Inside View of Frame Breakage

Rahmenbruch | Frame Breakage in 2014

After return from Scotland MAN maintenance was due. For more information on the trip see:

Surprise: Almost total frame breakage at the right cabin bearing and and bent frame left.

Another Frame Breakage
Another Frame Breakage but now at the rear Cabin Bearing

Analysis showed that breakage had been caused by extreme frame torsion. Longitudinal roll travel of is high under extreme conditions.  UNICAT design allows insertion of extreme frame torsion usinf the frame structure as spring-damping unit. Standard frame structure, however, is unable to disperse forces over the total length of the frame resulting in local overload including bending and breaking.

Simple bearing plates, lack of longitudinal enforcement of the frame  structure, and of stiffening girders between right and left cabin  bearings lead to breakage under extreme conditions together with fatigue. A typical design and fatigue fault.

Inside View of Frame Breakage
Inside View of Frame Breakage

Again, the frame was repaired in Düsseldorf. Both frames, right and left, were cut out, welded and reenforced inside and outside.

Cabin Bearing and Swallow Tails
Welded Frame
Cabin Bearing and Swallow Tails outside during Repair

Swallow tailed steel plates  induce torsion over extended frame length. In addition dampers were renewed.

Swallow Tailed Enforcement of Frame Structure
Swallow Tailed Reinfnforcement of inside Frame Structure
At Work in Düsseldorf | Germany

All measures taken were designed and mounted by the owner, manufacturing was made by professional companies. The maker UNICAT was not involved.

For more information about works, companies and cost, please  contact the site.