Fast Product Search - enter part #

or click here for Advanced Search
Certified ISO 9001:2008 
 
 

Torsion Springs

Stock sizes in stainless steel and music wire

SPEC stainless steel torsion springs are widely useful to store and release energy of rotation or to maintain a pressure over a short distance. Our stock selection includes torsion springs with four end positions and music wire springs with three end positions as shown in the drawings. SPEC torsion springs are normally used over a supporting mandrel or arbor. Suggested mandrel sizes allow about 10% clearance at the deflections listed. If greater deflections are used, the arbor size should be reduced. Sufficient room (minimum axial space) must be provided in the assembly for the spring to function properly. SPEC torsion springs should be used in the direction that winds the coils. In the unwinding direction that winds the coils. In the unwinding direction the maximum load is lower because of residual stresses. Torque values listed are suitable for average conditions. These values can be increased about 20% for static conditions with only slight setting.

Material

  • Stainless Steel
    Commercial Type 302 ASTM-A313 or AMS 5688 (chemical and physical only)
  • Music Wire
    ASTM-A228 or AMS 5112
    Certificate of compliance available on request.

Ends

Straight torsion ends are standard.

Special end treatment available. Allow additional time.

Finish

Plain finish is standard. Allow additional time for special finishes.

Tolerances

Torque is for reference only and should not be specified.
O.D. ±5% Stainless Steel
±2% Music Wire

For inspection purposes, the load should be applied at ½ leg length (E). Using other lengths appreciably alters the active length of wire and affects the test results. 

The reference torque values listed can be translated to the approximate direct load by using the formula P = M/En where P is the load applied at the new length. En.

  • Example: for part T012-090-055, what is the load when En = 0.187? P = M/En = 0.047/0.187 = 0.25lb.

Torque values at intermediate deflections can be computed by direct proration. Example: For part T030-180-250, the torque at 90° deflection is 0.312 in-lb (35.3 N-mm).