Tension springs work in the opposite way as gas springs, i.e. the piston rod is pulled towards the inside by means of the gas pressure in the cylinder. The spring force F1 results from the internal pressure (160 bars without load at the most) in the cylinder, which is generated by the filling medium nitrogen. In the tension spring, the piston ring area between the piston rod and the inside cylinder diameter is decisive. When no load is applied, the piston rod always is compressed. The tension springs of series ‘Z’ have no damping. The series ZD is available with damping and series ZX is available as locking tension spring.

HAHN tension springs are available in steel, in AISI 303/304 and AISI 316L / 316Ti.