Parallel Shaft Gearboxes
Parallel-shaft gearboxes are helical gear drives in which the output shaft runs parallel to, but offset from, the input shaft. Torque is transmitted through one or more helical gear stages whose shaft centres lie side by side, so the drive keeps the high efficiency and smooth, quiet meshing of helical gearing while presenting the output low and to the side. That offset geometry suits the unit to side-mounting against a machine frame and to hollow-shaft fitting directly onto a driven shaft, which is why parallel-shaft units dominate conveyor, agitator, extruder and bulk-handling drives.
The family is defined by stage count and mounting rather than by a change of tooth principle. Two- and three-stage trains are common, covering wide ratios, with single-stage reductions near 1.25:1 to 8:1 building to roughly 200:1 and higher across stages. Because every stage is helical, per-stage efficiency is generally high, commonly cited near 96-98 percent, leaving multi-stage units well above 90 percent overall. Load rating follows AGMA 2001/2101 or ISO 6336, with enclosed-drive practice per AGMA 6010 and gear quality to ISO 1328 / AGMA 2015. Foot-mounted, flange-mounted and shaft-mounted (hollow-shaft with torque arm) versions cover most layouts.
Construction uses case-hardened alloy-steel gears, typically 20MnCr5 or 18CrNiMo7-6, with ground or lapped profiles, in cast-iron housings (aluminium on the smallest frames). Bearings are SKF/FAG-equivalent, with shaft seals, drain/breather provision and ISO VG 220/320 mineral or synthetic PAO lubrication.
Hollow output shafts accept keyed bores or keyless shrink-disc fittings; solid shafts and output flanges are alternatives. Inputs take IEC/NEMA motor adapters, servo flanges or free input shafts, and the housing's lateral mounting faces allow several mounting positions. Service factor is selected per AGMA SF.
Himalay's MSME partners manufacture parallel-shaft helical gearboxes and gearmotors with gear-rating to AGMA/ISO 6336, ISO 9001 quality systems, load/efficiency test reports and traceability; CE (Machinery Directive), ATEX/IECEx for hazardous areas, and SABER (Saudi Arabia) coordinated as part of the standard order flow.
