Winch drives boast top torque to size ratios

Edited by the Engineeringtalk editorial team Oct 26, 2004

Brevini has launched two new series of high-efficiency planetary winch drives.

Brevini has launched two new series of high-efficiency planetary winch drives: the compact PWD series for drive applications from 3 to 12t, and the SLW-SCW series for operations requiring line pulls in excess of 12t.

Both types are designed for easy integration into winch drums and offer the ability to work in arduous environments (ie marine) via double sealing and optional epoxy paint finishes.

The planetary design of the PWD and SLW-SLC series units allows engineers to simplify winch arrangements and reduce the overall size and weight of winch assemblies.

The same design, offering modular reduction stages to achieve high levels of torque transmission, also enables users to standardize on one type of winch, which is torque rated FEM M5 for arduous duty operations.

The smaller of the new winch series, the PWD 2100, is offered in two versions, with either hydraulic or universal input.

The hydraulic version is highly compact and convenient, providing the facility for direct fitting of cartridge axial piston motors, either from Brevini sister company SAM Hydraulik, or from other hydraulic motor suppliers with an equivalent product.

The Brevini/SAM package offers the advantage of being a fully assembled system.

It is equipped with its own balancing valve unit, to control a load while it is descending, and also an integrated brake.

The brake is a negative multi-disc unit, with hydraulic opening controlled by the selector valve.

It is interlocked with the balancing valve, to keep the load in position in the event that hydraulic pressure is no longer available.

The alternative universal input version offers users the alternative of external 5in diameter brakes with an associated backstop device, which effectively provides one-way operation by preventing back drive through the unit in hoisting, ensuring better winch control The combination of a universal input and a dedicated adapter set enables this version to accommodate any type of hydraulic motor.

The robust design of the PWD drives means that they are suitable for use with winches which have drum support bearings opposite to the drive side, and also with free hanging or cantilever drums.

In either of these configurations, the PWD units provide smaller spigots for drum fitting, and also higher levels of transmittable torque, due to the facility to fit four or five satellite stages.

Users of the PWD units - and of the higher capacity SLW-SCW series - also benefit from the convenience of drum fitting via bolts from the motor side, and easy, motor-side access to the filling, level and drain plugs.

Finally, the units are protected against adverse environments by "caterpillar" seals, which have been tested over long periods in the demanding marine sector.

Complementing the PWD series in the higher capacity range 12 tons and over, is Brevini's new SLW-SCW series of winch drives.

These units are based on Brevini's new S Series gearboxes, which feature a revolutionary new epicyclic gear design that increases the power available from the unit without affecting the overall weight of the design.

As a result, the S Series provides up to 60% more torque output than other gearbox designs of equivalent size and weight.

The SLW series units employ this unique torque advantage in up to three rotating stages - with a forth, a bevel unit (SCW) planned.

The stages are designed with small spigot diameters to permit easy integration into winch drums that have their support bearings opposite to the drive side.

The SLW-SCW drives are designed for use with hydraulic motor drives and hydraulic brakes.

In addition, a split drive for two smaller motors is being planned, as an electric motor alternative.

Other options include double grease-packed seals and an epoxy paint finish, both designed to provide high levels of protection in arduous and corrosive marine environments.