Extension spring
Extension spring
Extension springs are close-wound helical springs with end hooks. They store elastic energy under tension and rebound to original length once the pulling force is released. Made of high-carbon steel or stainless steel, they deliver stable tension and long fatigue life. Custom sizes, spring rates and hook styles are available. Widely used in machinery, hardware and Pilates equipment for controlled return force. Inspect regularly to avoid over-stretching and ensure safe operation.
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Products
| Product name | extension spring |
| Material | Spring steel（SWC），Music wire（SWP），Stainless steel（SUS）,Mild-carbon steel,，Phosphor copper，60Si2Mn，55CrSi，T9A，A3，Titanium alloy, Nickel-plated wire, Galvanized wire, Tin-plated wire, Enameled wire |
| Surface treatment | Zinc plating, Nickel plating, Anodic oxidation,Black oxided,Electrophoresis, Power coating, Gold plating, Silver plating, Tin plating, Paint,Chorme, Phosphate, Dacromet,Oil coating, Copper plating, Sand blasting, Passivation, Polishing,Etc |
| Packing | PE bags, Cartons, Pallets,Customized according to customer needs |
| Application | Automobile hardware parts, Electrical equipment, Electronic products, Medical equipment, Gym equipment parts, Industrial equipment, Mechanical parts, Office equipment, Children’s toys, Etc. |
Corrosion Resistance: Made from SUS 304 and 316 stainless steel providing 800 to 1,200 MPa tensile strength, withstanding 200+ hours of salt spray without degradation, ensuring long-term durability in industrial, outdoor, and marine environments where reliability under humidity and chemical exposure is critical.
Precision Engineering: Customizable wire diameters from 0.2 to 8.0mm and free lengths from 3 to 200mm, rapid 5-day prototyping, with ±0.05mm dimensional tolerance, enabling precise OEM specifications, consistent force output, and seamless integration into machinery, household devices, and commercial display systems.
Durability: Double-hook design supports static loads up to 10 kg with 360° rotation, tested through 50,000 operational cycles, providing dependable suspension, secure hanging, and reliable performance for retail displays, mechanical assemblies, and repeated daily-use applications.
Safety Compliance: RoHS-compliant materials with lead content below 0.1%, verified by third-party testing, ensuring suitability for food processing equipment, children’s products, and other applications requiring non-toxic, environmentally safe spring components.
Customizable Performance: Springs offer ±3% force deviation under repeated loading, maintain structural integrity over 50,000 cycles, and can be adjusted in stiffness and length for tailored applications, supporting bulk orders, repeat procurement, and high-volume industrial or commercial projects with minimal maintenance.
