8:1 planetary stage — torque and thermal limits
The GBX0800080554F is a straight-tooth planetary gearbox in the GBX series, 80 mm housing diameter, with an 8:1 reduction ratio. Continuous output torque is 50 N.m at 100 rpm and 30 °C; maximum output torque reaches 80 N.m at the same speed and temperature, provided the duty cycle allows the gearbox to cool between peak loads. Efficiency is 94 %, meaning 6 % of the input power is lost as heat in the gear mesh and bearings — acceptable for a single-stage planetary, but the thermal path relies on the black anodised aluminium housing radiating to still air. The housing is IP54 at the shaft output, so splash and dust ingress are blocked, but the seal is not rated for washdown or pressurised spray.
Load capacity and bearing life — the numbers that govern fit
Service life is 30 000 hours at 100 rpm and 30 °C — this is the L10 bearing fatigue life under the continuous torque rating. If the application runs above 30 °C or at higher speed, the life derates; the gearbox is lubricated for life, so there is no oil-change interval to extend service. Maximum axial force on the output shaft is 1200 N for a 10 000-hour target, dropping to 900 N if the full 30 000-hour life is required. Maximum radial force, applied at mid-span on the output shaft, is 950 N for 10 000 hours and 650 N for 30 000 hours. These are the constraints that govern belt-drive or overhung-load applications — exceed them and the output bearing race spalls before the gear teeth wear. Torsional rigidity is 6 N.m/arcmin, and maximum torsional backlash is 9 arcmin. For a positioning axis, the 9 arcmin of lost motion at reversal must be absorbed by the servo loop or compensated in the controller — it is not a zero-backlash gearbox.
Obsolete — sourcing through independent channels
Schneider Electric lists the GBX0800080554F as obsolete. The part is available through independent surplus and broker channels; quantities are lot-specific and confirmed at the time of RFQ. No factory support or warranty from the original manufacturer applies. The shaft material is C45 carbon steel, the housing is black anodised aluminium, and the gearbox is lubricated for life — no maintenance provisions exist.