What Are Industrial Gear Reducers and Gearmotors, and What Are They Used For?

What Is a Speed Reducer?

A speed reducer, also known as an industrial gear reducer, is a gear assembly enclosed within a housing that receives rotational motion from a motor at high speed and delivers it at a lower speed, while multiplying the available torque at the output shaft. A gear reducer does not generate power—it transmits and transforms it by reducing RPM and increasing the torque available to drive the load. A gear reducer is sold separately from the motor and is connected using an input flange compatible with the NEMA or IEC standard of the selected electric motor.

What Is a Gearmotor and How Does It Differ from a Gear Reducer?

A gearmotor is an electric motor and a gear reducer integrated into a single, compact assembly, factory-mounted as one unit. The main difference compared to purchasing a gear reducer and motor separately is the installation: a gearmotor is delivered ready to install, eliminating the need to couple and align an external motor with the gear reducer. At BIOSA, we supply both configurations: gear reducers for projects where the customer already has a motor or requires a specific motor-reducer combination, and integrated gearmotors for installations where ease of installation is the priority.

Types of Industrial Gear Reducers

Worm Gear Reducer (NMRV): A compact right-angle design that is cost-effective and easy to install, commonly used in low- to medium-power applications. This is the gear reducer product line offered by GABB IP through BIOSA. Shaft-Mounted Reducer (Shaft Mount or Torque Arm): Mounted directly onto the driven shaft without requiring a separate base, and secured with a torque arm. Dodge introduced this concept with its TXT series in 1949, and it remains a benchmark for conveyor applications. Parallel Shaft or Inline Gear Reducer: Uses spur or helical gears instead of a worm gear, providing higher efficiency and greater torque capacity. Commonly found in the product lines of SEW, Rossi, and Sumitomo for more demanding applications. Bevel Gear Reducer (Right-Angle): Changes the output shaft direction by 90 degrees using bevel gears instead of a worm gear, offering higher efficiency than an NMRV reducer in continuous-duty applications.

How to Choose the Right Gear Reducer or Gearmotor

The selection depends on five basic technical parameters: the required power in HP or kW, the required output torque, the desired output speed in RPM, the required gear reduction ratio between the input and output, and the service factor based on the application's load type. These parameters quickly narrow down the available product families. For example, a conveyor with frequent loaded starts requires a gear reducer with a higher service factor than a fan operating under a uniform load, even if both require similar output torque. When any of these parameters fall outside the standard operating range, it is recommended to consult the BIOSA technical team before purchasing. An undersized gear reducer may fail due to fatigue within weeks, while an oversized unit increases the project cost without providing any real benefit to the power transmission system.

Gear Reducers and Gearmotors Distributed by BIOSA

SEW SEW-EURODRIVE is one of the world's leading gearmotor manufacturers, offering parallel shaft, inline, worm gear, and bevel gear product lines, as well as integrated variable frequency drives. It is BIOSA's preferred brand for technically demanding applications and projects requiring detailed engineering documentation. Dodge (TXT and Tigear) Dodge, now part of RBC Bearings, pioneered the shaft-mounted gear reducer with its TXT series, featuring a patented tapered bushing system for easy installation and removal, in addition to its Tigear worm gear reducer line. It is BIOSA's reference brand for conveyor systems and material handling applications. Rossi Rossi offers a comprehensive range of industrial gear reducers and gearmotors, including parallel shaft, inline, and right-angle configurations for continuous-process and heavy-duty industrial applications, complementing BIOSA's portfolio in the medium- and high-power range. Sumitomo Sumitomo Drive Technologies manufactures high-efficiency, low-vibration gearmotors and gear reducers, with a strong presence throughout Latin America via its distribution network. It is a reliable technical choice for precision and continuous-process applications. GABB IP (NMRV) GABB IP is BIOSA Motion Technologies' proprietary brand of NMRV worm gear reducers, available in sizes 040 through 130, with gear reduction ratios from 5:1 to 100:1, aluminum housings for improved heat dissipation, and NEMA and IEC compatible motor flanges. It is BIOSA's economical solution, with permanent inventory available across all branches.