This is an interesting one, a Danfoss 100mm stop valve installed in a discharge line header close to inlet of condenser.
It was for future line, so it had a stub of pipe & end cap on it, valve closed
When the future work was being carried out, it was found valve would not hold, so pumped out & inspected, this was found.
Appears pressure so great it hydraulic forces destroyed valve.
Valve was put in with direction of flow from header to pipe stub.
Attachment 13957