FLENDER Belt Drives with Extended Housing Surface

In gear-unit construction the best engineering always results in an extreme power density, which regularly goes hand in hand with a high operating temperature. If this condition sets in continuously, it leads to impairment of the lubricating capacity of the oil, damage to the seals and so to increased wear. An optimised gear-unit temperature thus increases the service lives of the system, reduces life-cycle costs and maximises the life of the gear unit.

Cooling systems represent additional risk potential for many mine operators, as frequently there is no water supply available. One part of the solution lies in an extended housing surface, a second and more decisive part in intelligent air conveyance that ensures that the ambient air is guided directly over the housing and over as much of it as possible. Siemens has invested a great deal of development work in the fluid mechanics bound up with this.

In the B3SE series Siemens offers a FLENDER gear unit series that is at home in extreme conditions. To guarantee permanent dissipation of boundary-layer air, highly efficient fans are used here. Specially designed air guide hoods ensure that the air flows evenly over the entire housing. In combination with the optimised surface the best qualifications for outstanding heat regulation.

B3SE gear units are available in 13 construction sizes and can be operated outstandingly as multiple drives for drive applications with very high power requirements.


  • Large selection of 13 sizes with few component variants

  • Highest power density

  • High reliability and operational dependability

  • Dustproof thanks to largely contactless and wear-free labyrinth seals

  • Flanged output shafts enable easier gear-unit fitting combined with a small space requirement

  • High efficiencies

  • Outstanding noise characteristics thanks to ground bevel gears and sound-damping housings and especially high tooth contact ratios

  • IDS (Integrated Drive Systems) for perfect coordination and control

Technical data

Nominal torques

up to 1.400.000 Nm

Transmission ratios

i = 5 ... 450

Power ratings

up to 4.500 kW

Gear stages

2- to 4-stages




Helical and bevel helical gear units