Inline Helical Gearbox
An inline helical gearbox, also called a coaxial helical reducer, transmits torque through helical gear stages whose input and output shafts lie on the same axis. Because the drive runs straight through, the unit is axially compact and mechanically efficient, with the angled helical teeth engaging gradually to give smooth, quiet meshing and good load distribution. It is the workhorse reducer for pumps, fans, conveyors, mixers and general machinery where a straight-line drive layout suits the installation.
Inline units are built as single-, two- or three-stage trains. A single stage typically covers about 1.25:1 to 8:1; two- and three-stage versions reach roughly 200:1 and higher. Per-stage efficiency is generally high, commonly cited near 96-98 percent, so even three-stage units usually stay well above 90 percent overall. Power and torque scale with frame size, from fractional-kW gearmotors up to several hundred kW on the largest industrial frames. Load rating follows AGMA 2001/2101 or ISO 6336, with enclosed-drive practice per AGMA 6010 and gear quality to ISO 1328 / AGMA 2015.
Gears are case-hardened alloy steel (20MnCr5 or 18CrNiMo7-6) with ground or lapped profiles for accuracy and low noise. Housings are cast iron on industrial frames and aluminium on compact gearmotors, running on SKF/FAG-equivalent bearings with shaft seals and ISO VG 220/320 mineral or synthetic PAO lubrication, frequently lifetime-filled on smaller units.
The unit accepts an IEC/NEMA motor adapter, a servo flange or a free input shaft, and outputs a solid keyed shaft or, less commonly than parallel-shaft types, a flange. Foot and B5/B14 flange mounting positions are standard, and service factor is selected per AGMA SF against the duty profile.
Himalay's MSME partners manufacture inline 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.
