The core structural characteristics of extension springs are as follows:
Body Configuration: They are helical springs designed to withstand axial tensile force. Typically wound from material with a circular cross-section, the coils are tightly wound against each other with no gaps in the unloaded state-distinguishing them from compression springs, which require spacing between coils in their free state.
End Structure: Both ends feature hook-like connection structures. Common types include round hooks, side hooks, and adjustable hooks, facilitating installation and securing while suiting various application scenarios.
Inherent Properties: They possess built-in initial tension after forming, which eliminates wobbling caused by assembly clearances; they offer stable elasticity and provide consistent restoring tensile force.
