The SMI Handbook
of Spring Design

Developed and published under the guidance of the SMI Technology Committee, the SMI Handbook of Spring Design is a guide for spring engineers and spring users in designing and specifying the most widely applied types of springs. Design methods for each type are described, and examples of calculations are given for most. Suggested specification forms are presented for the three most common spring types: compression, extension and torsion. Includes both metric and U.S. units of measure.

A handy 100-page reference, the Handbook is the perfect tool to keep in a briefcase or at a workstation. It also makes a useful, educational customer gift. A composite of information from the more extensive four-volume Encyclopedia of Spring Design, the Handbook concentrates on the most important elements of spring design and provides answers to the most frequently asked questions. (Scroll down for the complete Table of Contents.)

Among SMI's most popular publications over the years, the Handbook was most recently revised and updated in 2002.

Each Handbook has an open space on the back cover, where springmakers can stamp their identification to promote themselves with customers. Handbooks with custom-printed covers (name and logo) in quantities of 250 or more are also available. Call SMI at (630) 495-8588 for pricing.

Handbook Table of Contents

D. Helical Extension Springs
Introduction
Initial Tension
Types of Ends
Extension Spring Dimensions
Design Equations
Choice of Operating Stress - Static
Choice of Operating Stress - Cyclic
Clearances
Tolerances
How to Specify
Extension Spring Design Example
Final Design Specifications

E. Torsion Springs
Introduction
Number of Turns
Mean Diameter
Length
Spring Rate
Stress
End Configurations
Choice of Operating Stress - Static
Choice of Operating Stress - Cyclic
Double Torsion Springs
Rectangular Wire
Tolerances
How to Specify
Design Example
Final Design Specifications
Symbols for Spring Terms

F. Tolerancing Guidelines
Introduction
Warning
Compression Spring Load Tolerances
Quality Grades for Load Tolerances
Compression Spring Free Length Tolerances
Extension Spring Load Tolerances
Quality Grades for Extension Spring Load
Tolerances
Extension Spring Free Length Tolerances
Torsion Spring Load Tolerances (Torque)
Quality Grades for Torsion Spring Load
Tolerances
Tolerances for Hot Coiled Springs