Extension Springs

Australian made extension springs

Marsh Alliance, as industry-leading experts specializing in the bespoke design and fabrication of industrial extension springs, is fully equipped to meet the precise requirements of your project. We offer an extensive range of spring wire diameters, ranging from 0.25mm to 16mm, and have the capability to customize wire diameter, outside spring diameter, overall length, rate, maximum load, solid height, and coil count to suit your exact specifications.

Our material selection encompasses hard-drawn, galvanized steel, 304 and 316 grade stainless steel, and oil-tempered materials, all tailored to align perfectly with your specific application needs. Be it single prototypes, once-off production runs, or large-scale batch manufacturing in the millions, our facilities are adaptable to accommodate diverse production demands.

With a sprawling 7,000 sqm production facility and a comprehensive array of over 300 specialized machines, we uphold a commitment to delivering consistent and reliable results. Our production method involves cold coiling, complemented by in-house stress relieving and strengthening processes.

Clients from a broad range of industries and markets rely on Marsh Alliance for their custom made extension springs. Over the years, we have fabricated millions of extension springs for use in trampolines, screen doors, exercise equipment, tape measures and everything in between.

Get a quote for custom designed extension springs

Follow this measurement guide to populate our online form:

1 Measure your spring

2 Choose a hook type

4 Material and load

Specify the material type.
Load on an extension if known (kg/N)
Extension travel if know (mm)

3 Hook orientation

4 Material and load

Specify the material type.
Load on an extension if known (kg/N)
Extension travel if know (mm)

A little bit about extension springs

Extension springs have end loops or other contrivances to connect the spring body to the component in which they operate. Force needs to be applied to separate the coils, the so-called initial tension. The body of extension springs is stressed in torsion, but the end loops are stressed in bending, and the direction of bending is the opposite to that in which the spring is coiled. For this reason the position of maximum stress in extension springs is always the end loop when the spring is made from one piece of wire, and the loop is the same diameter as the body of the spring. The end loops are usually placed over the central axis of the body of the spring, which means that the body will stay straight when loaded.

In comparison to compression or torsion springs, extension springs are better-suited for applications which require straight-line motion or linear force. Torsion springs produce rotational force, while compression springs exert force in the opposite direction of their compression. Additionally, extension springs allow for easy adjustment of tension by altering the amount of extension or the position of the attached ends, making them ideal for applications where tension requirements may change.

Not sure if a custom designed extension spring is right for your project? Talk to Marsh Alliance today for advice.

Why choose Marsh Alliance?

Marsh Alliance has been Australia’s largest spring manufacturer for a number of years and has expanded to offer a wide range of other products. Many of our 100+ employees are long serving team members, some with up to 40 years of service making springs with us! That deep manufacturing knowledge is backed up by the latest state-of-the-art CNC equipment complementing hand coiled methods.

We are relied upon by some of Australia’s biggest names in manufacturing as an integral part of their supply chain. By choosing us, you’ll benefit from short lead times, enabling you to meet your project deadlines or operational needs with ease. As a local company, we understand the unique requirements of the Australian market and comply with rigorous industry standards. Additionally, our dedicated customer support team is always available to address your queries, offer technical guidance, and provide personalised assistance at every stage of the process.

In addition to shipping around Australia, we can also deliver to New Zealand, the Americas, Asia and Europe.

If you have any questions, please feel free to give us a call on 07 3271 3500.