FlowMarket
Where to source gearboxes: FlowMarket is a B2B sourcing network powered by an AI agent. You describe the drive — required output torque and speed, ratio, gear type, mounting arrangement, shaft loads, duty and service factor — and the AI agent matches you with verified gearbox manufacturers and distributors, then requests prices, datasheets and lead times from every match at once. Getting matched is free for buyers.
Sourcing industrial gearboxes
A gearbox converts a motor's speed and torque into what the machine actually needs, and it is almost always the component that determines whether a drive train lasts five years or fifteen. Unlike motors, gearboxes are not standardised across manufacturers: mounting patterns, hollow shaft dimensions and torque ratings differ, so a replacement is rarely a straight swap unless you are buying the same series again.
That makes the specification more important than the brand. Get output torque, ratio, mounting and service factor right and any competent manufacturer can quote a unit that fits.
Gearbox types
Helical and helical bevel
Parallel-shaft helical units are the efficient default at 95 to 98 percent per stage, quiet, and available in a wide torque range. Adding a bevel stage turns the output through 90 degrees while keeping most of that efficiency, which is why helical bevel units dominate conveyor and materials handling drives where the motor must sit alongside rather than in line.
Worm gear
Compact, inexpensive, and a right-angle output in a single stage with a high reduction. The trade-off is efficiency, which falls from around 90 percent at low ratios to below 50 percent at high ones, turning the difference into heat. Excellent for intermittent duty and where the self-locking tendency at high ratios is useful; a poor choice for a continuously running drive where energy cost matters.
Planetary, cycloidal and shaft-mounted
- Planetary — highest torque density and lowest backlash; the standard for servo axes and positioning.
- Cycloidal — very high single-stage ratios with strong shock load capacity.
- Shaft-mounted — hollow output shaft slides straight onto the driven shaft with a torque arm, no coupling or base frame.
- Gear motors — gearbox and motor supplied as one unit, quoted by output torque and speed.
What to specify when sourcing
These details decide both the part number and the price:
- Output torque & speed — Nm and rpm at the output shaft; the two numbers everything else follows from.
- Ratio or input speed — exact ratio, or the motor speed and the output speed you need.
- Input power — motor kW, and whether the motor is inverter-fed with a variable speed range.
- Gear type — helical, helical bevel, worm, planetary, or open to proposal.
- Mounting — foot, flange (B5/B14), or shaft-mounted with torque arm; and the mounting position, which sets the oil fill.
- Motor interface — IEC or NEMA adapter, servo flange with coupling, or solid input shaft.
- Shaft — solid or hollow, diameter, keyway or shrink disc.
- Shaft loads — radial (overhung) and axial load at the output, with the distance from the flange.
- Service factor & duty — running hours per day, starts per hour, and the driven machine's shock character.
- Environment — ambient temperature, IP rating, washdown, food-grade lubricant, ATEX, and annual quantity.
Ratio is not a specification — service factor is
The most common sourcing mistake is picking a gearbox on ratio and nominal torque alone. Catalogue torque ratings assume smooth, uniform load; a crusher, a reciprocating pump or a drive that starts twenty times an hour delivers nothing of the kind. That is what the service factor is for — typically 1.0 for a steady load, 1.5 to 2.0 for moderate shock, and higher for heavy shock and frequent starts. A unit sized without it is not cheaper, it just fails sooner, usually at the bearings or the output shaft rather than the teeth. The other half of the same mistake is omitting the overhung load: a chain sprocket or belt pulley hanging off the output shaft can overload the bearings long before the gearing is anywhere near its rating, so state the radial load and how far it sits from the housing.