Custom Springs

We are ready to take on any challenge!


From large springs to small springs, here we introduce our springs that never fail to live up to expectations.

Torsion Springs

We can manufacture torsion springs up to 40mm in wire diameter!
Therefore, they can handle a high torque.

Features Of Our Springs

Torsion springs are mainly used as coil springs that are subject to torsional moments. The end parts also come in various shapes, and the spring can be used according to their shape depending on how the spring will be used as well as how and where it will be mounted. There is also a so-called double torsion spring, which has a shape in which the coil parts are connected and can produce twice the torque at the same twist angle.

A Huge Variation of Springs Available

With our accumulated know-how, we will make the perfect design proposal to you according to the rotation direction and mounting method used. We can manufacture custom-made torsion springs with a wide variety of materials, from ordinary spring steel to special steel, by selecting materials that suit your specification environment.

Key Points on Our Devotion to Handmade Springs

The shapes of the end parts (arms) are often complex because the torsion spring has a wide variety of uses, but by hand, we can bring to life shapes that cannot be produced with machines.
Our craftsmanship also achieves ultra-high dimensional accuracy and torque characteristics for the aerospace field.

  • We support design and production even for small lots of one or two springs
    In the spring industry, our “complete custom-made production & high-mix, low-volume manufacturing” is an extremely unique production system which has not changed since our founding.
    We guarantee to deliver the quantity you need, when you need it, at high quality.
  • We support all kinds of environments with the likes of heat resistance, corrosion resistance, and durability
    Springs are very sensitive to high and low temperatures and corrosive atmospheres such as rust. Tokai Spring conducts daily verification tests to properly maintain the performance of our springs in any environment such as at temperatures of 100°C or higher, -20°C or lower, as well as for applications in which our springs are exposed to seawater or industrial water!

Specifications for Our Torsion Springs

Spec category Item Specification
Performance specifications Load characteristics Max. torque 1 kN・m
Torque allowance Standard ±15%
Torque measurement range Max. 200°
Dimensions D/d 3.0∼20.0
Free length allowance Standard ±3.0%
Coil diameter allowance Standard ±1.5%
Relative arm angle Standard 10°
Durability Standard durability improvement processing Shot peening
Durability Static (1000 or less loading cycles)
Material SUP10(Correspond to 51CrV4,6150) Chrome-Vanadium steel for spring Wire diameter: φ13∼25 Material length: 8 m
Conditions of use Indoor working temperature -50∼180℃ *1
Rustproofing Adhering specification Coated with anti-rust oil
Non-adhering specification Coated with anti-rust oil
Coated with black powder (Polyester resin)
Electrodeposited black coating
Dacrotized finish
Disgo plating
  • *1:Product allowable stress varies according to temperature. For more information, speak with a Tokai Spring industries engineer.
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