Compressed air is the least of the worry's when dealing with 1000psi steam. If something does give up the ghost it will not be leaking air or water it will be superheated steam.
The biggest issue I see with they system is that there will be a very high probability of thermal stresses and fatiguing the parts that are seeing the cyclic temperature and pressure. This area of the system is much more likely to fail than the portion of the sytem that stays at 1000psi and 280°C. or the part that stays at low temp and pressure. This goes for your injection molding dies as well. I would expect the three way valves you are showing to be a major issue. Also keep in mind that your low temp circuit will likely be flashing the cooling water to steam as it hits the hot portions of the system. This means you will be dealing with 2 phase flow out of the cooling system and will have to deal with the steam that is generated. How are you keeping the hot side hot? The pressure vessel must be designed and built per the ASME Boiler and Pressure Vessel Code or the applicable code in your area. This may mean it is a pressure vessel or it could be classified as a steam boiler depending on how you are heating it. 1000psi 280°C water is nothing to play with as a hobby. Be very careful with this stuff. For reference I am a pressure vessel engineer by day. CNC tinkerer by night. Good luck and be safe. Jim On 2/8/2017 11:49 AM, Chris Albertson wrote: > The only thing I know about this is that you absolutely need to keep air > out of the system. It all needs to be designed so that trapping air in the > plumbing is impossible. When/if the plumbing bursts having compressed air > inside makes it a lot more dangerous. > > > > On Tue, Feb 7, 2017 at 3:30 PM, Leonardo Marsaglia < > [email protected]> wrote: > >> Hello to all! >> >> I'm in the process of designing and planning a system to rapid >> heating/cooling a mold for plastic injection. The project is still in the >> board so I think it's a good time to ask help from you guys. >> >> I'm trying to make the system as simple as possible so I'll tell you what I >> have in mind and what are my doubts and concerns. So here it is: >> >> A high pressure vessell with resistors is what I'm planning to have as an >> accumulator and heating device. (The vessel should have pressure relief >> valves and maybe a rupture disc). The idea is to reach 1000 PSI (to avoid >> water to start boiling) and 280°C. From what I've been reading the best >> pump for this cases is a gear pump because it can handle better the thermal >> dilatation of the components. >> >> My main concern is, at the inlet of the pump the pressure is going to be >> 1000 PSI, and I have only worked with pumps at atmospheric pressure at the >> inlet side. Is this going to be a problem? The differential pressure at the >> output is intended to be 50 or 100 PSI more than at the inlet just to make >> the water flow through the mold and return to the vessel. There are going >> to be valves to switch between cool and hot water. >> >> Also I may need to consider using special materials on the pump because of >> the corrosion, or may be some additives in the water, but my main concern >> is the rough construction of the system. I'm attaching a little diagram >> with my idea just to start and discuse if it's doable or not. Needless to >> say I'm going to take every safety measure possible with this kind of >> system. >> >> I would be thankful if you can guide me or tell me if this is too >> complicated and dangerous to even give it a try. >> >> Thanks as always! >> -- >> *Leonardo Marsaglia*. >> >> ------------------------------------------------------------ >> ------------------ >> Check out the vibrant tech community on one of the world's most >> engaging tech sites, SlashDot.org! http://sdm.link/slashdot >> _______________________________________________ >> Emc-users mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/emc-users >> >> > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
