SpudFiles

Im making an oil burner and dont want to buy or make an oil pump. I could make a babington burner but dont want it to run off a compressor.

But i do have a very small fridge compressor so im wondering if i can use it as an oil pump, i know that a fridge compressor is a diaphragm pump and a diaphragm pup should easily be able to pump viscous liquids.



I have attatched an image showing three ideas of how a fridge compressor looks likes inside, im thinking they work on either B or C because if i turn my compressor upside down oil comes out of it.

Has anyone chopped one of these up before because i dont have one to waste. It would be great if they worked like A then i could use the body as an oil tank.

i cut one up and its like none

its closest to b but oil only covers up the bottom 2inches of the case.

its also a piston pump not a diaphram.
and will the oil that your gonna pump be a good enough lubricant to work with the pump?

Its either a piston or a scroll compressor. Also the oil, as stated is inside the bottom part of the housing, the entire housing is presureized. If you use oil it will most probably flood the compressor housing and mix witht he already existing oil, and then get pumped out. So at the begining you will get two different kinds of oil being pumped out. I think it should work but you would have very high pressure, depending on the size of the burner.

Out of curiousity, what will your oil burner be used for, a foundry, a heater, a steam engine boiler or something totally different.

I am thinking about building an oil burner for a water heating system in a pool. The design will be gravity fed, and i recomend that option if you are able to.

Well i decided to cut the top off mine and yes mine is a piston pump not a diaphragm like i expected, mine works like C in my pictures. I tried pumping oil with it and it kept cutting out, there is a circuit breaker on the winding of the coils, also i would have to add a gearbox which is no problem, here are some pictures.

Also my oilburner will be used for a foundry and maybe steam production for a generator. I was going to make a drip-feed one but they take a while to start up plus i need to buy some more refractory mix. I was going to go for a babington burner but dont have a compressor and this one is too small.
So im going for the most compact design, the oil pump pressurises oil up to 100psi and sends it through a jet to atomize it and then through a spark gap. The pump will be sat in the bottom of an oil reservoir, i suppose cooking oil and old engine oil will be the lubricants, not too sure of the lubricating properties of cooking oil.

The burner cannot be drip-fed as it needs to be turned on/off quickly. The burner is mainly a replacement for my blow torch, gas costs money and my blowtorch only gives out 0.8KW, i aiming for around 10-50KW with my oil burner. Im having a go at forging a knife and my furnace is only good for melting so i thought a super-sized blow torch would be best.

For a hint take a small electric (battery operated) toy fan. Turn it on. Now stick it into a sink full of water to use it as a propeller for a boat. On the reverse, Take a toy boat with an electric motor. Look at the size of the propeller and then look at the size of the blades on the electric fan.

You are asking for instant stalled motor. The pump displacement is way too big for that size electric motor. Sorry. Look for a proper pump/motor match.

Hunt up the burner from an old oil furnace that is being retired.

The construction kerosene space heaters are another source of pumps. Find one that some construction crew is discarding due to something being dropped on it or something. They sometimes will toss one with a bad dent with a good motor and pump.
http://www.acehardware.com/product/inde ... =109365270

Alrigh mate, have a look on http://www.backyardmetalcasting.com/forums

LOTS of info there. If you will be working with it as a blow torch how about a foot pump that pressuizes the tank?

There are a few easier ways of doing what you want to do.

@ technician1002 yeah i know thats why i said that i would put a gearbox on it, anyway i killed the pump, i blew the gaskets and the seals, so i guess im going to have to make my own pump. The piston in this one is about 15mm, when i make my pump its going to be 8mm, it doesnt need a high flow rate.

@john If i used a footpump for pumping oil it would be very hard and would give out a huge output flow which would be pointless, if it pumped air for a babington then i would need to pump like mad.

I have been on backyard metal casting before but all of the burners are drip fed which take a while to heat up and cannot be shut off instantly.
Like technician said i could do with a burner thats been chucked or dumped.

My problem is getting the oil to atomize.
With a babington you need a lot of air/steam but the oil atomizes perfectly plus you can adjust its heat.
With the average burner you need the right nozzle and heat cannot be adjusted.
With the dripfeed you need to pre-heat it with propane or a fire, but heat can easily be adjusted.

Can anyone help me with a calculator. I need a calculator that can calculate the flow of air through a certain size hole and a certain pressure, then i know what air flow i need for a babington burner.

I suppose i can pump up a tank of air with a small pump and then when the burners up to temperature i can run it on steam

i meant that you have a foot pump with air and use that witht he last idea.

Airflow through an orifice table is on this page. Google is your friend..

http://www.trident.on.ca/orifice-air-flow.htm

c11man wrote:its closest to b but oil only covers up the bottom 2inches of the case.

No, its closest to C. The case is not under output pressure.

I always though it was under pressure...

Nehh of course not. It would turn the compressor into quite a scary thing... such a volume at 500+ psi? Run and find cover.

thanks technician1002 thats just what i was looking for.

Ive decided on a babington, it will run on air at first then run on steam that it produces by itself after it gets to temperature, i dont think that a fridge compressor will have enough output flow to keep it going on a high temperature because i may have 3 nozzles going at once.One to start it and get it up to temperature and the other two to give out some real heat.
I should get better atomization with 3 small nozzles than one big one.

I will still need an oil pump to recirculate the oil but it will only be around 5psi and i should easily be able to make one.

And john a footpump would work but im trying to make it all automated, plus i totally killed my footpump.

My compressor is just like C, like psycix said it would be quite a scary thing pressurising its case to 500psi. Well i think that the case will be under some pressure but not a lot, in fact it will probably be under a vacumn.

When i complete my burner i will show some pics and a video of it working, may be a long time though, 2 weeks before i can buy myself some more brass bar from the scrapyard because im making all of the valves and nozzles myself

If you have access to a good junkyard, another source of supplies is diesel engines from scrapped cars, either VW or Mercedes. Fuel pumps, injection pumps and injectors. The advantage of these parts are they use a throttle. The can easily be duty cycle modulated. For electronic injection, electronics knowledge is required to drive the injectors. Mechanical injection is easier to convert.

@John, The refrigerator compressor case is at the pump inlet pressure. When a fridge cycles off, the pressure equalizes throughout the system. The system pressure is at the vapor pressure of the liquid refrigerant. A search for a vapor pressure chart for the refrigerant will give the system pressure. Most fridge compressors are only rated for a max working pressure on the shell of about 300 PSI.

The expected pressure can be found from this chart.
http://www.chillers.com/PT%20charts%20f ... erants.htm