FAG Current insulated bearings for traction motor

FAG Current insulated bearings can prevent the effect of stray current. Insulated bearing combines bearing function and insulation performance in the solution, so it is more cost-effective than other insulation methods.

With a unique coating process, a layer of aluminum oxide is coated on the surface of the inner or outer ring of the bearing, so that it has the insulation ability and is not affected by high temperature, moisture and chemicals. The performance and running accuracy of the bearing are the same as that of the standard uninsulated bearing, and no additional installation measures are required.

Technical data

Car unit

Wheel arrangement Bo’2’Bo’

Traction adhesion 65 %

Track gauge 1,000 mm

Distance between wheel pairs 1,800 mm

Vehicle length over buffers 31,480 mm

Max. weight when full 56 t.

Max. axle load 8.3 t.

Max. speed 60 km/h

Wheel diameter (new/worn off) 600/520 mm

Min. track radius14.5 m

Floor height 300 mm

Low floor component 100 %

Traction motor

Traction motors 4 x 100 Kw

(nominal operating point)

Max. speed 4000 min-1

Traction motor inverters 2 IGBT pulse

width modulated inverters

Gear ratio 5.4444

Bearing arrangement

The traction motors are equipped with an FAG NU215E.TVP2.J20A insulated cylindrical roller bearing at the drive end (floating bearing) and an FAG 6215M.C3.J20A insulated deep groove ball bearing at the opposite end (locating bearing).

Both bearings are protected against damage from current sparkover by an oxide ceramic coating (> 0.2 mm thick).

Bearing life The traction motor bearings were designed for a theoretical mileage of more than 2 million kilometers. Drive unit The Combino drive unit consists of: motor, brake disk, spring-loaded brake, motor-gear coupling, bevel gearing, quill shaft, wheel-gear coupling. Each wheel is driven via a quill shaft with two rubbermetal couplings. Current insulation/coating, in general Current insulated bearings prevent damage from current sparkover in the event of potential gradients between the rotor and stator of an electric motor. The oxide ceramic coating, which was applied by means of plasma spraying, features a hardness of > 2000 HV. It is wear-resistant and a good heat conductor. With the J20A coating, the disruptive voltage with direct current is > 1000 V