Torsion Springs
Custom torsion springs,
formed in Thailand.
Torsion springs that store rotational energy — with leg geometry, wind direction and torque matched to the assembly, in wire from 0.08 mm to 8.0 mm.
Torque, angle and leg geometry have to agree
A torsion spring is defined by the torque it delivers at a given deflection angle, not by coil count alone. We wind to the body dimensions on your drawing, form the legs to the required orientation, and test torque on a torsion tester before shipment.
Mandrel diameter, wind direction and leg form all affect how the spring sits and works in the assembly. If the drawing leaves one of these open, we ask before production.
- Left-hand and right-hand winds
- Straight, bent, hooked and custom leg forms
- Torque testing at the specified deflection angle
- Carbon spring steel and stainless steel
Where torsion springs turn a mechanism
Torsion springs apply a turning force over a defined angle. The leg position and mandrel diameter are usually the features that decide whether the part fits and works.
Torsion spring specifications
Current production is shown below. Torque, leg geometry and mandrel size are reviewed together at RFQ.
| Parameter | Capability |
|---|---|
| Wire diameter | 0.08–8.0 mm in current production. Planned expansion to 12.0 mm as new equipment is installed. |
| Materials | 65Mn, 72A, 82B, 60Si2Mn; stainless steel 301, 302, 304 and 316. |
| Leg forms | Straight, bent, hooked and custom leg geometries to drawing. |
| Wind direction | Left-hand or right-hand. |
| Heat treatment | In-house stress relief and tempering. |
| Surface finish | Anti-rust oil, electrophoresis (E-coat), zinc plating, nickel plating, spray coating. |
| Wire tolerance | JIS wire tolerance by grade (JIS G 3521, JIS G 3522 or JIS G 4309). ASTM wire specification and SMI commercial tolerances available for US programs. |
| Torque testing | Torque at the deflection angle specified on the drawing. |
| Dimensional inspection | 2.5D vision measurement of body diameter, leg position and wire dimensions. |
| Quality system | ISO 9001:2015 and ISO 14001:2015. |
| Samples | Prototype and pre-production samples against drawing. |
Wire diameter is inspected to the JIS tolerance of the ordered wire grade. For US programs, we can quote and inspect to the relevant ASTM wire specification and SMI commercial tolerances.
Materials and finishes
The wire grade and finish should follow the load, fatigue and corrosion exposure of the application — not a default.
65Mn · 72A · 82B · 60Si2Mn
Selected for the torque, deflection and cycle life of the application, with heat treatment matched to the wire grade.
301 · 302 · 304 · 316
Used where moisture, cleaning or a corrosive environment makes a coated carbon spring unsuitable.
Oil · E-coat · zinc · nickel · spray
Anti-rust oil, electrophoresis, zinc plating, nickel plating and spray coating are available for the body and formed legs.
Torque measured at the angle on your drawing
A torsion spring that looks right can still deliver the wrong torque. We measure it on a torsion tester and check the leg geometry against the drawing.
- Raw material tensile strength and metallographic structure
- Torque at the specified deflection angle
- 2.5D vision measurement of body and leg dimensions
- Salt spray testing for plated and coated parts
- Fatigue testing for cycle-life validation
- Inspection records agreed at RFQ
What to send with your drawing
A complete drawing shortens the quote and removes assumptions.
- Wire diameter and material grade
- Body diameter and coil count
- Leg angle, leg length and orientation
- Torque at a specified deflection angle
- Wind direction and mandrel diameter
- Surface finish and annual quantity
PDF, DXF, STEP or a clear photo
Email your drawing to info@aofengspringthailand.com. We confirm the leg form, wind direction, wire range and test plan before quoting.
Torsion spring questions
Can you hold a specified torque at a given angle?
Yes. We test torque at the deflection angle on your drawing on a torsion tester and report the result.
Which leg forms can you produce?
Straight, bent, hooked and custom leg geometries to drawing, with the leg orientation set against your assembly.
Do you make both wind directions?
Yes, left-hand and right-hand winds are both available.
What wire range and materials are available?
0.08–8.0 mm in current production, with a planned expansion to 12.0 mm. Materials include 65Mn, 72A, 82B, 60Si2Mn and stainless steel 301, 302, 304 and 316.
Send a drawing, get a quote
Tell us the torque, angle and leg geometry. We will confirm the wind direction, wire range and test plan before quoting.
AOFENG SPRING (THAILAND) · Rayong, Thailand