Green Cutting using Supersonic Air Jets as Coolant and Lubricant during Turning Authors Andrea...

Green Cutting using Supersonic Air Jets as Coolant and

Lubricant during Turning

Authors Andrea Bareggi (presenter) Andrew TorranceGarret O’Donnell

ICM

R 2

006

Department of Mechanical and Manufacturing Engineering

The University of Dublin

Trinity College

Trinity College Dublin

Introduction

Difficult-to-cut materials• Heat resistant alloys• Hard materials• Super stainless alloys (or

super-alloys)


ICM

R 2

006

Introduction

Difficult-to-cut materials• Heat resistant alloys• Hard materials• Super stainless alloys (or

super-alloys)


ICM

R 2

006

• Nickel base alloys• Cobalt base alloys• Titanium alloys• Iron base (high chromium

stainless steel) after Seco Technical Guide, Turning Difficult-To-Machine Alloy, S. Miller, Advanced materials means advanced engines, Interdisciplinary Science Review, vol.21 (2) (1996) pp.117-129

CoolantsTrinity College Dublin

ICM

R 2

006

• Thermal damage

After P. Dahlman, M. Escursell / International Journal of Machine Tools & Manufacture vol.44 (2004) pp.109–115


ICM

R 2

006

• Thermal damage• Wearing by friction



ICM

R 2

006

• Thermal damage• Wearing by friction• Built up edges



ICM

R 2

006

• Thermal damage• Wearing by friction• Built up edges

• Sweeping and cleaning the chip-tool interface

Improving cooling techniquesTrinity College Dublin

ICM

R 2

006

• Reducing cutting forces

• Reducing tool wearing

• Reducing workpiece temperature

• Reducing costs

• Reducing environmental impact

Using air jets: why?Trinity College Dublin

ICM

R 2

006

• Good for environment

• Not toxic for the operator

• Cheap

• Good for chip sweeping

• More likely to penetrate into the chip-tool interface

• Capable of accelerating fluid particles to give better heat transfer

Experimental apparatusTrinity College Dublin

ICM

R 2

006

• Ursus 225 Centre Lathe

• Kistler piezoelectric tool-force dynamometer

• WC inserts with different nose radius

• Supersonic nozzle Silvent 1011

• Hommel roughness tester

• Infrared camera

Test setupTrinity College Dublin

ICM

R 2

006

• Cutting speed: 270 m/min• Depth of cut: 0.5 mm• Feed: 0.095 mm/rev• Insert nose radius: 0.4 mm• Rake angle: 5°• Air jet pressure (nozzle

inlet): 6 bar• Insert material: WC• Workpiece material:

AISI1020 steel

Experimental ResultsTrinity College Dublin

ICM

R 2

006

• Force

Small reduction of forces, when using air jets


ICM

R 2

006

• Force

• Finishing

Without jet Ra = 0.83μm

With jet Ra = 0.75 μm


ICM

R 2

006

• Force

• Finishing• Chip shape

and colour

Air jet on

Air jet off


ICM

R 2

006

• Force

• Finishing• Chip shape

and colour• Thermo-

CameraAir jet on Air jet off

Finite Element ModelTrinity College Dublin

ICM

R 2

006

• Deform-3D™• Arbitrary Lagragian

Eulerian formulation• adaptive non-linear

remeshing algorithm• fully coupled

thermo-mechanical analysis


ICM

R 2

006


ICM

R 2

006

• Deform-3D™• Arbitrary Lagragian

Eulerian formulation• adaptive non-linear

remeshing algorithm• fully coupled

thermo-mechanical analysis

• Force prediction


ICM

R 2

006

• Femlab3.1™• Frictional power• Estimated specific

cutting energy• Heat transfer by

formed chip• Thermal power

generation in the chip-tool interface area

Conclusions & Further ResearchTrinity College Dublin

ICM

R 2

006

• Heat transfer by impinging jet

1. Fluid-dynamic data

2. Estimated Nusselt number

3. Temperature measurement with hot-spot radiometer


ICM

R 2

006


• Chip shape and shear plane investigation

1. Beneficial effect of the force applied on the chip by the air jet

2. Quick-stop tests


ICM

R 2

006



• Improve the FE modeling

1. Modeling the air jet effect (Deform)

2. Improving the friction model (Deform)

3. Improve heat transfer model in chip-tool interface (Femlab)

4. Develop a fluid-structure interaction model (Femlab)


ICM

R 2

006




• Testing

1. Cutting parameters

2. Workpiece and insert standard materials

3. Air jet positioning

4. Investigating the use of atomized fluids

5. Investigating the use of two nozzles: overhead and flank configuration


ICM

R 2

006




• Testing• Advanced testing

1. Nickel base alloys cutting

2. Other machining applications


ICM

R 2

006

Thank you for the attention

Green Cutting using Supersonic Air Jets as Coolant and Lubricant during Turning Authors Andrea...

Documents

Transcript of Green Cutting using Supersonic Air Jets as Coolant and Lubricant during Turning Authors Andrea...