Extension Spring Calculator

  • Extension Spring Calculations with an Integrated Initial Tension Slider

The Springulator® offers a robust extension spring calculator tool. With only a few required fields of input, the Springulator lets you check the stress of your extension spring. Our calculator features a unique Initial Tension adjustment slider, which allows you to check the spring's performance and design data at different amounts of initial tension. This can assist you in determining which specifications are best for your spring, and help to provide optimal performance.

Use our web-based version below or download our Springulator® app. Visit the App Store for your iPhone or iPad device, or the Google Play store for your Android device.

extension spring design

Extension Spring Calculations & Stress Check

The Springulator is able to generate a variety of data to assist with the design of your extension spring. Enter the load (P1), load height (L1), free length inside the hooks and wire diameter to calculate data including your extension spring's:

By selecting your material type, the Springulator extension spring calculator is also able to check your design to see if it falls within allowable stress limitations. Click the button and a stress chart will be generated that shows the acceptable stress for your part, and pinpoints the stress at the initial height and load height.

The Springulator extension spring calculator is designed for engineers and designers. It has been built with a number of checks that will not allow you to calculate a spring if the data you have entered will not result in a feasible design. If you aren't sure the Springulator is operating correctly, please enter the following data and check the results on the sample values and results page.

Extension Spring Ends

The Springulator has been designed to calculate extension springs with "standard hook ends". Newcomb Spring manufactures a wide variety of extension spring hook end types, which can be customized to meet your application and design requirements. Each hook end type can affect your extension spring performance. We recommend you consult with your Newcomb Spring engineer to determine how your extension spring end will affect the design.

extension spring quote

Extension Spring Standard Machine End

Initial Tension

The design of an extension spring is affected by the spring's initial tension. The Springulator offers a unique function that allows you to adjust your extension spring initial tension to see how this affects the rate, active coils, part weight, body length and allowable stress. By evaluating all of these factors, and how this data if affected by material selection and manufacturing costs, you can help to determine the percentage of initial tension that best meets your needs. We recommend you speak with a Newcomb Spring engineer before manufacturing your extension spring to check if your design will meet the requirements of your application.

Other Extension Spring Design Considerations

Our online extension spring manufacturing and extension spring design resources includes a variety of information that may assist in your spring design.

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Extension Spring Calculations & Quotes

The Springulator is a useful tool for users who wish to check the stress of a design, calculate extension spring functions and test spring capabilities. Please note all results are for design purposes only and are not guaranteed accurate. Click here to begin to use the Springulator extension spring calculator, or visit our extension spring quote page if you would like to send us a CAD drawing or input your extension spring specifications.

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