Issues with no bake casting of stainless/duplex? 2

[Hercules28]

Dear all,

I know that duplex, super duplex stainless steels are routinely investment cast.

Is there a specific reason why we won't use a method like no bake? Seems much cheaper.
I can't think of a reason why. surface finish? strength of sand?

Herc

 

[bcd]

The labor cost and time to make a sand casting is less, but this savings is offset by more material, and more machining afterwards when using a sand casting. Also, the amount of scrap material generated when sand casting will be higher. Of course there is the appearance to consider where the investment casting will look better. But economically, if you are getting castings from a place where labor is cheap, investment is the way to go. However, you will be size limited because once the castings get too heavy, the ceramic shells in investment castings are not strong enough to withstand the pressure and sand type castings are necessary.

 

[arunmrao]

Not necessarily true. Large parts are cast by sand casting route as Investment casting is not feasible. Pump and valve parts come readily to my mind .

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