32:1 planetary — torque and stiffness for positioning
The GBX1200321403F is a straight-tooth planetary gearbox with a 32:1 reduction ratio, delivering 260 N.m continuous output torque at 100 rpm and 30 °C, with a peak capability of 416 N.m at the same speed. Torsional rigidity of 13 N.m/arcmin and a maximum backlash of 12 arc-minutes mean this gearbox holds position under varying load — relevant for indexing or servo-driven axes where lost motion shows up as repeatability error.
Efficiency and noise — what the numbers mean on the line
94 % efficiency means roughly 6 % of the input power dissipates as heat inside the housing. For a 260 N.m continuous output at 100 rpm (about 2.7 kW mechanical), that's ~170 W of thermal loss — the black anodised aluminium housing sinks that without external cooling in most duty cycles. 65 dB at 1 m no-load is quiet for a 32:1 straight-tooth planetary — comparable to a small office printer. Straight teeth are inherently noisier than helical, so this figure suggests the housing and bearing preload are well-controlled. The gearbox is lubricated for life, so no oil-change intervals to schedule. Service life is rated at 30000 hours at 100 rpm and 30 °C — about 3.4 years of continuous operation before bearing or gear wear reaches end-of-life.
Sourcing reality — obsolete, quoted to order
Available through independent surplus and broker channels.
Mounting and environmental fit
The shaft output carries an IP54 rating — protected against dust ingress and water splashes at the seal face. The ambient temperature range of -25 to 90 °C covers outdoor enclosures, unheated warehouses, and proximity to hot machinery. External diameter is 120 mm (4.7 in). The C45 steel output shaft handles axial forces up to 2100 N and radial forces up to 1500 N at 100 rpm for the full 30000-hour service life — derate these if running at higher speeds or shorter life targets.