CYLINDRICAL WORM GEAR PAIR
CALCULATION REPORT
Order Dware
Project WormGear
Sub project Niemann-Winter Band III
Item Beispiel 3 Page 102
ID worm z_1 = 1
ID gear z_2 = 40
Calculated by André Dewispelaere
Company Dware
On date 23/05/2020

Input bearing points Symbol Unit Worm Wheel
Coordinate bearing point A zA mm 0.00 0.00
Coordinate bearing point B zB mm 450.00 250.00
Coordinate mesh point X zX mm 225.00 125.00
Sweep angle mesh point X φX °.dec 90.0000 -90.0000
Driver is -- -- Worm --
Driver rotation hand -- -- right --
Hand of thread -- -- right --
Bearing type -- -- taper taper
Calculation bearing points Symbol Unit Worm Wheel
Reference diameter d mm 83.20 416.80
Distance A - mesh point X lAX mm 225.00 125.00
Bearing span A-B lAB mm 450.00 250.00
Element is driver -- -- yes no
Worm position -- -- top --
Hand of rotation -- -- right left

Input operating conditions Symbol Unit Worm Wheel
Desired service life Lh h 25000 25000
Service factor ID % 100.00 100.00
Roughness worm flanks Ra1 µm 0.800 --
Kinematic viscosity at 40 °C oil ν40 mm˛/s 320 320
Kinematic viscosity at 50 °C oil ν50 mm˛/s 169 169
Oil type -- -- mineral mineral
Wheel transverse force alternating -- -- no no
Short operation time -- -- no no
Short operation time duration tE min s 0 min 0 s 0 min 0 s
Short shocks duration < 15 s -- -- no no

Calculation of forces Symbol Unit Worm Wheel
Release from standstill Symbol Unit Worm Wheel
Static friction coefficient μzA -- 0.120 0.120
Static friction angle ρzA °.dec 6.8428 6.8428
Gear teeth static efficiency ηzA -- 0.503 0.503
Tangential release force FtA N 5.288 --
Release torque TA N.m 219.97 --
Rotation state Symbol Unit Worm Wheel
Sliding velocity vg m/s 6.59 6.59
Reference friction coefficient μz0 -- 0.016 0.016
Sliding friction coefficient μz -- 0.026 0.026
Sliding friction angle ρz °.dec 1.4954 1.4954
Gear teeth efficiency worm driving ηz -- 0.82 0.82
Gear teeth efficiency gear driving η'z -- 0.79 0.79
Worm gear pair is self jamming -- -- no no
Gearing friction power loss PVz kW 3.960 3.960
Idle run power loss PV0 kW 0.484 0.484
Bearing power loss PVLP kW 0.509 0.509
Total power loss PV kW 4.953 4.953
Global efficiency ηg -- 0.77 0.77
Forces Symbol Unit Worm Wheel
Axial force coefficient μ -- 1 1
Tangential force coefficient ν -- -1 -1
Radial force coefficient ξ -- -1 -1
Normal tooth force Fn kN 23.859 23.859
Transverse tangential tooth force Ft kN -3.367 -21.237
Radial tooth force Fr kN -8.160 -8.160
Axial tooth force Fx kN 21.237 3.367
Reaction forces in bearing A Symbol Unit Worm Wheel
x-Component FxA kN -1.683 10.618
y-Component FyA kN 2.117 -1.274
Resultant force FrA kN 2.705 10.695
Direction of resultant force φrA °.dec 128.4938 -6.8394
Reaction forces in bearing B Symbol Unit Worm Wheel
x-Component FxB kN -1.683 10.618
y-Component FyB kN 6.043 -6.887
Resultant force FrB kN 6.273 12.656
Direction of resultant force φrB °.dec 105.5658 -32.9651
Thrust reaction Symbol Unit Worm Wheel
z-Component or axial thrust FzA,B kN -21.237 -3.367