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.
- Tokai Spring HOME
- Custom Springs
- Extension Springs
Extension Springs
We can manufacture extension springs up to 30mm in wire diameter!
Therefore, they can handle high loads
Features Of Our Springs
Extension coil springs are generally used for applications in which a load is applied in the tensile direction, and therefore both ends are often hook-shaped, but the ends can come in various different shapes. Features of the extension coil spring are that it is a spring with a small diameter that does not undergo heat treatment after winding. It is possible to apply initial tension to the extension coil spring, and it can generate an appropriate load without gaps between the wires when tension is applied.
Our Extension Coil Springs Are Also Compatible with Metal Fittings
Our Extension Coil Springs Are Also Compatible with Metal Fittings
EXtension coil springs can also be used for both compression and tension by inserting screw fittings at both ends and using rod ends instead of hooks. When using a extension coil spring for pushing or pulling, consider using one with a metal fittings.
Key Points on Our Devotion to Handmade Springs
As our springs are not automatically formed by a machine, we can make hook shapes that cannot be machined and control the initial tension, and machine the spring to fit your application.
-
- 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 Extension Springs
Extension Spring With Hooks
| Spec category | Item | Specification | |
|---|---|---|---|
| Standard specifications | Load characteristics | Load | Max. 1.5ton |
| Load allowance | Standard ±10% | ||
| Spring constant allowance | Standard ±10% | ||
| Max. measured length: | 1100mm | ||
| Dimensions | D/d | 5.0∼15.0 | |
| Free length allowance | Standard ±2.0% | ||
| Coil diameter allowance | Standard ±1.5% | ||
| Durability | Standard durability improvement processing | Shot peening(Non-adhering specification) | |
| Durability | Static(1000 or less loading cycles) | ||
| Material | SUP10(Correspond to 51CrV4,6150) Chrome-Vanadium steel for spring | Wire diameter: φ13∼25 Material length: 8m | |
| 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.
Fitting-type, Extension Spring
| Spec category | Item | Specification | |
|---|---|---|---|
| Standard specifications | Load characteristics | Load | Max. 10ton |
| Load allowance | Standard ±10% as installed and at max. | ||
| Spring constant allowance | Standard ±10% | ||
| Max. measured length: | 1100mm | ||
| Dimensions | D/d | 5.0∼20.0 | |
| Free length allowance | Standard ±2.0% | ||
| Coil diameter allowance | Standard ±1.5% | ||
| Durability | Standard durability improvement processing | Shot peening (Non-adhering specification) | |
| Durability | Static(1000 or less loading cycles) | ||
| Material | SUP10(Correspond to 51CrV4,6150) Chrome-Vanadium steel for spring | Wire diameter: φ13∼25 Material length: 8m | |
| Wire diameter: φ26∼90 Material length: 12m | |||
| 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 | |||
| Customspecifications | Material | Specifications by material | SUP10(Correspond to 51CrV4,6150) Wire diameter: φ26∼90：Material length: 14.7m |
| Durability | Material surface improvement | Hot-rolled skin removal | |
- *1：Product allowable stress varies according to temperature. For more information, speak with a Tokai Spring industries engineer.
Push-pull springs for tuned mass damper
| Spec category | Item | Specification | |
|---|---|---|---|
| Standardspecifications | Load characteristics | Load | Max. 15 ton |
| Load allowance | Standard ±10% as installed and at max. | ||
| Stroke | Max. ±200 mm | ||
| Spring constant allowance | Standard ±10% | ||
| Max. measured length: | 1100 mm | ||
| Dimensions | D/d | 5.0∼15.0 | |
| H/D | Max. 2.5 | ||
| Free length allowance | Standard ±2.0% | ||
| Coil diameter allowance | Standard ±1.5% | ||
| Durability | Standard durability improvement processing | Shot peening | |
| Durability | Dynamic Max. 2 million loading cycles | ||
| Material | SUP10(Correspond to 51CrV4,6150) Chrome-Vanadium steel for spring | Wire diameter: φ13∼25 Material length: 8 m | |
| Wire diameter: φ26∼90 Material length: 12m | |||
| Conditions of use | Indoor working temperature | -50∼180℃ *1 | |
| Rustproofing | Standard | Coated with anti-rust oil | |
| Coated with black powder (Polyester resin) | |||
| Electrodeposited black coating | |||
| Dacrotized finish | |||
| Disgo plating | |||
| Other | |||
| Customspecifications | Material | Specifications by material | SUP10, Wire diameter: φ26∼90, Material length: 14.7 m |
| Durability | Material surface improvement | Hot-rolled skin removal | |
- *1：Product allowable stress varies according to temperature. For more information, speak with a Tokai Spring industries engineer.
Spring Design
Search By Industries
