Dutch Fluid Power Transmission Conference 2017 Flexible-pin planetary gearboxes for industrial applications Jan Vosátka
Wikov at first sight 859 Employees 4 Manufacturing plants 75 Mio USD turnover 10+ Applications 300 120.000 Kg gearbox weight 99+ Years of gearbox experience Self-sufficient in R&D & Heat Treatment & Testing & Measuring Processes 77% Export 1884 Est. 2,8 Meters - profile ground gears The Essence of Engineering - Customized individual solutions - Flexible in design and delivery - Fast gear unit prototyping - Innovative, Efficient, Reliable From single gear to complete drive
Planetary gearboxes in heavy duty applications Shredding Mining Handling Renewables Rubber & Plastics Jacking Mineral processing Sugar
Flexible pin Conventional planetary stage Flexible pin planetary stage
Flexible pin Pros and cons Pros + Safe multi-planetary arrangement + Higher power density + Compact dimensions + Better safety factors and lifetime of Gears and Bearings + Shock load resistence + Proven technology (50+ years) Cons - Higher complexity - Higher price
Case study no. 1 Influence of annulus wheel deformation on planet bearings Deformation of the annulus wheel from the reaction arms Such radial misalignments can t be compensated by floating members Misalignments will be corrected by deflections in the flexible-pins Equal load sharing between the planet bearings Bearing reaction force without flexible pins with flexible pins left planet 142 170 top planet 210 183 right planet 144 170 bottom planet 210 183 load sharing K γ 1.19 1.04 Load sharing improved by 14%
Case study no. 2 Influence of sun wheel tilt on planet bearings Some radial deflections can be compensated by floating member Floating member will tilt and will try to tilt the planets Flexible-pin reduces the additional reaction force to the bearings Reaction moment in bearings for 1 degree tilt in sun gear Conventional Flexible-pin [knm] 172 10.7 Conventional Flexiblepin Bearing load reduced by 94%
Case study no. 3 Influence of manufacturing error on planet bearings Mesh stiffness Flexible-pin stiffness Planet support stiffness [N/mm] Conventional 5,4x10 6 Flexible-pin 0,306x10 6 Reaction force in bearings for planet position error of 0.05mm Conventional Flexible-pin [kn] 270 15.3 Mesh stiffness Bearing load reduced by 94%
Multi-planet arrangement load sharing measurements Load balance between planets K measurement
Multi-planet arrangement load sharing measurements /2 Measured point One planet pass Measured point Load balance between planets K measurement
Typical gear teeth face loading Note: Measured values for 8 planet multi-mw wind turbine gearbox stage Load sharing across the facewidth < 30% (K Hß < 1.30)
Multi-satellite planetary stage torque capacity
Flexible pin case study Case study for single planetary stage conventional (left) vs. Flexible pin (right) comparison Gear ratio 3, various output torque Output torque 100 knm Output torque 1000 knm Output torque 2000 knm 1,150 vs. 690 kg 40% weight reduction 9,700 vs. 5,350 kg 45% weight reduction 19,900 vs. 9,500 kg 52% weight reduction
Orbi-fleX Planetary catalogue gearboxes Case hardened or nitrided annulus gears possible for demanding applications Splash or forced lubrication system Dry sump for higher efficiency as an option Floating medium stage compact dimensions Flexible pin design for high torque stage with optional overload stop feature Lightweight open architecture for conventional stage carriers
Flexible pin hydro-dynamic planet bearings as an option
Case study 1 7MW wind turbine gearbox
Case study 2 270 litre rubber mixer drive
Case study 3 Waste wood shredder
Summary & Conclusions Multi-satellite arrangement boosts power density Flexible-pin ensures excellent load sharing under all conditions Improved load sharing increases reliability Controlled flexibility shows excellent results in high demanding dynamic applications Both CAPEX and OPEX are reduced with the above Do not fight with flexibility, use it!
Thank you for your attention, any questions? Jan Vosatka Group Technical Director jvosatka@wikov.com www.wikov.com