FLENDER Self-Aligning Belt Drives

Not every mine offers enough space for complicated measuring, alignment and installation work. Also the need for specialist personnel to carry out assembly work represents a challenge to many a mine operator. Here, as the worlds only provider to do so, Siemens offers the perfect complete solution.

The patented self-aligning system is the answer to many drive problems, which frequently crop up in confined space conditions of the kind, for example, often encountered under ground.

The B3SA offers flexibility for initial start-up, whether it relates to space conditions, the location or assembly. No special know-how is needed either for modification or disassembly work. The entire drive unit need not be aligned. The motor and the gear unit are firmly linked together via a flange. High production quality also ensures the necessary precise connection to the bell housing. The axial fan, the fan cover and the patented Clever Cooling System ensure outstanding heat dissipation.

With the FLENDER self-aligning system in eight sizes Siemens covers a power range of up to 550 kW.


  • Unique, proven concept with a lot of customer references

  • Elimination of measurement and alignment errors ensures fault-free operation

  • 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 173.000 Nm

Transmission ratios

i = 12,5 ... 400

Power ratings

up to 550 kW

Gear stages

2- to 4-stages




Helical and bevel helical gear units