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Explore the information below to find technical advice on extension springs specifications, such as how to specify spring dimensions. Plus, learn about wire diameter sizes that we can coil into extension springs, as well as the most common types of ends, loops and hooks.Contact Us
Explore industry-standard abbreviations for extension spring dimensions as well as calculations for free length and mean coil diameter. These notes and the diagram in Figure 1 are sourced from the Handbook of Spring Design by the Spring Manufacturers Institute (SMI).
Extension spring formulas can help you find several other values as well. Learn how to measure extension springs and their initial tension in this easy-to-read extension spring resources guide.
Ready to request a quote? Download the checklist to help you specify the critical dimensions we’ll need to quote your extension springs. For help with your extension spring design, please call us at 708-453-2570.Download the Checklist
Extension Spring Wire Diameter
Extension Spring Materials
Common Extension Spring Ends
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