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Vacant Position: Project and sales engineer, Valparaiso, Indiana
For our subsidiary in Valparaiso Indiana, we are looking for a project and sales engineer who...


New seminars in February 2018 in Valparaiso, Indiana
In February, we offer the following seminars at our location in Valparaiso, Indiana: ...

Examples

Cage failure in drives for mobile equipment

Mangelschmierung
Poor lubrication
In drives for mobile equipment, the high speed tapered roller bearings from the input shaft failed due to cage fracture. The root cause has been insufficient oil quantity that led to overheating, subsequent wear, increased forces between rollers and cage and finally cage collapse.
 

Cage failures in railway gearboxes

Käfigbrüche in Bahngetrieben
Cage damage

In numerous wheelset gearboxes, roller bearing failures due to cage fracture could be observed. Our investigations led to the detection of those operation vibrations which exceeded the cage strength defined by its geometry and material.


Wear in a large industrial gearbox

Getriebeendoskopie
Endoscopy

By means of gearbox endoscopy, extraordinary wear has been detected in a large industrial gearbox. Endoscopy has been arranged because of conspicuous noise during operation. Considering the operational needs, replacement of the affected spherical roller bearings and repair of the gearbox could have been arranged subsequent to endoscopy while minimizing costs due to production loss. Finally, presumed poor lubrication has been verified by means of subsequent visual inspection.


Bearing damage in a gearbox for wind energy converters

Wärmebehandlungsfehler
Shoulder fracture

In the gearbox of a wind energy converter, a planetary gear bearing failed by shoulder fracture of the inner ring. In this case, metallographic investigations led to detection of a fault during heat treatment which caused a severe local brittleness.


Electric discharge in industrial plants

Stromdurchgang
Damage by electricity
In several industrial plants, unexpected bearing fatigue were observed. Our investigations led to the detection of electric discharge which could be traced back to defective insulation.

Poor lubrication in an industrial gearbox

Mangelschmierung
Poor lubrication

In an industrial gearbox, poor lubrication led to the typical wear characteristic on gears and bearings, and finally to bearing failure.


Bearing failures in electric motors

Ermüdungsschaden
Rolling contact fatigue
Several electric drives turned conspicuous after pittings appeared on the rotor ball bearings. The  root cause was determined as excessive tensioning of the housing caused by improper mounting, which led to increased bearing loads, by this to higher temperatures and finally to significant reduction of lifetime.

Tooth foot fracture in an industrial gearbox

Zahnfußbruch
Tooth fracture

In a large size industrial gearbox, tooth foot fracture has been detected at the final stage. As the rootcause, improper contact pattern has been detected which could be traced back to housing deflection. Apart from gearbox endoscopy, visual inspection, fracture face analysis, finite elements simulation has been used in context of investigation of this case.


Tooth flank fatigue in wind energy converter

Zahnflankenermüdung in WEA
Flank fatigue

In the main drive of a wind energy converter gearbox, pitting on gear flanks has been detected. Apart from improper contact pattern, too high grainsize of the material has been detected which resulted in reduced flank strength.


Wear in gearboxes for wind energy converters

Fresser auf Ritzel
Fretting on teeth

Omission of necessary maintenance actions led to significant deterioration of oil quality in the gearboxes of several wind energy converters and thus to both worn gears and failed bearings.


Fracture of torque support rod

Gebrochene Drehmomentstütze
Torque support rod

The fracture of a torque support rod of a wheelset gearbox led to the detection of extraordinary loads which could be traced back to the whole system.


Fracture of bolts

Schwingbruch
Fatigue failure

Based on the fracture faces of several bolts which broke beneath their heads by fatigue, cyclic deformation of the connected parts could be identified as root cause.


Fatigue fracture of a welded shaft

Schwingbruch
Fatigue failure

In an electric multi megawatt drive, the rotor shaft failed due to fatigue fracture. As the root cause, we could identify torsional vibrations which are based on the plant configuration.