Tension Springs & Extension Springs

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All dimensions entered as:
Standard (mm / in)
Metric (mm / in )
1. Outside Diameter
mm/ in. +/- mm/in.
2. Inside Diameter
mm/ in. +/- mm/ in.
3. Torque
mm/ in.• lb. +/-
mm/in.• lb.  @
4. Length of space available
mm/ in.
5.Maximum wound position
turns or degrees from free position.
6. Degree of Movement
mm/ in.
7. Direction of helix
8. Type of ends
9. Type of Material
10. Finish
11. Frequency of movement (cycles/sec)
12. Operating temp
degrees F
13. Wire diameter   mm/ in.
14. Coil diameter     mm/ in.
16. Rate                     mm/ in.
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Tension & Extension Springs

Tension Springs & Extension Springs

Extension springs are springs which absorb and store energy by offering resistance to a pulling force. Various types of ends are
used to attach the extension spring to the source of the force. Extension springs are usually straight, tapered, and conical.

Consider extension spring when you need:

  • Round and Square Shapes
  • Machine Loops, Side Loops, Crossover Center Loops, Extended Loops, and Loops Custom to your Design

Tension Springs Extension Springs Tension & Extension Springs
D (wire diameter):  This parameter describes the diameter of wire used as material for spring.
De (External Diameter):  External diameter at large end of the spring. Tolerance for this parameter is (+-)2%(indicative). 
Ds (Internal Diameter):  Internal diameter at small end of the spring. Tolerance for this parameter is (+-)2%(indicative) 
B.L (Body length):  Body length of Extension springs is measured in its uncompressed state Tolerance for this  parameter is (+-)2%(indicative).
F.L (Free length) :  Free length means distance between two hooks .(Inside Hooks)
R (spring rate): This parameter determines spring's resistance, while it is working. It is measured in 1
DaN/mm = 10 N/mm. Tolerance for this parameter is (+-)15%(indicative).


Extension Springs Tension Springs Extension Springs