Take a look at these pressure gauges. The deformation was caused by
high ambient temperature, the plastic bodies literally melted, as well
as all soft plastic stuff that was around the power pack.
This relatively large power pack, mounted inside a
30ft container, oil capacity of around 1000 lt, was used to power
special hydraulic tools of a large drilling rig, that punched
geothermal wells on Azorean Islands.
The main reason of the overheating was simple and
dumb. The power pack was equipped with oil cooling/filtering system
that used a separate group 3 gear pump to circulate the oil. Two main
electric motors were powered by 600V/60HZ three phase current, and the
circulation pump motor by 380V/50HZ three phase current.
The rig would stay on one site for no more than a
month or two, and then would move to another drilling location. Every
time the container got moved, all the external power connections were
disconnected. The 600V extension cable was always the same, but there
were a whole lot of 380v extensions all over the drilling site, and a
different one was used every time the container moved.
No need to say that there was no established
extension phase order, so each time there was a 50 percent chance the
circulating pump would turn in the wrong direction, which it did for
long periods of time. And here you have it - warm Azorean climate,
closed container, cooling system rendered useless, and the powerpack
working 24/7 - it doesn't get much hotter than that!