Saturday, February 2, 2013

Quick notes on the Fluids subsystem

    So I sent out an email to David Herbet recently detailing a preliminary parts list for the liquid subsystem. I'll post the entire list later on. For now, lets talk about pressure vessels.

   Alfred needs 5 containers/ pressure vessels to hold the different kinds of soda. These need to be about 2 Liters in volume. Google searching hasn't returned any pressure vessels of this size...at least not any cheap ones. PVC was the first material we considered for building drink containers. Pressure within the containers shouldn't be very high (~30psia, if that) when Alfred is running full stop.

   Schedule 80 would be more than able to handle this pressure. From Harvel's website, schedule 80 is used for potable water systems and is resistant to most acids, bases, salts and aliphatic solutions, so it wouldn't react poorly when in contact with the soda. This seems like it would fit our needs....I haven't checked pricing yet though. McMaster Carr also sells schedule 80. 
http://www.harvel.com/technical-support-center/product-specifications/pvc-pipe-schedule-80

  Jordan recommended looking into sheets of stainless steel or aluminum to replace the PVC. It would be bent and welded to create the size pressure vessel we want. I'll have to figure out what size thickness of stainless steel we'll need to avoid having a blowout once we pump them full of pressure. I also need to figure out how to hold carbonation in the soda.

Concerns:

  • How to hold the carbonation into the soda
  • PVC or metal (aluminum, stainless steel, etc)
  • Sterilize the pressure vessels? 
  • NSF and ASTM materials 
That's all for now

No comments:

Post a Comment