Thrust bearing for grinding table with associated casing.

Planetary gear stage with internally toothed ring gear.

Bevel gear stage with its own casing.

The gear casing consists of a sturdy welded steel structure.

The fixed ring gear is bolted to the casing so that reliable torque transmission is guaranteed. The grinding pressure including grinding table weight is transmitted straight to the foundation via the tilting-pad thrust bearing and the casing wall.

The motor drives the bevel gear stage via a flexible coupling. The torque is then transmitted to the planetary gear stage via a toothed coupling.

The rotating planet carrier is bolted to the output disc, which supports and drives the grinding table.

The pads of the high-quality tilting-pad thrust bearing for the grinding table are lined with babbitted metal. Their purpose is to absorb the static and dynamic grinding forces. They are lubricated by high and low-pressure pumps (hydrostatically and hydro dynamically). Their temperature is continuously monitored.

The planet shafts are also lined with babbitted metal and scraped. They form hydrodynamic bearings together with the planet wheels.

The principle of Klingeinberg cyclo-palloid gearing is used for the bevel gear stage. The teeth of the spiral bevel wheels are casehardened. A quality level of Q6 or better to DIN 3965 is achieved.

The spur teeth of the sun pinion and the planet wheels are casehardened using the CARBOMAAG method. They are ground on MAAG SE-202 and SE-402 grinding machines, achieving a quality level of Q3 or better to ISO 1328-1.

The tooth flanks of the sun pinion have a profile and longitudinal correction to compensate fully for the deformations of the sun pinion and planet wheels occurring under load. The ring gear is heat-treated. The internal teeth are finished on a MAAG gear-cutting machine with a special gear-cutting tool. A quality level of Q6 or better is achieved.

The gear unit is lubricated by a closed-circuit oil system.

The oil tank services as a platform, on which all the assemblies and components such as motor pumps (high and low pressure), switchable double oil filter, oil cooler and instrument panel with monitoring instruments are installed. The components are amply dimensioned and of the highest quality.

Top priority is given to guaranteeing operational reliability.

MAAG introduced the technology of heavy-duty planetary gear units for the cement industry with great success in 1965.

Experience, new technical findings and the latest manufacturing techniques are utilized in production. A willingness to innovate and close collaboration with our customers has contributed towards the gear units being reliably used throughout the world, under the toughest conditions.

• Fully developed design
• Compact, two-stage design (bevel gear stage/planetary gear stage)
• High quality, reliable, very high efficiency.

The design of the WPU gear unit is optimized to suit the mill power, grinding table speed, motor speed and local conditions.

Full account is taken of customer specifications.

The power transmission of WPU gear units’ ranges from 250 to 9000 kW.

The latest machines and technical aids are used in manufacturing.

Production and all activities are monitored by the internal quality assurance system (certified by Det Norske Veritas) in strict compliance with ISO 9001.

Gear units and the associated lubrication system are tested and recorded in detail on our own test bed prior to delivery.

The compact design simplifies transport and reduces installation time.

Transparency in the progress of work is guaranteed at all times by continuous monitoring of production.

• Customer care is dealt with by trained and skilled staff.
• Maintenance must be performed according to the operating instructions. However, special service contracts are available if customers prefer.
• Spare parts are available throughout the life of the gear units.
• MAAG can be contacted within a very short time thanks to our worldwide network of agents.
• Our skilled service specialists are ready to provide rapid and expert assistance at any time.