Table of Contents

Foreword, Preface
Gear-Design Trends
Manufacturing Trends
Small, Low-Cost Gears for Toys, Gadgets and Mechanisms Appliance Gears Machine Tools Control Gears Vehicle Gears Transportation Gears Marine Gears Aerospace Gears Industrial Gearing Gears in the Oil and Gas Industry Mill Gears
Selection of the Right Kind of Gear
External Spur Gears External Helical Gears Internal Gears Straight Bevel Gears Zerol Bevel Gears Spiral Bevel Gears Hypoid Gears Face Gears Crossed-Helical Gears (Nonenveloping Worm Gears) Single-Enveloping Worm Gears Double-Enveloping Worm Gears Spiroid Gears
Preliminary Design Considerations
Stress Formulas
Calculated Stresses Gear-Design Limits Gear-Strength Calculations Gear Surface-Durability Calculations Gear Scoring Thermal Limits
Preliminary Estimate of Gear Size
Gear Specifications Size of Spur and Helical Gears by Q-Factor Method Indexes of Tooth Loading Estimating Spur- and Helical-Gear Size by K-Factor Estimating Bevel-Gear Size Estimating Worm-Gear Size Estimating Spiroid-Gear Size
Data Needed for Gear Drawings
Gear Dimensional Data Gear-Tooth Tolerances Gear Material and Heat Treat Data Enclosed Gear Unit Requirements
Design Formulas
Calculations of Gear-Tooth Data
Number of Pinion Teeth Hunting Teeth Spur-Gear-Tooth Proportions Root Filler Radii of Curvature Long-Addendum Pinions Tooth Thickness Chordal Dimensions Degrees Roll and Limit Diameter Form Diameter and Contact Ratio Spur-Gear Dimension Sheet Internal-Gear Dimension Sheet Helical-Gear Tooth Proportions Helical-Gear Dimension Sheet Bevel-Gear Tooth Proportions Straight-Bevel-Gear Dimension Sheet Spiral-Bevel-Gear Dimension Sheet Zerol-Bevel-Gear Dimension Sheet Hypoid-Gear Calculations Face Gear Calculations Crossed-Helical-Gear Proportions Single-Enveloping-Worm-Gear Proportions Single-Enveloping Worm Gears Double-Enveloping Worm Gears
Gear-Rating Practice
General Considerations in Rating Calculations General Formulas for Tooth Bending Strength and Tooth Surface Durability Geometry Factors for Strength Overall Derating Factor for Strength Geometry Factors for Durability Overall Derating Factor for Surface Durability Load Rating of Worm Gearing Design Formulas for Scoring Trade Standards for Rating Gears Vehicle Gear-Rating Practice Marine Gear-Rating Practices Aerospace Gear-Rating Practices
Gear Materials
Steels for Gears
Mechanical Properties Heat-Treating Techniques Heat-Treating Data Hardness Tests
Localized Hardening of Gear Teeth
Carburizing Nitriding Induction Hardening of Steel Flame Hardening of Steel Combined Heat Treatments Metallurgical Quality of Steel Gears
Cast Irons for Gears
Gray Cast Iron Ductile Iron Sintered Iron
Nonferrous Gear Metals
Kinds of Bronze Standard Gear Bronzes
Nonmetallic Gears
Thermosetting Laminates Nylon Gears
Gear-Manufacturing Methods
Gear-Tooth Cutting
Gear Hobbing Shaping-Pinion Cutter Shaping-Rack Cutter Cutting Bevel Gears Gear Milling Broaching Gears Punching Gears G-TRAC Generating
Gear Grinding
Form Grinding Generating Grinding-Disc Wheel Generating Grinding-Bevel Gears Generating Grinding-Threaded Wheel Thread Grinding
Gear Shaving, Rolling, and Honing
Rotary Shaving Rack Shaving Gear Rolling Gear Honing
Gear Measurement
Gear Accuracy Measurements Machines to Measure Gears
Gear Casting and Forming
Cast and Molded Gears Sintered Gears Cold-Drawn Gears and Rolled Worm Threads
Design of Tools to Make Gear Teeth
Shaper Cutters Gear Hobs Spur-Gear Milling Cutters Worm Milling Cutters and Grinding Wheels Gear-Shaving Cutters Punching Tools Sintering Tools
The Kinds and Causes of Gear Failures
Analysis of Gear-System Problems
Determining the Problem Possible Causes of Gear-System Failures Incompatibility of Gear Systems Investigation of Gear Systems
Analysis of Tooth Failures and Gear Bearing Failures
Nomenclature of Gear Failure Tooth Breakage Pitting of Gear Teeth Scoring Failures Wear Failures Gearbox Bearings Rolling-Element Bearings Sliding-Element Bearings
Some Causes of Gear Failure Other than Excess Transmitted Load
Overload Gear Failures Gear Casing Problems Lubrication Failures Thermal Problems in Fast-Running Gears
Special Design Problems
Center Distance Problems Profile Modification Problems Load Rating Problem
Appendix Material
Introduction to Gears Dynamic Load Theory Highest and Lowest Points of Single-Tooth Contact Layout of Large Circles by Calculation Special Calculations for Spur Gears Special Calculation for Internal Gears Special Calculation for Helical Gears Summary Sheets for Bevel Gears Complete AGMA and ISO Formulas for Bending Strength and Surface Durability Profile Modification Calculation Procedure The Basics of Gear-Tooth Measurement for Accuracy and Size Shaper-Cutter Tooth Thickness General Method for Determining Tooth Thicknesses when Helical Gears Are Operated on Spread Centers Calculation of Geometry Factor for Scoring

References, Index
186 tables, 291 figures
HUNDREDS OF ILLUSTRATIONS
Almost 300 diagrams and other schematics, photographs and micrographs clearly illustrate gear designs, gearsets and assemblies, and applications. Here is a small sampling of these illustrations.
Tractor power train Partially assembled double-reduction marine gear unit Two-stage epicyclic gear, close-coupled to a high-speed gas turbine Spur-gear and rack terminology Helical-gear and rack terminology Internal gear terminology Hypoid-gear arrangement Terminology of cone-drive worm gears Dimensions used in scoring-factor calculation Eight kinds of gear arrangements for spur or helical gears Standard drawing format for spiral bevel gears Calculation of bevel-gear body dimensions Worm-gear design examples Machine induction-hardening of large internal gear Metallurgical examples, nitrided gears (micrographs) Phenolic laminated gear with a steel hub . . . Comparison of form grinding and generating grinding Operating principles of single-die gear-rolling machine Outline of methods for making gear teeth
ALMOST 200 TABLES
A wealth of data is economically provided in the many tables in this text. Here is a small sampling of this reference material.
Gear Terms, Symbols and Units Scoring Calculation Methods Ratio Factors for Single-Reduction Gears Nominal Capacity of Double-Enveloping Worm Gearing Typical AGMA Gear Tolerances for Quality Numbers 9-13 Spur-Gear Proportions Tolerances on Tooth Thickness Spur-Gear Dimensions Helical-Gear Basic Tooth Data Indexes of Tooth Loading for Preliminary Design Calculations Straight-Bevel-Gear Dimensions Load-Stress Factors for Crossed-Helical Gears Nominal Lubricant Properties Composition of Typical Gear Steels Hardness-Testing Apparatus and Applications for Gears Some Examples of Production Time for Hobbing or Milling Gear Teeth Checklist (for) Investigating Gear Failures

Reviews

This major work . . . should become the bible of the industry, and its guidelines will serve the engineering body responsible for present and future standards of gearing. . . . Recognized nationally and internationally as one of the foremost contributors to the advancement of gear design, Mr. Dudley . . . received the E. P. Connell Award, which is the highest honor of the American Gear Manufacturers Association.
—William W. Ingraham, Executive Director, American Gear Manufacturers Association

"…the only and the most comprehensive and updated reference source book available in the meantime for gear practitioners. … of practical interest for both for gear practitioners as well as for gear theoreticians. ... recommended for university students, both graduate and postgraduate."
—Prof. Joseph A. Bukhbinder