In the thread rolling method, the thread profile is produced by cold rolling. This process strengthens and smoothes the surface. The natural grain-flow of the material is not interrupted.
   In a further working stage, the surface of the rolled-thread bars is inductively hardened. The hardening depth, depending on the dimensions, is approximately 1.5 mm. The hardening process leaves the surface with rubberised polishing discs. Before the screw is then stored in the high-level shelving system, the required straightness is ensured in the straightening press.
   Each manufacturing stage requires great care and experience by the machine operators. At NEFF this expertise is readily available due to our company's long tradition of screw drive production.
      Gewinde mit gotischem Profil (Spitzbogenprofil)
      Diameter 12 to 63 mm (MICRONLine: 12 to 40 mm)
      Lead 5 to 50 mm (MICRONLine: 5 to 40 mm)
      No. of starts 1 - 5
      Thread direction right hand thread (KGS 2005 also left hand thread)
      Length 5600 mm (1300 mm for KGS 1205)
      Material 1.1213 (Cf 53), Ball track inductively hardened and polished. Soft-annealed screw end and core
      Pitch accuracy 50 μm / 300 mm (MICRONLine: 23 μm / 300 mm)
      Straightness at length
      L < 500 mm : 0,05 mm/m,
      L = 500 to 1000 mm : 0,08 mm/m,
      L > 1000 mm : 0,1 mm/m
      End treatment to customer requirement