47
Prof. HE Ning Green and Energy-efficient Machining Technology Nanjing University of Aeronautics and Astronautics October 23, 2014 Sino-German Forum on Sustainable Manufacturing
Prof. HE Ning
Green and Energy-efficient
Machining Technology
Nanjing University of Aeronautics and Astronautics
October 23, 2014
Sino-German Forum on Sustainable Manufacturing
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Brief Introduction to NUAA
Founding: Nanjing College of Aeronautical Industries
(1952-1956)
Nanjing Aeronautical Institute 1956 - 1993）
1962：Recruiting Postgraduates
1978：National Key University
1981：One of the First Universities Awarding Ph.D degrees
Nanjing University of Aeronautics and
Astronautics（1993 – Now）
1996：National “211” Project University
2000：Establishing “School of Graduate”
2002：Entering the process of becoming Research-oriented
university
History
October 20, 1952
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
NUAA is located in Nanjing, the ancient capital of 10 dynasties with 2500 years history.
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
2
3
4
Outline:
5
Energy efficiency in manufacturing process
Pollution reduction in manufacturing
Ambient air quality in workshop
Issues to be further studied
1 Introduction
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
─ New demand in Manufacturing
Population
Resource
Environment World’s 3
hot issues
New Development pattern in
21 century – Sustainable
Manufacturing
Manufacturing Industry consuming 50
％~60% of total energy，is the main
resource consumption and is one of the
main source of pollution 。
Key problem in manufacturing industry:
--How to make production process at higher efficiency, higher
energy-saving and more environment-friendly.
Introduction
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
[Allen and Shonnard ]
Introduction
cumulative growth in federal environmental laws and amendments
─ Environmental regulations
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Park C-W, Kwon K-S, Kim W-B. Energy consumption reduction technology in Manufacturing - A selective
review of policies, standards, and research. International JPEM, 2009,10(5): 151-173.
─ Comparison of energy use in the manufacturing industry in
several countries and the world overall
Introduction
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
─ Origins of sustainable manufacturing: sustainability
Impacts
Product Complexity
Consumables Workforce
Tools
Facilities Part Precision
Manufacturing
[U.S. energy consumption by sector , EIA 2008]
Introduction
[MED, University of California at Berkeley, 2008]
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
“Sustainable manufacturing
is a platform for
development of innovative
manufacturing technologies
which address world wide
resources shortages and
excess environmental load
to enable an environmentally
benign life cycle.”
[IMS (Intelligent Manufacturing Systems ) MTP, 2009]
─ Definition of Sustainable Manufacturing
Introduction
[Wikipedia Creative Commons - Sustainable
Development , 2009]
Social
Environment Economic
Bearable Equitable
Viable
Sustainable
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
─ Sustainable in total life cycle
Sustainability Integration
Production life-cycle stage Sustainability Principle
Design Materials selection
Materials consumption Government compliance
Manufacturing Process selection
Process optimization
Trasportation Packaging requirements
Shipping efficiency
Use Energy requirements
Maintenance
End-of-Life
Disassembly Remanufacturing
recyclability
Introduction
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
─ Key Technologies of Sustainable Manufacturing
Green and high
energy efficient
machine tools
High
performance
cutting tools
Green and
energy efficient
machining
technology
Sustainable
manufacturing
process
optimization
Introduction
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
─ The sustainable manufacturing
Main concepts:
Low energy consumption
Low materials consumption
Low waste and pollusion (solid, liquid, gas)
Key path: 3R
Reduce
Recycle
Reuse
Introduction
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
2
3
4
Outline:
5
Energy efficiency in manufacturing process
Pollution reduction in manufacturing
Ambient air quality in workshop
Issues to be further studied
1 Introduction
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
─ Energy Consumption Evaluation of Machine Tools
[ITRI, 2009]
Energy efficiency in manufacturing process
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
─ Influence of Machine Tools on Environment
Lifecycle: ①Mfg, ②Use, ③End of LIfe
Machine Tools
Industrial
Products
②≥95%
②≈80%
• Chip
• Waste
• Noise
• Electromagnetic
waves
• Assume one machine tool: Spindle Power 22kW,
Processing time accounted for 57%, Work in two shift.
• Assume one SUV: Driving 19,320km per year, Fuel
consumption 2,194L.
• CO2 – 61 SUV’s
• SO2 – 248 SUV’s
• NOx – 34 SUV’s
[ITRI, 2009] Environmentally Benign Manufacturing (EBM). http://web.mit.edu/ebm/www/index.htm, 2007
Energy efficiency in manufacturing process
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Lifecycle Costs of a machine tool
[PTW, Projekt COSTRA (Life Cycle Costs Transparent), 2006 ]
─ Energy Consumption Evaluation of Machine Tools
Energy efficiency in manufacturing process
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
[Gutowski, T, Dahmus J, Thiriez A.. Electrical Energy Requirements for Manufacturing Processes. 13th
CIRP International Conference on Life Cycle Engineering, Leuven, Belgium, May 31-June 2, 2006. ]
machine center
─ Energy Consumption Evaluation of Machine Tools
automatic milling machine (spindle power: 6.0 kW)
Energy efficiency in manufacturing process
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Source: IWP and IWU
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Energy efficiency in manufacturing process
─ Energy consumption model of machining (UC, Berkeley)
Refer to: Diaz et al. 2011
ecut = k ´1
M .R.R+ b
Specific energy
consumption model
of machine tools
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Energy efficiency in manufacturing process
─ Energy consumption model of machining (University Politehnica
of Bucharest )
Refer to: Draganescu et al. 2003
Specific energy
consumption model of
milling machine
energy
consumption
model
Specific energy consumption model of machine tools based on the response
surface methodology
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Energy efficiency in manufacturing process
─ Energy-saving technologies for machine tools
Light-weighting design
- New structures
- New materials …
Energy consumption monitoring and management
- Automatic energy management
- Monitoring technology of machining process …
Optimization of control and drive
- Optimal utilization of floating process energy
- Energy-efficient motion control and drive technology (VVC)
On demand lubricating and cooling
- Advanced cooling & lubricating methods
- On demand cooling & lubricating supply…
Energy recovery and recycling
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Energy-saving technologies for machining High performance lubricating and cooling
- (cooled) Air jet cooling
- (cryogenic) MQL cooling & lubricating …
Energy efficient machining
- Process optimization for high energy efficient ( specific engergy J/mm3)
- high efficiency machining
Energy efficiency in manufacturing process
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Example of high efficiency mamchining
Comparing in rough machining：
Machining D
(mm)
Z
z
ae
(mm)
ap
(mm)
v
(mm/min)
fz
(mm/z)
time
(min)
volume
(cm3)
Removal R
(cm3/min)
Original Driling 40 4 40 20 40.19 0.03 6.90 221354.23
21.24 Rough milling 30 4 10 20 37.68 0.05 130.73 2702436.1
HFM Rough milling 32 3 22 1.2 80.00 0.70 83.86 2745864.8 32.74
Comparing in finish machining：
Machining D
(mm)
Z
z
ae
(mm)
ap
(mm)
v
(mm/min)
fz
(mm/z)
time
(min)
volume
(mm3)
Removal R
(cm3/min)
Original Finish milling 20 4 1 21 125.60 0.10 26.84 251668.10 9.37
HFM Finish milling 20 4 1 21 126.00 0.15 16.47 268785.62 16.32
+54.14%
+74.17%
High feed milling (HFM)
Examples in Machining Ti6Al4V
It pairs shallow depth of cut with high
feed per tooth which gives higher metal
removal rates by using special miller
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Example of high efficiency mamchining L
imit
de
pth
of cu
t
(mm
) Control of vibration——varying-speed and unequal blade spacing cutter
Varying-speed milling N
O.
A
Amplitude
(Δn/n)
B
Frequenc
y (Hz)
1 10% 0.1
2 30% 0.5
n (r/min)
Milling with unequal blade spacing cutter
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
2
3
4
Outline:
5
Energy efficiency in manufacturing process
Pollution reduction in manufacturing
Ambient air quality in workshop
Issues to be further studied
1 Introduction
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
High cutting temperature
Short tool life/ rapid tool wear
Poor machining surface
Air quality Cooling and lubricating
High performance
cutting tools
High performance
machine tools
Optimized cutting
parameters
cost
High performance
cooling and
lubricating methods
— the best way
─ Problems in metal cutting process
Pollution and emission reduction in manufacturing (CMQL)
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
High efficiency
High quality
Economy
Environment-friendly
Cutting with low temperature air cooling
Cutting with minimum quantity lubrication (MQL)
Cutting with water vapor as coolant and lubricant
Cutting with cryogenic pneumatic mist jet impinging cooling
Cutting with Cryogenic MQL (CMQL)
─ Colling and lubrication technology
Pollution and emission reduction in manufacturing (CMQL)
Page 28
CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
─ Cryogenic Cooling and Lubrication Methods at the PTW and NUAA
Emulsion Dry Cold air Cryogenic methods Compressed air
Cooling strategies used at PTW within Opticut
Cooling & lubrication strategies used at NUAA within Opticut
Decreasing cutting temperatures Increasing heat removal rate
Cryogenic pneumatic mist jet Cryogenic MQL Cryogenic N2 MQL MQL
Decreasing frictional coefficient at tool/chip interface Increasing anti-wear effect of cutting tools
Pollution and emission reduction in manufacturing (CMQL)
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
─ Cryogenic MQL system
pipe spindle Micro-pump
used in low
temperature
refrigeration
Oil mist
mixture nozzle Pre-cooling
and control
system
Compressed air
Power Machine table
principle figure of cryogenic MQL
high efficient heat exchange effect
Single-cycle channel heat
exchange
Pollution and emission reduction in manufacturing (CMQL)
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
0.0 0.1 0.2 0.3 0.4 0.5 0.6
0.0
2.5
5.0
7.5
10.0
12.5
15.0
17.5
刀具磨损率
W (
m/s
)
前刀 面 距 切 削刃 口 的 距 离 (mm)
= 0.4
= 0.5
= 0.6
= 0.7
─ Effect Mechanism of CMQL on Cutting Process
Cryogenic air jet
Cooling Anti-friction / lubrication
•E
nlarge differential in
temperature
•Increase the heat
exchange area
•G
ood enhanced Heat
exchange
Form
lubricating film
Reducing
friction heat
MQL (lubricant)
Cryogenic MQL
Speed field of MQL
Pollution and emission reduction in manufacturing (CMQL)
distance to cutting edge (mm) distance to cutting edge (mm)
too
l w
ea
r ra
te (
μm
/s)
too
l w
ea
r ra
te (
μm
/s)
Cutting tool life
Surface quality
Machining efficiency
Costs
Environment friendly
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Tool life & surface roughness of high speed milling Ti6Al4V alloy at different cutting media (cutting tool：Walter uncoated inserts (WK10). cutting parameters：vc = 400m/min, fz = 0.1mm, ap = 5mm, ae = 1mm)
◎ Titanium alloy
Surface roughness Tool life
Pollution and emission reduction in manufacturing (CMQL)
─ Application of CMQL on HSC of DTCM
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Tool life & surface roughness of high speed cutting Inconel718 at different cutting media
(cutting tool：KC5010 cemented carbide. cutting parameters：vc= 76 m/min, f = 0.1 mm/r, ap= 0.5 mm)
◎ Superalloy Tool life Surface roughness
Pollution and emission reduction in manufacturing (CMQL)
─ Application of CMQL on HSC of DTCM
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Tool life & surface roughness of high speed cutting AISI D2 at dry cutting and cryogenic MQL conditions (cutting
tool: TiAlN coated cemented carbide (k30). parameters: vc= 250 m/min，fz= 0.1 mm，ae= 0.4 mm，ap= 5 mm)
1．Helix angle：30o，Hardness 62HRC，Dry cutting；2．Helix angle：30o，Hardness 62HRC，CMQL
3．Helix angle：50o，Hardness 62HRC，Dry cutting；4．Helix angle：50o，Hardness 62HRC，CMQL
5．Helix angle：30o，Hardness 52HRC，Dry cutting；6．Helix angle：30o，Hardness 52HRC，CMQL
◎ Hardened steel Tool life
Surface roughness
Pollution and emission reduction in manufacturing (CMQL)
─ Application of CMQL on HSC of DTCM
Page 34
CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
◎ Stainless steel
Workpiece material：
PH13-8Mo
Cutting tools：
WSP45, WXM35
Cemented Carbide tool
High speed milling
Tool wear
0 1000 2000 3000 4000 5000 6000 7000 8000 0.00
0.04
0.08
0.12
0.16
0.20
0.24
0.28 vc=180 m/min; ae=1 mm; ap=2 mm
Fla
nk w
ear
VB
(m
m)
Cutting length (mm)
WSP45-air jet fz=0.12mm/z
WSP45-MQL fz=0.12mm/z
WSP45-CMQL fz=0.24mm/z
WXM35-air jet fz=0.12mm/z
WXM35-MQL fz=0.12mm/z
Pollution and emission reduction in manufacturing (CMQL)
─ Application of CMQL on HSC of DTCM
Page 35
CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
xxxx-xx Frame / Material: PH13-8Mo Stainless Steel
Wet Machining CMQL
Total machining time (h) 641 497 ↘22.46%
Total costs of cutting tools
(RMB: yuan) 95070 74506 ↘ 21.63%
yyyy-yy Frame / Material: PH13-8Mo Stainless Steel
Wet Machining CMQL
Total machining time (h) 663 509 ↘23.22%
Total costs of cutting tools
(RMB: yuan) 132581 102925 ↘22.37%
zzzz-zz Beam / Material: PH13-8Mo Stainless Steel
Wet Machining CMQL
Total machining time (h) 639 502 ↘21.44%
Total costs of cutting tools
(RMB: yuan) 71511 56458 ↘21.05%
Total machining time:
≥20%.
Total cost of cutters:
≥20%.
─ Application of CMQL on HSC of DTCM
Pollution and emission reduction in manufacturing (CMQL)
◎ CMQL Milling of Aero Components
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
2
3
4
Outline:
5
Energy efficiency in manufacturing process
Pollution reduction in manufacturing
Ambient air quality in workshop
Issues to be further studied
1 Introduction
Page 37
CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
− Standards of workshop environment quality
Country organization standard
USA
OSHA 5 mg/m3
ACGIH 5 mg/m3
NIOSH 0.5 mg/m3
China SBMBI 5 mg/m3 (inhalation)
UK HSE 5 mg/m3
Japan JOSH 3 mg/m3
Measurement of ambient air quality in workshop
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
CMQL Milling
UCP 710
Machine Tool CMQL
system
Vogel MQL
Handheld Fluke-983
Particle Counter
Measurement of Oil Mist
Particle Size
FA-3 Impact type sampling of powder distribution
OHAUS AR1140
Analytical Balance
Measurement of Oil Mist
Concentration
Data Processing and Analyzing
Measurement of ambient air quality in workshop
− Testing system for the ambient air quality in workshop
– Sampling
time >2h，
– cutting
time>90min
Page 39
CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
− Influence of MQL System Parameters on Ambient Air Quality in
MQL Milling Process
Measurement of ambient air quality in workshop
Oil Flow Rate
（P=0.6MPa，L=20mm，room temperature，oil: B）
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
− Influence of MQL System Parameters on Ambient Air Quality in
MQL Milling Process
Measurement of ambient air quality in workshop
Air Pressure
（Q=15ml，L=20mm，room temperature，oil: B）
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
− Influence of MQL System Parameters on Ambient Air Quality in
MQL Milling Process
Measurement of ambient air quality in workshop
Spray Distance to Target
（Q=15ml，P=0.6MPa，room temperature，oil: B）
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
− Influence of MQL System Parameters on Ambient Air Quality in
MQL Milling Process
Measurement of ambient air quality in workshop
66% 55%
42% 46%
MQL CMQL
Influence of oil volune
42% 46% 48% 56%
Viscosity:10 mm2/s Pour point: -12℃
Viscosity: 22mm2/s Pour point: -24℃
Influence of viscosity
Volume and viscosity of oil
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Coolant MQL CMQL MQL CMQL Coolant
Outside of Machine Tools Inside of Machine Tools
− Influence of MQL System Parameters on Ambient Air Quality in
MQL Milling Process
Measurement of ambient air quality in workshop
Inside and outside machinine tools
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CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
− Influence of MQL System Parameters on Ambient Air Quality in
MQL Milling Process
Measurement of ambient air quality in workshop
No. MQL Parameters & others Influence on Ambient Air Quality
1 Oil Flow Rate ▲▲▲▲▲
2 Air Pressure ▲▲▲▲
3 Spray Distance to Target ▲▲
4 Jet Temperature ▲▲
5 Lubricant Property ▲▲▲
6 Air humidity ▲▲▲▲▲
Page 45
CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
2
3
4
Outline:
5
Energy efficiency in manufacturing process
Pollution and emission reduction in manufacturing
Ambient air quality in workshop
Issues to be further studied
1 Introduction
Page 46
CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Issues to be further studied
Huge amount energy comsumption during production process
Much efforts should be concentrated in developing sustainable
manufacturing process
Holistic technology for sustainable manufacturing process to reduce
energy consumption, to reduce materials consumption and to reduce
waste and pollution
High performance machining with process optimization for
high energy efficient ( specific engergy J/mm3)
Page 47
CMEE, Nanjing University of Aeronautics and Astronautics/ Prof. N.He /Karlsruhe-Darmstadt, Germany, Agu. 4-8, 2014
Thanks！
Prof. He Ning PH. D
Professor of College of Mechanical and Electrical Eng.
Dean of college of International Education
Nanjing University of Aeronautics & Astronautics
Zip：210016
Tel: 86-13305189023
Fax: 86-25-84892256
E-Mail: [email protected]
