Varvel F RD12 Coaxial Gearbox – Output shaft Ø20 x 40 mm

What is the Varvel FRD12 coaxial gearbox with a Ø20 mm shaft?

The Varvel FRD12 is part of the helical coaxial gearbox range from Varvel, a leading Italian manufacturer in industrial power transmission. Designed to reduce the rotational speed of an electric motor while increasing output torque, this model stands out for its Ø20x40 mm solid output shaft, dimensioned to meet the requirements of medium-torque applications.

Its compact and robust design allows it to be installed without constraints in various production environments: conveyors, automated handling systems, packaging machines, process lines, and food processing equipment. The FRD12 benefits from Varvel's historical expertise, whose solutions have been deployed for decades in European and international markets, with a constant commitment to reliability, quiet operation, and long service life in continuous use.

Operating principle of the FRD12 gearbox

The FRD12 utilizes a precision helical gear system that progressively transforms a fast input speed into a controlled output speed, with proportionally increased torque. The helical meshing, specific to Varvel technology, distributes loads over multiple teeth in simultaneous contact, which naturally dampens vibrations, limits noise emissions, and preserves component integrity over time.

The input interface is designed according to IEC standards, allowing direct connection to a standardized electric motor without the need for specific adapters. This design simplifies integration into new installations as well as modernization projects.

Motor compatibility and input flanges

The Varvel FRD12 accepts standardized electric motors with frame sizes IEC 56, IEC 63, IEC 71, IEC 80, and IEC 90, thus offering extensive coverage of the most common motor powers in industry. The connection can be made via either a B5 flange or a B14 flange, depending on space constraints and installation configuration.

For the B5 flange, the standardized flange diameters are Ø120 mm for IEC 56, Ø140 mm for IEC 63, Ø160 mm for IEC 71, Ø200mm for IEC 80 and for IEC 90. For the B14 flange, the face diameters are Ø90 mm for IEC 63, Ø105 mm for IEC 71, Ø120 mm for IEC 80 and Ø140 mm for IEC 90.

The FRD12 also features an internal elastic coupling that dampens starting shocks, tolerates slight misalignments, and protects the entire geared motor against transient overloads. This is a decisive advantage when replacing existing equipment or commissioning a new line.

Available reduction ratios

With 23 reduction ratios, the Varvel FRD12 covers a particularly wide range of applications. The range extends from 2.25 to 63, including the following intermediate values: 2.5 – 2.80 – 3.15 – 3.55 – 4 – 4.5 – 5 – 5.6 – 6.3 – 7.1 – 8 – 9 – 10 – 11.2 – 12.5 – 16 – 20 – 25 – 31.5 – 40 – 50 – 63.

This amplitude allows for precise selection of the appropriate ratio for each process, whether for slow, high-torque drives or moderate-speed applications. Each ratio has been optimized by Varvel engineers to maximize energy efficiency at every operating point.

Ø20x40 mm solid output shaft

The FRD12 in this configuration is equipped with a solid shaft of Ø20 mm diameter and 40 mm bearing length. These dimensions allow for direct mounting of various transmission components—pulleys, sprockets, rigid or elastic couplings—without the need for intermediate connecting parts.

This shaft is dimensioned to withstand significant radial loads and repeated fatigue stresses, common conditions in intensive cycle industrial applications. The machining quality and materials selected by Varvel guarantee optimal mechanical strength throughout the gearbox's lifespan.

Mounting options

The Varvel FRD12 offers two mounting configurations adapted to field constraints. Foot mounting B3 is suitable for installations on chassis or metal frames: the gearbox is laid flat and bolted, ensuring great stability and facilitating maintenance. Front flange mounting, on the other hand, meets configurations where floor space is limited, allowing direct attachment to the machine frame face.

This dual mounting option simplifies both new installation projects and replacement operations on existing equipment, without requiring structural modifications.

Equivalences with other brands

Thanks to strict adherence to IEC standards, the Varvel FRD12 Ø20x40 mm is a direct alternative to many coaxial gearboxes on the market. With standardized dimensions, shaft diameters, and mounting hole patterns, it can replace models from brands such as SEW-Eurodrive, Motovario, Bonfiglioli, Leroy-Somer, or STM, subject to prior verification of mechanical interfaces and availability of the desired reduction ratio.

Technical conclusion

The Varvel FRD12 Ø20x40 mm is a complete coaxial transmission solution, combining versatility, robustness, and ease of integration. Its 23 reduction ratios up to 63, IEC motor compatibility from 56 to 90, two flange types, and two mounting modes make it a gearbox particularly suitable for medium-torque industrial applications. It embodies the level of excellence that Varvel has maintained for decades: durable components, standardized interfaces, and proven reliability in real production conditions.