3rd Edition
Fundamentals of Machine Elements SI Version
New and Improved SI Edition—Uses SI Units Exclusively in the Text
Adapting to the changing nature of the engineering profession, this third edition of Fundamentals of Machine Elements aggressively delves into the fundamentals and design of machine elements with an SI version. This latest edition includes a plethora of pedagogy, providing a greater understanding of theory and design.
Significantly Enhanced and Fully Illustrated
The material has been organized to aid students of all levels in design synthesis and analysis approaches, to provide guidance through design procedures for synthesis issues, and to expose readers to a wide variety of machine elements. Each chapter contains a quote and photograph related to the chapter as well as case studies, examples, design procedures, an abstract, list of symbols and subscripts, recommended readings, a summary of equations, and end-of-chapter problems.
What’s New in the Third Edition:
- Covers life cycle engineering
- Provides a description of the hardness and common hardness tests
- Offers an inclusion of flat groove stress concentration factors
- Adds the staircase method for determining endurance limits and includes Haigh diagrams to show the effects of mean stress
- Discusses typical surface finishes in machine elements and manufacturing processes used to produce them
- Presents a new treatment of spline, pin, and retaining ring design, and a new section on the design of shaft couplings
- Reflects the latest International Standards Organization standards
- Simplifies the geometry factors for bevel gears
- Includes a design synthesis approach for worm gears
- Expands the discussion of fasteners and welds
- Discusses the importance of the heat affected zone for weld quality
- Describes the classes of welds and their analysis methods
- Considers gas springs and wave springs
- Contains the latest standards and manufacturer’s recommendations on belt design, chains, and wire ropes
The text also expands the appendices to include a wide variety of material properties, geometry factors for fracture analysis, and new summaries of beam deflection.
Part I — Fundamentals
Introduction
What is Design?
Design of Mechanical Systems
Design as a Multidisciplinary Endeavor
Design of Machine Elements
Computers in Design
Catalogs and Vendors
Units
Unit Checks
Significant Figures
Summary
Load, Stress, and Strain
Introduction
Critical Section
Load Classification and Sign Convention
Support Reactions
Static Equilibrium
Free-Body Diagram
Supported Beams
Shear and Moment Diagrams
Stress
Stress Element
Stress Tensor
Plane Stress
Mohr’s Circle
Three-Dimensional Stresses
Octahedral Stresses
Strain
Strain Tensor
Plane Strain
Summary
Introduction to Materials and Manufacturing
Introduction
Ductile and Brittle Materials
Classification of Solid Materials
Stress-Strain Diagrams
Properties of Solid Materials
Stress-Strain Relationships
Two-Parameter Materials Charts
Effects of Manufacturing
Summary
Stresses and Strains
Introduction
Properties of Beam Cross Sections
Normal Stress and Strain
Torsion
Bending Stress and Strain
Transverse Shear Stress and Strain
Summary
Deformation
Introduction
Moment-Curvature Relation
Singularity Functions
Method of Superposition
Strain Energy
Castigliano’s Theorem
Summary
Failure Prediction for Static Loading
Introduction
Stress Concentration
Fracture Mechanics
Modes of Crack Growth
Fracture Toughness
Failure Prediction for Uniaxial Stress State
Failure Prediction for Multiaxial Stress State
Summary
Fatigue and Impact
Introduction
Fatigue
Cyclic Stresses
Strain Life Theory of Fatigue
Fatigue Strength
Fatigue Regimes
Stress Concentration Effects
The Modified Endurance Limit
Cumulative Damage
Influence of Nonzero Mean Stress
Influence of Multi-Axial Stress States
Fracture Mechanics Approach to Fatigue
Linear Impact Stresses and Deformations
Summary
Lubrication, Friction, and Wear
Introduction
Surface Parameters
Conformal and Nonconformal Surfaces
Hertzian Contact
Bearing Materials
Lubricant Rheology
Regimes of Lubrication
Friction
Wear
Summary
Part II — Machine Elements
Columns
Introduction
Equilibrium Regimes
Concentrically Loaded Columns
End Conditions
Euler’s Buckling Criterion
Johnson’s Buckling Criterion
AISC Criteria
Eccentrically Loaded Columns
Summary
Stresses and Deformations in Cylinders
Introduction
Tolerances and Fits
Pressurization Effects
Rotational Effects
Press Fits
Shrink Fits
Summary
Shafting and Associated Parts
Introduction
Design of Shafts for Static Loading
Fatigue Design of Shafts
Additional Shaft Design Considerations
Critical Speed of Rotating Shafts
Keys, Roll Pins, Splines and Set Screws
Retaining Rings and Pins
Flywheels
Couplings
Summary
Hydrodynamic and Hydrostatic Bearings
Introduction
The Reynolds Equation
Thrust Slider Bearings
Journal Slider Bearings
Squeeze Film Bearings
Hydrostatic Bearings
Summary
Rolling-Element Bearings
Introduction
Historical Overview
Bearing Types and Selection
Geometry
Kinematics
Separators
Static Load Distribution
Elastohydrodynamic Lubrication
Fatigue Life
Variable Loading
Summary
General Gear Theory; Spur Gears
Introduction
Types of Gears
Gear Geometry
Gear Ratio
Contact Ratio and Gear Velocity
Tooth Thickness and Backlash
Gear Trains
Gear Manufacture and Quality
Gear Materials
Loads Acting on a Gear Tooth
Bending Stresses in Gear Teeth
Contact Stresses in Gear Teeth
Elastohydrodynamic Film Thickness
Gear Design Synthesis
Summary
Helical, Bevel, and Worm Gears
Introduction
Helical Gears
Bevel Gears
Worm Gears
Summary
Fasteners, Connections, and Power Screws
Introduction
Thread Terminology, Classification, and Designation
Power Screws
Threaded Fasteners
Riveted Fasteners
Welded, Brazed, and Soldered Joints
Adhesive Bonding
Integrated Snap Fasteners
Summary
Springs
Introduction
Spring Materials
Helical Compression Springs
Helical Extension Springs
Helical Torsion Springs
Leaf Springs
Gas Springs
Belleville Springs
Wave Springs
Summary
Brakes and Clutches
Introduction
Thermal Considerations
Thrust Pad Clutches and Brakes
Cone Clutches and Brakes
Block or Short-Shoe Brakes
Long-Shoe, Internal, Expanding Rim Brakes
Long-Shoe, External, Contracting Rim Brakes
Symmetrically Loaded Pivot-Shoe Brakes
Band Brakes
Slip Clutches
Summary
Flexible Machine Elements
Introduction
Flat Belts
Synchronous Belts
V-Belts
Wire Ropes
Rolling Chains
Summary
Appendices
Index
Biography
Steven R. Schmid received his B.S. in mechanical engineering from the Illinois Institute of Technology in 1986. He earned his master’s degree from Northwestern University in 1989 and his Ph.D. in 1993, both in mechanical engineering. In 1993 he joined the faculty at the University of Notre Dame, where he is a professor of aerospace and mechanical engineering, teaching and conducting research in design and manufacturing. Dr. Schmid holds professional engineering (P.E.) and certified manufacturing engineer (C.Mfg.E.) licenses. He was awarded the ASME Foundation Swanson Fellowship in 2012, and is a Fellow of the American Society of Mechanical Engineers.
Bernard J. Hamrock
joined the staff of Ohio State University as a professor of mechanical engineering in 1985 and is now professor emeritus. Before joining Ohio State University he spent 18 years as a research consultant in the Tribology Branch of the NASA Lewis Research Center in Cleveland, Ohio. He received his Ph.D. and doctor of engineering degrees from the University of Leeds, England. His research has resulted in a book, three separate chapters for handbooks, and over 150 archival publications. He has received several awards including the 2000 Mayo D. Hersey Award from the American Society of Mechanical Engineers.Bo O. Jacobson
received his Ph.D. and D.Sc. degrees from Lund University in Sweden. From 1973 until 1987 he was professor of machine elements at Luleå University of Technology in Sweden. In 1987 he joined SKF Engineering & Research Centre in the Netherlands, while retaining a professorship at Chalmers University from 1987 to 1991 and at Luleå University of Technology from 1992 to 1997. In 1997 he was appointed professor of machine elements at Lund University, Sweden. He has published four compendia used at Swedish universities, and has contributed more than 100 archival publications. His awards include the Tribology Gold Medal received in 1997.