Piston rods

Jansen produces tubes for piston rods in shock absorbers for automotive engineering. The demands to these tubes are varied. Processing and refining the outer surface requires excellent tube surface qualities. High levels of reforming properties and homogeneous reforming characteristics are required for swaging tube ends and rolling the thread. Tight tolerances guarantee efficient piston rod production as part of production processes. High levels of material purity guarantee the fatigue strength of shock absorbers. The demand for light-weight design can only be met by using high-tensile materials.

Tube Requirements

  • Excellent surface condition
  • Excellent surface-finish condition
  • High levels of fatigue strength
  • Very good geometrical accuracy
  • Good formability (sufficient elongation)

Material properties

  • High strength (YS, TS) and fatigue strength
  • Homogeneous strength properties and ductility
  • Potential to reduce wall thickness

Structure

  • Homogeneous, fine-grain structure in weld seam and basic material
  • Minimised surface decarburisation of inner and outer surfaces (< 100 μm)
  • Excellent weld seam quality

Geometry

  • Minimised fluctuations in wall thickness and inner/outer diameter
  • Minimised deviations in straightness
  • Minimised deviations in concentricity and axial run-out
  • Minimised eccentricity
  • Specific tube end processing: sawn/brushed; chamfered

Surface

  • Excellent surface condition
  • Minimised surface flaws (adhesions, scratches, dents, etc.)
  • Increased surface hardness thanks to surface coatings/hardening
  • Minimised corrosion protection, optionally specific corrosion protection
Piston rods