A double bodied torsion spring, with two coil bodies joined by a centre leg, zinc plated for chair and seating mechanisms. The twin body doubles the available torque without doubling the length of a single coil stack, which is why seating mechanisms use this form so often.
Two bodies working together give the torque of a much longer single spring while fitting a short shaft.
With a body on each side of the centre leg, the load on the shaft is symmetrical rather than offset.
Underseat mechanisms are largely hidden, so zinc gives the protection needed without paying for a decorative finish.
Check that the centre leg is fully engaged before the mechanism is loaded. A centre leg that slips out transfers all the torque to one body and overloads it immediately.
Single body springs too long to fit the available shaft in a seat mechanism
Offset spring loads that wear one side of a pivot faster than the other
Dimensional and load figures are set per order against your drawing or sample, so they are marked TBC rather than filled with catalogue numbers.
| Product Type | Torsion Springs |
|---|---|
| Raw Material Options | Stainless steel, Spring steel, Carbon steel, 65Mn, Music wire |
| Wire Diameter Range | 0.1-8 mm |
| Surface Treatment Options | Zinc plating, Nickel plating, Silver plating, Gold plating, Tin plating, Galvanizing in various colours, Dacromet, Black oxide, Phosphating |
| Standard | ISO, non-standard and OEM drawings |
| Processing Route | Material sourcing → Coiling and forming → Heat treatment → Surface treatment → Quality inspection → Packing → Shipping |
| Inspection Equipment | Grinding and shot peening machinery; Precision tensile strength testers; Magnetic powder flaw detectors |
| Packing | Plastic bags, cartons or pallets, or packing to your own specification |
| Payment Terms | L/C, T/T, D/A, D/P, Western Union, 30% deposit before production, 70% balance before shipment |
| Lead Time | 7-15 days after the order is confirmed |
| Minimum Order Quantity | Quoted per part — tell us your requirement (TBC) |
| Dimensions and Load Rating | Made to your drawing or sample (TBC per part) |
Every batch follows the same seven step route, with tensile testing and magnetic powder flaw detection carried out before packing.
Available in Stainless steel, Spring steel, Carbon steel, 65Mn, Music wire, in wire from 0.1-8 mm, with any of our nine surface finishing routes. Geometry, end treatment and finish are all specified per order.
ISO 9001, SGS certificate and RoHS report (stated on the legacy site, certificates pending re-confirmation). Certificate copies are sent on request once re-confirmed.
Against two separate single torsion springs, the double bodied part guarantees both halves are matched and halves the number of components to handle on the line.
No, and normally they are opposite hands so that both wind up when the centre leg is loaded. That is what makes the design work.
Yes. The centre leg is formed to engage whatever part of your mechanism drives it.
For the same shaft length, usually yes, because the torque comes from two bodies rather than one.
Send your drawing, dimensions or a sample. We will confirm the specification and come back with a price and a lead time.