Piping

This is a small part of the auxiliary steam system of unit EC 20.
In the past the auxiliary steam was produced by it's own auxiliary boiler but that one was completely worn out and was not reliable anymore.

Now the steam is coming from the "new" units by means of a long pipe.
When EC 20 is running it produces it's own auxiliary steam, branched off from a bleed from the main steamturbine (that's the cheapest way).
But when the unit is at standstill it still needs steam for the shaft-sealsystem, feedwatertankheating and central heating.

So when the unit is running, the long steampipe coming from the other building is shut off but has to be kept well above the saturation point, otherwise the steam inside the pipe condenses to water and that's dangerous (waterhammering) when the supply valve is opened again.
That is: when the unit is stopped and cannot supply it's own steam anymore.

So a bit of steam is branched off and sent to the blow downtank to keep a little flow in the pipe.
This is a loss because it goes to the atmosphere. (the pipe that's going down in the picture)
We are planning to lead this small flow back to the unit to use the steam again.
I was looking for the best way to do this, that's why I made this picture as an impression....