Home Foundry

[dazz]

Hi
I looked at siphon-nozzle burners and rejected that option. I would have to buy a compressor (=$$$), which is complex, noisy and takes up space I don't have.
As an energy source, compressed air is expensive (air is free but compressing it is not) and inefficient.
I like the spinning disk burner concept and it would be great if there was a requirement to regulate fuel over a wide range of flows, but I though it would be too complex for a home foundry. It is far easier to make something complex than elegantly simple.

So I have settled on an electric pump (cheap, quiet, simple) and matched spray nozzles. I only need a power cable and a fuel line to connect up to the furnace.

I have operated old 1960s built naval boilers. They used multiple pressure nozzles with fixed flow and swirlers. This is really old tech. I am aware that the combustion process is noisy.

Of course all of my opinions are solidly based on nil foundry experience. I try to learn from the mistakes of others so I don't make them. Conversely, I look to replicate the success of others and claim it as my own.

Dazz

 

[GreenTwin]

So I have settled on an electric pump (cheap, quiet, simple) and matched spray nozzles. I only need a power cable and a fuel line to connect up to the furnace.

I finally took a look at the pump you posted.
I sort of assumed that it was of the automotive fuel pump type that I often see in the US used with foundry fuel tanks, with a low pressure output.
But much to my surprise, it is actually a motor/pump combo that is designed to work with heating nozzles.
I had no idea such a thing was made/available, and have never seen it in the States.

It looks like pressure and flow are adjustable.
For a Suntec, pressure is adjustable via a screw that can be accessed inside the pump housing.
I am going to run my Suntec at a constant 100 psi, because that seems to be standard for a pressure nozzle.
So what that means is that my Suntec will produce about twice the flow I need at 100 psi.
I will shunt the excess fuel flow back to the fuel tank via a bleeder needle valve in the line to the nozzle.

So looking at the specs for the pump, selecting a point on the pressure/flow curve at 0.75 MPa, you would have 109 psi to the nozzle, which would be idea from what I have read.
If I am doing the math conversion correctly, the 0.75 MPa would give you between 11 and 13 liters/hr, or 2.9 to 2.4 gal/hr, which is very close to what I often seen in furnaces (I run about 2.6 gal/hr diesel).
The cut sheet says adjusting pressure is via the relief valve, and I am guessing that means it is like the Suntec, where you set the internal relief valve for the desired pressure, and you get whatever flow that produces.

So I think you will have the same situation I have, where you can just have a return line to the fuel tank, and bleed off any excess fuel flow.
I will look again to see what sort of nozzle adapter you are using.
The Delavan nozzle adapter has an inlet on the end, and an outlet on the side for return fuel flow (in a pressure nozzle configuration).

I have not run a pressure nozzle burner yet either, but I think I understand how they work.
It would seem your small fuel pump would work well, and it is highly efficient from an electrical standpoint too.
My gearpump motor is way oversized.

Typical packaged heating burners I have seen around here have a central motor that drives the integral fan, and also powers the gear pump, and so I probably looked at the motor sizes for the combo units, when really I will not be powering a combustion air fan.

So it makes me wonder if that pump is available in the US, or whether it would be a hard-to-find thing?

I think you have found a good pump, and more importantly a pump specifically designed for exactly what you are going to use it for (I missed that until a minute ago).

So you would use a standard pressure-type nozzle with it.
A siphon nozzle would not work with it (I don't think).

That is very cool.
I think you have found a good combination of equipment there for a pressure-style burner.
If this works for you, I am buying one, if I can find it.

.

 

[GreenTwin]

I look to replicate the success of others and claim it as my own.

LOL, its all good.
Claim away.

Everything I know was either posted online, or posted in an equipment cutsheet.
I can't really claim any original knowledge about oil burners.

I did find a great Audel's book about oil burners from perhaps the 1930-40's?
I guess when they started refining crude oil, many steam plants began to convert from coal to oil-fired.
Oil lamps as I recall have been around for a very long time (thousands of years?).

I have seen some of those Navy boiler burners, and some of them used steam instead of compressed air, so that they could burn very thick and heavy crude oil?

I have seen converted locomotives too.
It is much easier to handle, store, move and use oil than coal, in my opinion (no shoveling of oil).

I sort of absorb everyone else's information, and then generally come up with some sort of hybrid, just as you have done.
When do we get to find out if your new burner works as anticipated?
We can give you a couple of days to get it assembled if you really need that much time (LOL, just kidding of course, we will give you an entire week).

.

 

[GreenTwin]

I don't see the Nippon pump for sale anywhere.

As I understand the Suntec pump operation, you can adjust it between 7 gal/hr at 100 psi, up to 150 psi at 3 gal/hr.
Operating at 100 psi will cause less wear and tear on the pump, and that is supposedly where the nozzle atomizes best.
I will shunt the excess fuel flow back to the tank.

Below is a Beckett schematic that I modified to show how I think my setup will look.
I have a remote combustion air blower (leaf blower), and I don't use electronic ignition.

The diagram assumes that a Delavan adapter with side return opening is being used.

 

[GreenTwin]

Here are some old burner diagrams, I think from a vintage Audel's burner book.

These pages show a single tube to the nozzle, no adapter, and ignition electrodes.

I have never seen anyone use an air cone.
Typically if you choke down the combustion airstream, you increase its velocity to the point where the air/fuel flow strikes the back furnace wall and then climbs up the wall steeply and strikes the lid (this is observable at night with the lid open).

So my thoughts are to try to keep the combustion air velocity as low as possible, and thus probably the reason some commercial furnaces use dual burners at 180 degrees.
I have experimented with dual oil burners at 180 degrees, and the air velocity is 1/2 that of a single tube burner, with the result being a flame coming out of the burners that remains very low in the furnace, which is desirable and far more even a flame than a single burner.
At the time I was operating my dual burners, I didn't have a clue about fuel flow rates or anything else, and so I did not realize the befits of a dual burner arrangement, and went back to a single burner.

So your options may be to unscrew the fitting on the end of your tube, and replace it with a Delavan adapter that has the side return, and screw your nozzle into the adapter.
Or add a tee into the line to the nozzle somewhere, to bleed excess flow back to the fuel tank.

 

[GreenTwin]

Comparing your photo below with the photos above, it would seen you have your electrodes assembled backwards.
The bare wire part of the electrodes would need to be near the end of the nozzle?

And the spin vane looks rather restrictive to air flow to me, as far as operating at 2.5 gal/hr.
I think you would be hard pressed to push enough air through the spin vane to reach iron temperatures.
I have not restrictions at all in my 2.5" burner tube, and there is quite a bit of back pressure on my leaf blower.

The arrangement below does not lend itself to using a Delavan adapter, so perhaps a tee in the pipe at the end of the burner tube away from the furnace? for return fuel flow.

 

[GreenTwin]

I think the Suntec and some other oil pumps have an internal relief valve, to prevent over-pressuring the pump in the case of a clogged nozzle or line.
Here is a video of how that relief valve works, and I think this is how the Suntec allows pressure adjustment from 100 to 150 psi.

 

[dazz]

I had no idea such a thing was made/available, and have never seen it in the States.

The one I purchased is the only one I have seen. Liquid fuel domestic furnaces are not used here.
I purchased mine from aliexpress.com search for VSKX125

So I think you will have the same situation I have, where you can just have a return line to the fuel tank, and bleed off any excess fuel flow.

No, the pump has a built-in return. Single line to the fuel tank, single line to the nozzle.

I will look again to see what sort of nozzle adapter you are using.

This one. Misting Oil Spray Nozzle

So it makes me wonder if that pump is available in the US, or whether it would be a hard-to-find thing?

It doesn't really matter if you buy it from China. Note mine is 230V 50Hz.

So you would use a standard pressure-type nozzle with it.

Yes

A siphon nozzle would not work with it (I don't think).

Yes, No it wouldn't work.

That is very cool.

Oh no !!! I was hoping it would be REALLY hot. Over-inflated ego completely deflated.

I think you have found a good combination of equipment there for a pressure-style burner.
If this works for you, I am buying one, if I can find it.

Phew. Ego fully restored.


Dazz

 

[dazz]

Comparing your photo below with the photos above, it would seen you have your electrodes assembled backwards.
The bare wire part of the electrodes would need to be near the end of the nozzle?

And the spin vane looks rather restrictive to air flow to me, as far as operating at 2.5 gal/hr.
I think you would be hard pressed to push enough air through the spin vane to reach iron temperatures.
I have not restrictions at all in my 2.5" burner tube, and there is quite a bit of back pressure on my leaf blower.

The arrangement below does not lend itself to using a Delavan adapter, so perhaps a tee in the pipe at the end of the burner tube away from the furnace? for return fuel flow.

View attachment 127237

Hi
This is the supply side to the nozzle. The nozzle is pointing down. The igniter electrodes are correctly placed.
A single 6mm Cu tube connects this to the fuel pump outlet.
The only thing I can say about the swirler is that they all look similar for this style.

Dazz

 

[GreenTwin]

If this works, I am buying one, but I still say you may need a tee and a return line to the fuel tank.

.

 

[GreenTwin]

And I read a post today about making thin parts in machinable gray iron.
I have read in several books that iron with high phosphorus should not be used to make engines.

So this guy who made a mini-V8 in gray iron said "I had to use old radiator scrap, which is high in phosphorus, due to its high fluidity".

LOL, so much for never using high-phosphorus iron for engine parts.

.

 

[dazz]

If this works, I am buying one, but I still say you may need a tee and a return line to the fuel tank.

I am going to look really silly if I need one and don't fit it.

Dazz

 

[dazz]

Phosphorous and its effects on Iron

 

[awake]

Here are some old burner diagrams, I think from a vintage Audel's burner book.

These pages show a single tube to the nozzle, no adapter, and ignition electrodes.

I have never seen anyone use an air cone.
Typically if you choke down the combustion airstream, you increase its velocity to the point where the air/fuel flow strikes the back furnace wall and then climbs up the wall steeply and strikes the lid (this is observable at night with the lid open).

So my thoughts are to try to keep the combustion air velocity as low as possible, and thus probably the reason some commercial furnaces use dual burners at 180 degrees.
I have experimented with dual oil burners at 180 degrees, and the air velocity is 1/2 that of a single tube burner, with the result being a flame coming out of the burners that remains very low in the furnace, which is desirable and far more even a flame than a single burner.
At the time I was operating my dual burners, I didn't have a clue about fuel flow rates or anything else, and so I did not realize the befits of a dual burner arrangement, and went back to a single burner.

So your options may be to unscrew the fitting on the end of your tube, and replace it with a Delavan adapter that has the side return, and screw your nozzle into the adapter.
Or add a tee into the line to the nozzle somewhere, to bleed excess flow back to the fuel tank.



View attachment 127234


View attachment 127235


View attachment 127236

What is the title of the book? (Wondering if it is still in copyright, or available on GoogleBooks, or so on ...)

 

[GreenTwin]

Here is the Audel's book.
Looks like I did find it somewhere online (not sure where), since I don't have the physical book (I don't think).
The copyright is 1946/1947/1955.

 

[GreenTwin]

I am going to look really silly if I need one and don't fit it.

Yes, but the only way to learn is to try something, and if it does not work, figure out why.
I have been doing that for years with burners.

.

 

[GreenTwin]

I think I will still avoid any scrap iron that has phosphorus in it.
Not worth the risk of getting defects in engine castings.

I think I can fill thin sections of engine castings by using an oversized runner, generous knife or other gating, and keeping the iron very hot when pouring.

My thin sections are nowhere as near complex as the cores in a V8 cylinder head or block, and so I don't really see needing ultra fluid iron in order to completely fill any mold that I would use.

I wonder if that V8 head could have been cast using only ferrosilicon.
The guy that made the V8 did not really do any scientific comparisons (that I am aware of) on a cylinder head casting with and without ferro/carbon additive, phosphorus, etc., so we don't really know what worked (he probably knows more about this).

The ferrosilicon does make the iron noticeably more fluid, but more than a slight amount can also cause excessive shrinkage and hot tears.
And too much ferro will ruin the metal altogether.

.

 

[dazz]

Hi
Attached is a photo from a seller showing the components I have. It shows how they are connected. There is no return line and no where to put one. It makes for a simple installation. The electric spark igniter is a luxury, but I thought I would try it out.

You can also buy ready made burners in a range of sizes but they are expensive.

 

[GreenTwin]

Looks like they have a wide variety of burners and burner parts.
I wish I had time to go test my pressure-nozzle burner, but I am too busy right now.

You will have to blaze the path through the wilderness for us.

If you look at my marked up Beckett diagram above, I would put a tee fitting at the nozzle tube, and a needle valve as shown, but that is just my guess about what may work.

.

 

[dazz]

If you look at my marked up Beckett diagram above, I would put a tee fitting at the nozzle tube, and a needle valve as shown, but that is just my guess about what may work.

Course adjustment of fuel flow can be done with nozzle size selection
The pump has a screw adjustment for fine control of fuel pressure. There is a spring under a big slotted plug.
I already have a pressure gauge to monitor fuel pressure.

If I fit a sleeve valve to the fan output tube, I will be able to control air flow.

I think that combination will give the control I need over fuel/air flows.
All I need to do is build it and try it.

Dazz