Everybody, who worked with hydraulic pumps and motors in the beginning of this century, knows what a Sauer Danfoss series 20 pump looks like. This is an old school design, which existed for decades, and is becoming a rare sight theses days. There used to be a factory in Europe that had a copy of this series in production in 2010, but I am not sure if they still do it today (2018).
In any case - throughout the years these pumps have proven to be "bullet-proof", WHEN at least a modest amount of preventive maintenance is involved. However, when a pump hits 20000 hours of continuous service unspoiled by annoying service stops, surprises like the one you see on these pictures are to be expected.
The fact that the main shaft split in two pieces without doing any but thermal damage to the charge pump shaft is just astonishing.
My favourite picture of this lot is definitely the one showing fine details of those severely bashed piston heads.