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Production Engineering

, Volume 7, Issue 2–3, pp 177–184 | Cite as

Presentation of a novel cutting technology for precision machining of hardened, rotationally symmetric parts

  • Fritz Klocke
  • Thomas Bergs
  • Florian Degen
  • Philipp Ganser
Production Process

Abstract

In this paper a new cutting technology similar to hard turning is presented to cut rotationally symmetric parts made of hardened materials. This novel technology, which is named rotational turning, is based on a combination of hard turning and circular milling. An analytical model is developed to describe the engagement parameters between tool and workpiece. It is shown by the model, that the virtual tool corner radius in rotational turning, which takes effect during the cutting process, is more than 50 times larger than in state of the art hard turning. Due to this, feed marks, which are common in turning, can be reduced to a level, where they are not measurable anymore. It can be shown in experiments, that the minimum achievable surface roughness is therefore not limited by the feed rate anymore, like in turning processes usual, but by other effects like the waviness of the cutting edge.

Keywords

Rotational turning Hard turning Kinematic surface roughness model 

List of symbols

agr

Depth of grooves

ap

Depth of cut

f

Feed

fax

Feed caused by axial tool movement

frot

Feed caused by tool rotation

fvirt

Virtual feed

h

Pitch hight

hc

Undeformed chip thickness

hcu

Minimum undeformed chip thickness

l1

Workpiece length

l2

Tool length

lc

Axial contact length

lrest

Difference between tool and workpiece length

n1

Workpiece revolution

n2

Tool revolution

r1

Workpiece radius

r2

Tool radius

rgr

Radius of the cutting grooves

rt

Radius of the helix top

rvirt

Virtual tool corner radius

rε

Tool corner radius

Ra

Average roughness

Rt

Theoretical kinematic surface roughness

Rz

Average roughness depth

t

Time

tax

Time for axial tool movement

trot

Time for tool rotation

vax

Axial tool velocity

vc

Cutting velocity

vrot

Axial velocity caused by tool rotation

VB

Width of flank wear

α1

Workpiece contact angel

α2

Tool contact angel

λ

Helix angle

λc

Cut-off length

References

  1. 1.
    Guo YB, Warren AW (2008) The impact of surface integrity by hard turning versus grinding on fatigue damage mechanisms in rolling contact. Surf Coat Technol 203:291–299. doi: 10.1016/j.surfcoat.2008.09.005 CrossRefGoogle Scholar
  2. 2.
    Stier H (1988) The rewards and demands of hart-part turning. Modern machine Shop, April issueGoogle Scholar
  3. 3.
    Denkena B, Boehnke D, Meyer R (2008) Reduction of wear induced surface zone effects during hard turning by means of new tool geometries. Prod Eng Res Dev 2:123–132. doi: 10.1007/s11740-008-0089-1 CrossRefGoogle Scholar
  4. 4.
    Kummer N (2004) Verfahren und Vorrichtung zum spanenden Bearbeiten rotationssymmetrischer Flächen eines Werkstücks. Patent DE102004026675C5Google Scholar
  5. 5.
    Denkena B, Tönshoff KH (2011) Spanen—Grundlagen. Springer, BerlinGoogle Scholar
  6. 6.
    Klocke F (2011) Manufacturing processes 1—Cutting. Springer, BerlinCrossRefGoogle Scholar
  7. 7.
    Deutsches Institut für Normung e.V. (1998) Geometrical product specifications (GPS)—Surface texture: profile method—Rules and procedures for the assessment of surface texture. DIN EN ISO 4288:1998–2004Google Scholar
  8. 8.
    Brammertz PH (1961) Die Entstehung der Oberflächenrauheit beim Feindrehen. Industrieanzeiger Nr 2:25–32Google Scholar

Copyright information

© German Academic Society for Production Engineering (WGP) 2012

Authors and Affiliations

  • Fritz Klocke
    • 1
  • Thomas Bergs
    • 1
  • Florian Degen
    • 1
  • Philipp Ganser
    • 1
  1. 1.Fraunhofer Institute for Production Technology IPTAachenGermany

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