Oil Furnace swirl experiments

Mark,

If you can get (or make) coal about the granularity of coarse table salt, that should do as an additive to sand. I could even envision your own “ball mill” should you need to make “sea coal.” A few 3” to 4” iron cannon balls, a common small cement mixer, and a bag of farrier’s coal should do. Messy job though.

The toner might be fine as a dusted-on mold conditioner. But the styrene is an unknown with respect to plugging intragranular pores in the sand. Just have to try it and see, I guess.

Denis

 

Come to think of it, toner's going to form an airtight layer if sprayed on thick and melted with hot air, I'd have to scratch a few air vent grooves at the top, it may be ok with a few percent in place of coal dust mixed with green sand. One of the products my foundry expert made castings for was a small 1Hp flour mill for homesteads and doomsday preppers: it'd be perfect to grind coal and I have a few buckets of "peanut" coking coal used for power stations.

 

Too bad your so far away. I've got plenty. Go to a mom and pop print shop and tell them what you're doing. They'll probably oblige. But I have to wonder if such a thin coating would be enough to do the job.
Now that I think of it there aren't many safety warnings on toner, but "do not burn" is one of them.
Pete

 

Hmm looks like styrene gas, carbon monoxide and hydrogen cyanide are the combustion products, probably not the sort of thing you want to breathe if you're alive and want to stay that way. Ahh well that's an experiment I can do without, coal dust it is!.


After a spot of early morning fettling on the belt grinder (who doesn't love a good fettle first thing?).







It looks like a bifilm defect in the middle but it's burnt sand stuck to the iron.

 

Mark awesome video! And it looks like you had a pretty perfect part in the end!

You mentioned you dial down the fuel to 22 L/h (or 5.8 g/h or 62 minutes) for a 15 kg pour/melt. So you melted 40% more metal with 15% less fuel. This is awesome!

What size is your exhaust diameter?
What what are your internal furnace sizes?
What is your refractory rated at?
You already mentioned you have a 4.5“/114mm tuyere.

I know your combustion air (the size and hp of your blower) and fuel delivery capability (25 L in 10 minutes or 150 L/h or 40g/h)... your furnace could be four-five times the size, and melting 50-100kg of cast iron in two hours.

You have some crazy numbers for Max out. I hope you’re refractory can handle it.

There might some BTU experts here that can give more information on longevity of crucibles and refractory, then I.

I didn’t wanna say this... , but I think you have a Corvette engine in a punch buggy.

 

Hi Matt, here's the furnace dimensions, it was originally shoehorned into a single beer keg but is now: 1.5 beer kegs in height.
Chamber bore is 11"/ 280mm.
Chamber depth of 13.75"/ 350mm from the top of the plinth and refractory disc.
Chamber floor is 20"/ 508mm.
Edit: lid hole is 5" or 125mm

The tuyere is made from 100mm diameter stainless tube with a short section of the diameter widened to allow the 100mm tube to neatly fit inside.

Refractory is 1650 deg C operating temperature.

There seems to be an upper limit to fuel and airflow where complete combustion occurs and exceeding that limit causes unburnt fuel to exit the chamber, if the chamber was a tight seal some supercharging from the high pressure blower could overcome this. Higher burn rates allow casting of copper nickel alloys like monel with their higher melting points in theory.

There is also some more detail in the "Yet Another Beer Keg Furnace" thread of this topic channel.

 

Also forgot to mention: the fuel system is 8 x 3 litre garden mist nozzles fed with 60 PSI fuel: it won't go above 30 litres per hour unless I add some more nozzles.

 

Mark, thank you very much for the clarification. In your first post this stuck in my head.

 

WOW! Iron is really tough on a furnace!

 

I could have phrased that better: "The fuel consumption was 25 litres or about 6 US gallons for a short ten minute run and then 56 minutes continuous" to "The fuel consumption was 25 litres or about 6 US gallons for 66 minutes over two runs, a short ten minute run and a 56 minute run."

Iron oxide is a bit of a pain in the butt, it's fluid enough to move around when hot and stick to everything but it's not too bad....yet. Most of that oxide is from the steel disc experiment where the disc burned and sprayed oxide everywhere up the wall. I did give a few thick blobs a hit with the angle grinder and the concrete underneath was more or less ok. It did eat into it a bit and soak into the cracks to leave a white refractory with a fine black pattern in the cracks sort of like mud in a dried pond. Peter's similar furnace has a thick identical coating from bronze and gold fluxes, I asked him when he last relined the walls and he said sometime in the early 1990's although the bottom is done roughly once a year as the plinth crumbles.