Thermal Fluids instead of Steam?

[2043]

Hello Trolls,

I am no expert on anything to with steam and record pressing, a total newbie. My 30+ year career as a piping designer has been with process water, gases, chemicals and waste.
But I've been pondering, Why Steam???

I saw this article about replacing Steam with Thermal liquids and thought it might potentially be useful for record press mold heating/cooling.
https://www.azom.com/article.aspx?ArticleID=20077

Oil as a heating/cooling medium seems to require far less energy and may conduct temperature changes more efficiently at lower pressures.
Like I said, I'm no expert at anything with steam. So maybe I'm missing something??? Aren't we just wanting to heat/cool the mold to specific temperatures at as rapid rate as possible?

Thanks for any input anybody has on this idea.

[Lupu]

Interesting idea. I don’t see any reason why it wouldn’t work, although I’m not an expert regarding the fluids.

Do realize that this is an industry where zero development has occured during the last 40 years or so, the final one being DMM. Everything regarding pressing is 1970s technology tops, if not 1800s.

Maybe the heat transfer fluids were not a common solution yet in the 1970s.

The steamless presses of today from Viryl simply use hot water which is inferior of course. Not sure about the MCS Sironi steamless press (http://www.mcssironi.com/pages/allegro2019.html) but I’m guessing water too.

[2043]

I've been looking at tempered water units, unfortunately they are huge power hogs. The Single G2/65 I'm looking at is 380-415v 200a breaker. Which is attainable, but expensive operating.
Its a great unit because it does heating/cooling all in the same unit. Mokon also sells similar units I had noticed that they also have oil heaters and thought "why not?". The oil heaters operate at the high temperatures at a lower pressure need. I believe therefore not needing as much power. I'm looking into it this week and will share my findings.
Thanks for the comment and MCS link Lupu! I hadn't seen that one before.

[dmills]

The phase change gets you very rapid heating (Steam into a cold heat exchanger will condense and that give up a LOT of energy) which is kind of what is wanted for a fast cycle time, with a thermo fluid you only get the energy from the temperature drop, not the (far greater) energy from the condensation of the gas phase 'fluid'.

The real pain is that you have to cycle the press temperature, and that means heating and then cooling a great deal of metal, and there is no good way to recover the heat from the cooling side of the process.

Lower specific heat capacity press components, and maybe removing the disk at a higher temperature and finishing cooling it outside the press would help by reducing the delta T that a cycle involves.

[Lupu]

We are installing an industrial heat pump to provide the cooling and raising the waste heat temperature to 80 °C required in the district heating network here. We sell the heat to the city.

I have been thinking about replacing steam generator with the industrial heat pump so we could have same unit serving both cycles. The heat pump could go to maximum of 120 °C so with water the cycle time would be slow. Not sure what other fluids one could use with the heat pump. But it’s very efficient in heat recovery to my understanding.

[Lupu]

maybe removing the disk at a higher temperature and finishing cooling it outside the press

This would require the pressing matrices a.k.a. stampers to move with the record while keeping some pressure, right? Otherwise the grooves in the warm compound would not keep their shape, affecting the quality. Too difficult maybe.

I would rather focus on optimizing the heat recovery from the cooling water/fluid.

[dmills]

Just remember that heat pump efficiency drops as delta T increases, and Carnot was a right bastard.

Might be something to be said for lowering the mass that is cycled to lower the energy transferred from the steam to the cold water?
We don't have to use 1970s steels today!

Just thinking I don't actually have a press.

[untitledthe]

Perhaps this topic interest you too; https://www.lathetrolls.com/viewtopic.php?f=10&t=8004&p=52844&hilit=heat+exchange#p52844

[2043]

Thank You all so much for your input! Especially the links to older postings.
I'm getting some quotes from Single and Rokon at the moment and will look at the Regloplas units as well. Since I'll just be starting with a single manual press having the heat/cooling in the same unit will make things much easier. Even if the cycle time is not great. Keeping it simple as possible to learn the process.
What I am hoping is that oil thermal fluids might allow us to use a bit less power to keep the electric bill down a bit.

[Aussie0zborn]

Steam is used to heat the moulds because its fast.
Water is used to cool the moulds because its fast.
Using anything else is a waste of time and money. Anything you save in power with alternative methods will be lost tenfold with low production output.