Structural durability validation of bearing girders in marine Diesel engines

The aim is to present the state-of-the-art methodology for structural durability evaluation of marine Diesel engines bearing girders and to describe the responsibility of engine designers, manufacturers and system suppliers. A real example of several engines of the same type, where fatigue cracks arose in certain areas of their bearing girders, has been presented. The extensive investigation revealed the cause of the damage. The proper design was proved by properly implemented state-of-the-art design methods and by experimental verification of calculations in two ships. Quality and test specifications prescribed by the licensor have been found correct. It is concluded that the damage cause was the impermissible quality of worldwide manufacture and improper production repair welding during manufacture.