivets	433	(1)
7-15 Stresses in a Cylindrical Shell	433	(4)
7-16 Riveted Joint with Eccentric Load	437	(5)
7-17 Instantaneous Center of Rotation	442	(1)
7-18 Adhesives	442	(2)
References	444	(1)
Problems	445	(11)
CHAPTER 8 LUBRICATION	456	(50)
8-1 Viscosity and Newton's Law	458	(8)
8-2 Petroff's Bearing Equation	466	(4)
8-3 Load-Carrying Journal Bearing	470	(1)
8-4 Load and Friction Curves for Journal Bearings	471	(7)
8-5 Power Lost in Friction	478	(1)
8-6 Power Lost by Self-Cooled Bearings	479	(5)
8-7 Designing for Film Temperature and Minimum Film Thickness	484	(2)
8-8 Viscosity Index	486	(1)
8-9 The Zn/ P Curve	487	(3)
8-10 Bearing Materials	490	(3)
8-11 Bearing Loads	493	(1)
8-12 Construction of Bearings	494	(1)
8-13 Clearance and Oil Grooves	495	(2)
8-14 Elastic Matching	497	(1)
8-15 Dry Friction	498	(1)
8-16 Boundary or Thin-Film Lubrication	499	(1)
8-17 Mixed or Semifluid Lubrication	500	(1)
References	500	(1)
Problems	501	(5)
CHAPTER 9 BALL AND ROLLER BEARINGS	506	(37)
9-1 Construction and Types of Ball Bearings	506	(2)
9-2 Selection of Ball Bearings	508	(4)
9-3 Effect of Axial Load	512	(3)
9-4 Design for Variable Loading	515	(4)
9-5 Static Capacity	519	(1)
9-6 Design for Different Confidence Levels	520	(1)
9-7 Friction and Lubrication of Ball Bearings	520	(1)
9-8 Bearing Materials and Surface Finish	521	(1)
9-9 Mounting of Ball Bearings	522	(2)
9-10 Permissible Misalignment	524	(1)
9-11 Unground Ball Bearings	525	(1)
9-12 Relative Advantages of Rolling Element Bearings	525	(1)
9-13 Roller Bearings	526	(2)
9-14 Contact Stress between Spheres and Cylinders	528	(9)
9-15 Elasto-hydrodynamic Lubrication	537	(1)
References	537	(1)
Problems	538	(5)
CHAPTER 10 SPUR GEARS	543	(83)
10-1 Introduction	545	(1)
10-2 Velocity Law of Toothed Gearing	546	(2)
10-3 Kinematics of Involute Gear Teeth	548	(2)
10-4 Cycloidal Gear Teeth	550	(1)
10-5 Pitches of Gear Teeth	551	(3)
10-6 Gear Pitches in SI Units	554	(3)
10-7 Standard Systems of Gearing	557	(2)
10-8 Methods of Manufacture	559	(3)
10-9 Backlash	562	(2)
10-10 Gear Finishing Methods	564	(1)
10-11 Load on Gear Tooth from Power Transmitted	564	(3)
10-12 Determination of Bearing Loads	567	(2)
10-13 Contact Ratio	569	(2)
10-14 Undercutting in Gear Teeth	571	(2)
10-15 Long and Short Addendum Gearing	573	(3)
10-16 Speed Ratios of Gear Trains	576	(4)
10-17 Internal or Annular Gears	580	(1)
10-18 Dimensioning of Gears	581	(1)
10-19 Materials for Gears	581	(1)
10-20 Lubrication and Mounting of Gears	582	(1)
10-21 Planetary Gear Trains	583	(2)
10-22 Design of Gears to Prevent Failures	585	(32)
References	617	(1)
Problems	618	(8)
CHAPTER 11 HELICAL, BEVEL, AND WORM GEARS	626	(58)
11-1 Helical Gears	627	(3)
11-2 The Geometry of Helical Gears	630	(2)
11-3 Virtual Number of Teeth	632	(1)
11-4 Center Distance of Mating Gears	632	(3)
11-5 Contact Ratios for Helical Gears	635	(1)
11-6 Tooth Loads of Helical Gears	635	(1)
11-7 Design of Parallel Shaft Helical Gears to Prevent Failures	636	(15)
11-8 Bevel Gears	651	(2)
11-9 The Geometry of Bevel Gears	653	(1)
11-10 Loads on Bevel Gears	654	(1)
11-11 Design of Bevel Gears to Prevent Failures	655	(11)
11-12 Worm Gears	666	(2)
11-13 Geometric Relationships of Worm Gears	668	(8)
11-14 Forces in Worm Gear Sets	676	(1)
11-15 Design of Worm Gear Sets	676	(5)
References	681	(1)
Problems	681	(3)
CHAPTER 12 MISCELLANEOUS MACHINE ELEMENTS	684	(79)
12-1 Stresses in a Thick Cylinder	684	(5)
12-2 Shrink and Press Fit Stresses	689	(4)
12-3 Stress Concentration Caused by Press Fit	693	(5)
12-4 Stresses in Disk Flywheel	698	(2)
12-5 Flywheel with Spokes and Rim	700	(4)
12-6 Flywheel Requirements	704	(3)
12-7 Impact of Elastic Bodies	707	(2)
12-8 Impact Stresses by Energy Method	709	(6)
12-9 Force Produced by Falling Weight	715	(2)
12-10 Impact of Weight on Beam	717	(1)
12-11 Gaskets and Seals	718	(2)
12-12 Design of Gaskets for Static Loads	720	(4)
12-13 Wire Rope	724	(5)
12-14 Curved Beams	729	(3)
12-15 Curved Beam of Rectangular Cross Section	732	(5)
12-16 Curved Beam of Circular Cross Section	737	(1)
12-17 Angular Deflection of Curved Bar	737	(1)
12-18 Cams	737	(3)
12-19 Plate Cam with Central Roller Follower	740	(2)
12-20 Manufacture of Cam with Central Roller Follower	742	(2)
12-21 Plate Cam with Flat-Faced Follower	744	(2)
12-22 Polydyne Cam	746	(1)
12-23 Remarks on Cam Design	746	(1)
12-24 Snap Rings	747	(1)
12-25 Flat Plates	748	(4)
References	752	(1)
Problems	753	(10)
CHAPTER 13 PRINCIPLES OF FORM SYNTHESIS	763	(17)
13-1 A Review of Stress Patterns in Machine Parts	763	(4)
13-2 The Principles of Form Synthesis	767	(2)
13-3 Exceptions to the Form Synthesis Principles	769	(1)
13-4 Design of Joints	770	(7)
13-5 Conclusions	777	(1)
References	778	(1)
Problems	778	(2)
CHAPTER 14 ENGINEERING MATERIALS	780	(57)
14-1 The Tension Test	780	(3)
14-2 Physical Constitution of Steel	783	(2)
14-3 Types of Steel Used in Machine Construction	785	(1)
14-4 Numbering Systems for Carbon and Alloy Steels	786	(3)
14-5 Plain Carbon Steel	789	(4)
14-6 Alloy Steels	793	(5)
14-7 High-Strength Low-Alloy Steels, HSLA	798	(1)
14-8 Cost of Steel	798	(1)
14-9 Heat Treatment of Steel	799	(3)
14-10 Residual Stresses from Heat Treatment	802	(1)
14-11 Carburizing and Nitrilling	803	(1)
14-12 Flame Hardening	804	(2)
14-13 Strain Hardening	806	(1)
14-14 Hardness	807	(2)
14-15 Machinability	809	(1)
14-16 Grain Size	809	(1)
14-17 Corrosion	810	(1)
14-18 Prevention of Corrosion	811	(1)
14-19 Stainless Steel	812	(1)
14-20 Wear	813	(3)
14-21 Short-Term Effects of High Temperatures	816	(1)
14-22 Creep of Steel at High Temperature	817	(2)
14-23 Cast Iron	819	(3)
14-24 Malleable Iron/Nodular Iron	822	(1)
14-25 Cast Steel	822	(2)
14-26 Tool Steel	824	(1)
14-27 Aluminum Alloys	825	(1)
14-28 Alloy and Temper Designations	826	(1)
14-29 Composition and Mechanical Properties	827	(1)
14-30 Magnesium Alloys	827	(3)
14-31Copper Alloys	830	(3)
14-32 Alloys for Die Castings	833	(3)
References	836	(1)
CHAPTER 15 DESIGNING WITH PLASTIC MATERIALS	837	(23)
15-1 Introduction	837	(4)
15-2 The Basics: The Chemistry and Physics of Plastics	841	(1)
15-3 Characteristics of Thermoplastic Materials	842	(2)
15-4 Amorphous vs. Semicrystalline Thermoplastics	844	(3)
15-5 Characteristics of Thermoset Materials	847	(3)
15-6 Designing with Plastics	850	(1)
15-7 Creep in Plastics	850	(5)
15-8 Environmental Properties of Plastics	855	(1)
15-9 Safety Factors	856	(1)
15-10 Additives for Plastics	856	(1)
15-11 Recycling of Plastics	857	(1)
15-12 Plastics Resources	857	(1)
References	857	(1)
Problems	858	(2)
APPENDIX MODULES	860	(54)
INDEX	914

Excerpts

We are pleased to publish this eighth edition of a text that has become a classic among the machine design community. This new edition contains a number of important improvements over the previous edition.The example problems have been reformatted using a structured approach. This addition should make the logic of the example problems much easier to follow, and the authors recommend that the student of machine design adopt this structured approach in their work.Most of the spreadsheet modules found in the previous edition have been upgraded and improved. In many cases the use of "drop-down menus" allows the user to switch between unit systems without the need to switch to a different module. Additionally, the spreadsheet modules now include command buttons to allow the user to view additional information of importance to their application. In one of the spreadsheets, the user can produce a scaled plot of the Mohr's Circle for a given state of two-dimensional stress. Some completely new spreadsheet modules have been added to allow a greater range of problems to be solved.Perhaps one of the most important new features of this edition is the inclusion of a chapter on design with plastic materials. This chapter, written by L. E. Hornberger, a world-class leader in plastics design and recycling, provides an excellent overview of how plastic materials are having a strong positive influence on the design of machine elements. This new edition represents over 80 years of experience of its three authors in industry and in the classroom. As with any "work in process," we continue to welcome your helpful suggestions for improvement of this text.As with any project of this magnitude, there are many people to thank for their suggestions, contributions, and helpful ideas. In particular we thank William L. Cleghorn, University of Toronto; Harvey Hoy, University of Wisconsin; Richard A. Hultin, Rochester Institute of Technology; Ronald L. Prielie, University of North Carolina Charlotte; and Tom Overman, Santa Clara University. T. E. SHOUP L. E. HORNBERGER Santa Clara University