Spiral Spring

Spiral torsion springs are made from flat steel and are distinguished by the symmetric spacing between the coils. A spiral spring can exert a rotational torque, though usually only a 360° rotation or less. If the rotation is greater the coils tend to "close out" or come into contact with each other causing the torque to rise rapidly. The torque curve of the flat spiral spring is linear to the degree of rotation. Flat spiral torsion springs are usually used in the industrial, automotive and medical device industries

What is the difference between tension springs and torsion springs?

Torsion springs do not fully extend the way that extension springs fully expand and contract when operating an overhead door, while spiral flat springs turn. A flat coil torsion spring lasts longer due to its sturdiness and can typically last between 15,000 to 20,000 cycles whereas a spiral tension spring can only last around 10,000 cycles. Spiral torsion springs also allow for controlled motion. While extension springs can result in a jerking motion, torsion springs maintain a controlled and steady motion. This controlled motion will keep the door in proper balance, while the rough movement of the tension spring can cause the door to need frequent adjustments. When a door is out of alignment, it can have a tendency to cause damage to other parts of the garage door. Tension springs also need more parts in order to fully function. These extra parts are called sheaves and require a longer cable. Torsion springs, on the other hand, are easy to lubricate and maintain. Finally, when a tension spring breaks, it can be much more dangerous than when a torsion spring breaks. Tension springs have been known to fly through garage windows, car windshields and can cause major damage if they collide with a person. When a torsion spring breaks it may cause a loud sound but it does not fly off, rather the spring stays on the shaft.