Stainless steel castings 1

[arunmrao]

I am looking for any particular references or books on liquid metal(sodium) pumps used in spacecrafts. My interest is in understanding the requirements of stainless steel castings used for this application .
Thanks in anticipation.

 

[btrueblood]

You'll have to go back to the 50's and 60's in one of the NASA archives, searching for the SNAP reactor project. Even then, I don't think many of the designs past the initial concept ever contemplated a liquid sodium (or sodium/potassium) coolant. I don't know about Soviet space-based reactor systems, but there may be some information available there. More about the SNAP series is at

http://en.wikipedia.org/wiki/Systems_for_Nuclear_Auxiliary_Power

I'd ask the question (or put a pointer post linking back here) over in the nuclear engineering forum - I think there are terrestrial breeder reactors and similar experimental reactors that are/were designed with liquid sodium coolants.

 

[btrueblood]

Should've made one more search before posting. More info. on the US sodium cooled fast reactor here:

http://en.wikipedia.org/wiki/Sodium-cooled_fast_reactor

 

[EdStainless]

You beat me to it. The fast breeder program was sodium cooled.
Lots of good info on what does not work.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

 

[arunmrao]

Thanks for the references. My purpose of posting was to understand the desirability of castings over machining from rounds. Castings do have their limitations compared to wrought forms. Cost is not a very important consideration for such applications.

Is it the size of the pump,that makes castings the preferred choice or am I missing something ?

Thanks as usual for your time and responses.

 

[EdStainless]

Usually geometry limitations. Making closed shroud impellers by machining is nearly impossible.
With a casting you can make very complex internal 3D geometries.
But if you are only making a few pieces then casting is a long route.
If I needed to make a small number of intricate parts that were only inches in diameter I would look to 3D print the waxes and investment cast them.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

 

[bcd]

Another option which is essentially a very high quality casting is HIP. Hot Isostatic Pressing. There are limits on how large a part you can make, but the material quality is uniform and can be exceptionally good. It is expensive but it can be used to make complex shapes like castings and there is a wide election of materials available.