- axial deflection
- axial offset. helical
- torsional stress
Helicity, also commonly referred to as torsion or twisting, is understood to be a curvature course adopted by wire radially rather than axially upon leaving the curvature plane. Such a curvature course can be intentional, as in the production of rope and cable where it is called the lay length, and in the production of springs where it is called the pitch.
Helicity is an undesirable condition for all follow-up processes if it is not specifically created for the product but arises unintentionally due to certain production factors. Frequent causes of helicity include overhead pulling off, static unwinding and unspooling, incorrect deflecting, frequent changes of direction, and any faulty process transitions with a negative effect on round material which rotates during processing.
Inconstant or indeed alternating helicities not only impede the process flow but also rule out final products of any required constancy.
Aids such as helix straighteners, killing-straighteners and additional straightening systems can go a long way in solving the problem. Above all, however, it is important to avoid the avoidable and to create a constant process.