Science of Friction. DuPont Market Driven Innovation: Volker Plehn. Director Development & Sales. DuPont Kalrez & Vespel

Transcription

1 DuPont Market Driven Innovation: Science of Friction Volker Plehn Director Development & Sales DuPont Kalrez & Vespel

2 Science of Friction Increased Importance of Friction Friction from a Polymer Point of View Examples of Value Chain Co-operation Summary

3 Transportation Megatrends Petroleum consumption Green House Gas emissions Innovation programs Fuel efficiency / emissions Performance New propulsion (hybrids) Increasing use of electronic controls New wear and friction demands Increased need for thermal isolation Applications Variable valve timing & lift Turbochargers EGR technologies New transmission designs (6-8 speeds, CVT, electric/hybrid) Actuators, DC drives, stability systems, electric pumps (fuel, oil, etc.) New materials

4 Transportation Technology Drivers % of energy in fuel available at wheels? 15% 6 out of 7 liters wasted % of energy lost to friction between rotating or moving parts? 10% Over 2,000,000 barrels / DAY Improve efficiency of current devices + Unprecedented # of new technologies! Controlling Friction

5 Friction Control Polymers, fillers & processes for wear & friction solutions High Dry Friction Delrin acetal + PTFE Zytel nylon + PTFE Teflon PTFE brake pads + Kevlar fibers Teflon FEP + Kevlar fibers Teflon ETFE 2X-4X improved wear Vespel TP polyimide Vespel S polyimide Low Performance (e.g.: temp & wear) High Increased need for friction control - especially lubricated friction.

6 Science of Friction: Reducing Energy Loss High Friction Boundary Mixed Hydrodynamic Metal disc P V Lubricant Polymer ring Low Oil Viscosity x Speed (V) / Load (P) Variables to Material control Design friction Temperature T Experimental Results on Seal Rings & Thrust Washers

7 Material Optimization: DuPont Vespel SP-2515 to improve component efficiency. Coefficient of Friction C oefficient of friction o C 23 o C 55% Reduction 45% Reduction Thrust Washer Test equipment Mating material Sample ring Thrust load ATF D-III 0 Vespel SP-2515 PEEK PEEK Vespel SP-2515 PEEK PEEK Revolution For more data and technical paper visit: tryvespel.dupont.com

8 Material + Design = Improved Energy Efficiency Higher PV capability allows less contact area & less frictional loss. Optimized oil groove design expands low friction hydrodynamic zone. Rectangular 0.6mm T Type Oil Pressure Frictional Loss (N-m/ring) % Housing RPM PEEK Vespel T-Type: Vespel 13% % PEEK Vespel w/ optimized oil grooves Groove Surface Temperature ( C)

9 Temperature & Friction Coefficient of Friction * Thrust washer test results 195* 195* Coefficient of Friction Surface Temperature *safety interlock at 195 C Lowest > 30% observed lower surface temperature temperatures Vespel SP-2515 Observations: 4 X higher THERMAL CONDUCTIVITY than many polymers 0 Bronze PEEK CF+PTFE +graphite PEEK 30% CF PAI Low wear PAI SP-21 SP PTFE +graphite 0

10 Thermal Conductivity Thrust Washer (test sample) Oil In New test protocol developed Rotation (V) Support Plates w/ thermocouple Insulating Plate Load (P) Heat flow Coefficient of Friction -> Lower operating temperature -> Lower Friction

11 Thrust Washer Magna Powertrain Vespel SP-21 thrust washer Low wear Broad Temperature range Stable in transmission oils

12 Seal Ring ZF Getriebe Vespel SP-21 Seal Ring Assembly cost savings Lighter weight Maintenance-free operation

13 FRICTION CONTROL in Hot, Dirty environments? Emission Systems Turbochargers Higher TEMPERATURES Potential for CONTAMINATION Increased USE OF ALUMINUM (light weight)

14 Theory: Wear or contamination particles embed into Vespel parts, remaining below the wear surface and protecting mating parts. Metal Substrate (A6061-T5): Longer Life Contamination remains on surface oil Contamination Particles on Surface (note groove formation) Vespel SP Contamination embeds below surface oil Embedded Contamination Particle (note lack of wear groove formation)

15 Wear Resistance Wear Volume (mm 3 ) Intentionally introduced particles (~14 μm) Clean Oil With Particles Vespel SP-21 Vespel SP-2515 PEEK Vespel SP-2515 exhibits 65% less wear

16 Emission Systems EGR (exhaust gas recirculation) Valves Bypass Valves Control Arms & Cams Pintel & Shaft Guide Bushings Actuation Cams or Slides Benefits Repeatable, consistent operation Longer life

17 Turbo Charger Shaft oil seal rings Shaft spacers Linkage & control arm rod ends Spherical bushings Benefits Repeatable, consistent operation Close tolerances: thermal expansion close to aluminum, stainless & cast iron. Good wear against metal surfaces

18 Efficiency Improvements & Reduced Total System Cost 1. Direct: lower friction in rotating components 2. Indirect: better control of fluids and leak rates = lower parasitic losses (e.g.: smaller pumps) 3. Mass: ability to run directly against aluminum housings or shafts reduces system mass and start/stop losses. 4. Cost: improved assembly techniques (e.g.: no need for steel inserts) and longer life drives out costs.

19 Summary Hotter Temperatures Higher PV Higher Torque Smaller Packaging Component Life / Wear DuPont Vespel DELIVERING BIG SCIENCE, PART BY PART. FASTER THAN EVER BEFORE... Additional information at www. tryvespel.dupont.com

20 The information set forth herein is furnished free of charge and is based on technical data that DuPont believes to be reliable and falls within the normal range of properties. It is intended for use by persons having technical skill, at their own discretion and risk. This data should not be used to establish specification limits nor used alone as the basis of design. Handling precaution information is given with the understanding that those using it will satisfy themselves that their particular conditions of use present no health or safety hazards. Since conditions of product use and disposal are outside our control, we make no warranties, express or implied, and assume no liability in connection with any use of this information. As with any product, evaluation under end-use conditions prior to specification is essential. Nothing herein is to be taken as a license to operate or a recommendation to infringe on patents. Caution: Do not use in medical applications involving permanent implantation in the human body. For other medical applications, discuss with your DuPont customer service representative and read Medical Caution Statement H The DuPont Oval logo, DuPont, The miracles of science, Delrin, Kevlar, Kalrez, Teflon, Vespel, Zytel are registered trademarks of E.I. dupont de Nemours or its affiliates. Copyright 2010