Custom Extension Springs for Reliable Tension and Return Force
Custom Extension Spring Manufacturer
JL Springs manufactures custom extension springs for applications requiring stable tension, controlled extension, and reliable return performance. We support production based on drawings, samples, or technical specifications for OEM, industrial, and export projects.
Specifications
Custom Extension Spring Specifications
View a selection of custom extension springs manufactured for OEM, industrial, fitness equipment, luggage hardware, mobility, and mechanical applications.
Wire Diameter：
0.2 mm to 6 mm
Material Options：
Stainless steel, music wire, carbon steel, alloy spring steel, copper wire, iron wire, and other materials based on application requirements
：
Outer Diameter Coil Diameter
Outer diameter and coil diameter can be customized according to installation space, load requirements, and drawing specifications
Hook / Loop Configuration
：
Machine hooks, extended hooks, side hooks, double loops, and custom end forms are available
Initial Tension ：
Initial tension can be adjusted according to load requirements, extension length, and application performance
Surface Finish ：
Plain, zinc plated, nickel plated, powder coated, and other finishes upon request
Understanding an Extension Spring Drawing
This guide helps buyers and engineers identify the key dimensions and configuration details commonly required for custom torsion spring quotation and production. It shows the standard torsion spring parameters and provides six common leg-end references for easier communication and specification.
Quotation Information
-
Material
-
Wire Diameter
-
Outside Diameter
-
Free Length
-
Hook Type
-
Initial Tension / Spring Rate
-
Surface Finish
-
Quantity / Application
Full Loop at Side
Long Rounded End Hook Over Center
Long Extended Hook
V Hook Over Center
Long Square End Hook Over Center
Side Hook
Small-Batch Customization
Low-volume support
Dedicated Project Support
Sales + technical team
Fatigue Life & Durability
Built for repeated use
Fast Sampling & Revisions
3–5 working days
Surface Finish Options
Corrosion resistance
Stable Mass Production
Batch consistency
What Are Extension Springs?
Extension springs are designed to store and release energy when they are stretched. When an external force pulls the spring apart, the spring generates tension to pull components back to their original position.
They are commonly used in latches, doors, fitness equipment, tools, luggage hardware, mobility products, and mechanical assemblies that require controlled extension force, return action, or tension support. Hook styles, loop ends, spring length, and initial tension can be customized according to the application.
Material Selection for Extension Springs
Material selection depends on load requirements, initial tension, fatigue life, corrosion resistance, working environment, and cost considerations. Common materials include stainless steel, music wire, carbon steel, and copper wire, iron wire, aluminum wire, alloy spring steel.
For outdoor, humid, or corrosion-sensitive applications, stainless steel or suitable surface treatment may be recommended. For applications requiring repeated stretching, stable tension, or higher durability, material performance and fatigue resistance should be considered during the design stage.
Quality Inspection & Packing
Finished extension springs are inspected for key dimensions, hook shape, free length, outer diameter, surface condition, initial tension, extension force, and batch consistency. For functional projects, sample approval can be arranged before mass production to confirm fit, load, stretch distance, and assembly performance.
After inspection, products are packed according to export and delivery requirements. Proper packing helps protect hook shape, spring body, surface finish, and product quality during storage and transportation.
Machine Setup & Production
After the drawing, sample, or technical specification is confirmed, our technicians set up the forming equipment according to wire diameter, outer diameter, free length, coil count, hook style, initial tension, and extension requirements.
During production, machine settings are adjusted to maintain consistent spring body dimensions, hook geometry, and tension performance. For custom extension springs, experienced setup is important because small changes in hook shape, spring length, or initial tension can affect assembly fit and return force.
START YOUR PROJECT
Ready to Optimize Your Production?
Whether you need a prototype or a high-volume run, our engineering team is ready to assist. Get a response within 24 hours during business hours.
Email Sales Team
Call Us (24/7)
Factory Location
No. 88 Industrial Road, Dongguan City, Guangdong Province, China
Why quote with us
Response within 12/24 hours
Drawing-based customization
Prototype & mass production
RoHS / REACH / ISO support
View Our Other Products
Our compression springs are designed to resist axially applied compressive forces. We utilize advanced CNC coiling technology ....
JL Springs manufactures custom stamped metal parts, brackets, clips, plates, terminals, washers, and precision hardware components for electronics, luggage hardware....
From simple clips to complex 3D wire forms and stamped parts. We utilize 12-axis CNC forming machines to produce intricate parts....
Our helical torsion springs are used to apply a torque or store rotational energy in an assembly. We specialize in producing both single....