Remember too, that if this machine is used for any other product, then changing moulds is going to be a nightmare. There's often water slopping about during a tool change.
On 9 February 2017 at 17:22, dave <[email protected]> wrote: > http://www.dow.com/heattrans/products/synthetic/syltherm.htm > > A service of 10 yrs at 400 C is not to be sniffed at. Probably priced > like gold tho. > HTH > > Dave > > On 02/08/2017 06:44 PM, Dave Cole wrote: > > You don't want to use steam at 1000 psi unless you absolutely have to. > > I've gotten in the way of steam at high pressure and that is something > > that you will never forget. At 1000 psi that is an injection hazard. > > High pressure steam leaks can be invisible, and sometime inaudible, so > > you might never see or hear them before it is too late. > > > > Use a different thermal transfer fluid and save yourself the pain, > > literally. > > > > Most of the plastic injection machines I have seen use machines called > > Thermolaters and they circulate a heating liquid to preheat the dies. > > > > Here they are: > > http://www.conairgroup.com/products/heat-transfer/#page=tab-1 > > > > I thought they were mostly using Ethylene Glycol (common Car > > Antifreeze?) as heat transfer fluid. Or perhaps a mix of water and > > Ethylene Glycol. Ethylene Glycol boils at 387 F. > > > > Dave > > > > On 2/7/2017 6:30 PM, Leonardo Marsaglia 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! > >> > >> > >> ------------------------------------------------------------ > ------------------ > >> 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 > > > ------------------------------------------------------------ > ------------------ > 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
