Torsion systems are the primary systems used to operate garage doors, consisting of a torsion spring mounted on an axle, also referred to as a torsion tube. This is responsible for generating the torque necessary for lifting and carrying the weight of the door. While one torsion spring can be used, it does come with two main disadvantages.
Safety Risks If Breakage Occurs
When a torsion spring is deflected it conserves the mechanical energy or torque required to lift the weight. However, due to their constant operation under high levels of stress, fatigue eventually becomes an issue leading to three possible phases: initiation crack, propagation crack and breakage/failure. Factors that can influence its lifespan include friction, operating load, number of active coils, environment and material strength. With one torsion spring if failure occurs there is no torque left to carry the full mass of the garage door; however if two or more springs are installed then this issue can be avoided.
Opposite Direction Pressure
When raising the garage door, the spring is unwound twisting back to its equilibrium condition which causes unextending of its coil. With just one torsion spring there is no counterforce from another side causing continuous pressure on components such as bearings, cables, pulleys, hinges and rollers resulting in misalignment and grinding of shafts along with premature wear and tear on other parts. Having two springs installed helps alleviate these issues by providing balance for this pressure while also providing safety should one fail.
In conclusion it is highly recommended that two torsion springs be installed in order to ensure safety when lifting your garage door along with reducing any potential damage caused by its components being subjected to excess force in only one direction.