Peter Brow
Burner Jets, Blazick & Screened
March 05, 2004 06:55AM
Is it really true that Blazick style jets for vaporizing burners never clog? Do they break up & blow out the jet carbon, or just catch it like a filter, eventually needing cleaning like a screen does? Too bad they don't do anything about carbon in the vaporizer...

Also, are Blazick holes usually drilled with several holes intersecting radially at one point in the jet bore, or holes intersecting bore at different points along the bore?

I have designed both screened and Blazick jets for my burner, and am wondering which design to go with.

Interesting thing occurred to me about carbon screens in vaporizing burners. A screen with undersized holes is almost as bad as one with oversized holes. If the screen holes are too big, then the jet will clog; but if screen holes are too small, then the screen will catch carbon particles which would have gone right through the jet, meaning unnecessarily frequent cleaning. Apparently jet size and screen mesh should be matched, screen holes just a bit smaller than jet.

Peter
SSsssteamer
Re: Burner Jets, Blazick & Screened
March 05, 2004 01:36PM
Blazick jets rarely clog for me as compared to the straight through standard jet. Screened jets require frequent cleaning of the screens. Blazick jets have four intersecting holes that break up the carbon deposits and allow the now smaller particles to pass through. I drill my holes at two different close points on the bore and I drill all of the way through giving me 4 holes in the jet bore. My Blazick jets very rarely need cleaning. Maybe once a year? On how often that you will have to clean your Blazick jet mostly depends on the amount of carbon that comes out of your vaporizer. And the amount of carbon you get is determined by the length of your vaporizer and what type of fuel that you are buring.
Re: Burner Jets, Blazick & Screened
March 05, 2004 02:04PM
Hi Peter

I wonder if one might be able to use a trap to catch carbon particals. It might be considered a hazard though. I am thinking of something like a ceterfugal trap. Of course the trap it's self would have be maintained at or above the vapor temperture of the vaporized fuel.

Or how about a filter between the vaporizer and burner nozle. With some valving you might be able to do a backflush through this filter and wash the carbon out.

What about an electrical vaporizer. Have no idea of how much power it would take. But the temperature could be controled and it would need nothing special for the initial start up vaporizing.

Andy
Jim Crank
Re: Burner Jets, Blazick & Screened
March 06, 2004 09:55AM
Gentlemen,
I am wondering why you are dancing all around the basic issue and not seeing it?
This carbon formation is a serious and built in problem with pre-mix vaporizer burners, not with a post-mix vaporizor.
According to a wonderful data dump that I got from the Mobile area manager many years ago, if you don't overheat the fuel when vaporizing it, carbon does not become a major issue at all. 400°F was what he recommended as the upper limit. Also, the heavier the fuel the easier it is to break it down into the major components. A lighter fuel like gasoline is better than a kerosene-diesel mix. My White would run for a full year before ever having to even think about cleaning the vaporizer, and that was with weekly use. My Stanley vaporizer was progressively reduced to six feet and it was not right over the fire, never cleaned in two years of use.
Consider trying to control the vaporizer temperature to maintain a lower temperature than what is done now.
Dobles used a separately fired vaporizer, outside the boiler casing, for their aborted Blue Flame Burner. It was temperature controlled.
Keeping a Stanley original sort of ruins this idea of controlled temperature, unless some clever vaporizer designing was done.
Just food for thought.
Jim
Peter Brow
Re: Burner Jets, Blazick & Screened
March 07, 2004 04:29AM
Pat: Thanks for the information; I wonder if the faster clogging of screens, relative to Blazick jets, is due to too-fine screens being used, or perhaps some trapping effect in the screen chamber, which catches even the small particles that should pass thru the jet? Perhaps the Blazick jet avoids some of this by allowing more of the small particles to pass through the jet?

Andy: I have been designing all sorts of carbon traps, cyclonic and otherwise, for years. Only recently did I realize that the right-sized screen or Blazick jet would be better than a trap, as it allows small particles to pass thru the jet. However a self-cleaning "all-carbon" trap might solve this problem, and might cut jet erosion too. Electric vaporizing would certainly allow very precise fuel vapor temperature control, and that would nip the problem in the bud. It would probably take a lot of electricity, though, judging by the temperature and surface area of the vaporizer tube exposed directly to radiant heat.

Jim: I did indeed dance around the issue of regulating fuel vapor temperature, because that's exactly what I plan to do with a possibly patentable control device, which I would rather have left unmentioned, at least until successfully built and running. The screens and/or Blazick jets are a backup feature, to keep the burner running in case the controller malfunctions (especially during development work with prototypes) or if a batch of bum fuel is run through the system. 400°F it is, I appreciate the tip. I wonder if the vapor temperature should vary with vapor pressure? Tests should reveal the answer.

I wonder if a premix vaporizing burner can be made as trouble-free as a postmix, gun, or other type, via vapor temperature control? I plan to find out. My experience with premix vaporizing burners has been with a number of small, mostly experimental units, nothing car-sized yet (barring go-karts). Some carboned up in jig time, others (esp commercial units) ran practically forever with zero problems -- providing years of head-scratching. In the car burner, I plan to put a temperature sensor right on the (insulated) jet, to monitor the final fuel temperature during design and controller testing/calibrating.

Currently up to my elbows in calculations, drawings, and parts/materials/tooling for this thing. Holy guacamole.

For some years now, Coleman has made premix-vaporizing lanterns and stoves which, by some reports at least, run trouble-free on ordinary modern automotive gasoline, an encouraging sign. There have been some complaints about the durability/construction of some of these (cheaply made?) units -- but not about carbon or goo problems, from what I have heard so far.

Peter
David K. Nergaard
Re: Burner Jets, Blazick & Screened
March 07, 2004 06:22AM
The fuel used has a major impact. I used a Stanley drilled burner for nearly thirty years, cleaning the vaporizor every two or three years. Then, starting about five years ago, the kerosene I could get would clog the jets very quickly, sometimes in less than an hour. No change in the burner, I am still using it, but now I burn straight Diesel and sometimes go a thousand miles without a chip in a jet.
I do use a screen in the stem where the branch fork is mounted, a la Cruban. After every long trip, I remove the cleanout screw and blow it out with the "steam enema". Last fall, when I put the car away for the winter, I pulled the cable. Nothing on after 2500 miles last year.
SSsssteamer
Re: Burner Jets, Blazick & Screened
March 07, 2004 11:27AM
Dear Peter, The Blazick jet is "self cleaning". The Blazick jets break down the carbon particles due to the turbulance made by the five holes equally trying to exit the jet. If one of the five inlet holes gets plugged, then the other four holes more less sand blasts the plugging particle until the particle can pass through the jet too. Most all of the branch forks used today have a carbon trap at the dead end of the vaporizer. The trap is the same cap that retains the branch forks and is removerd to access the vaporizer cable. On the Baker burners built by Alan Kelso and Carl Amsley, the branch forks are not removable but a pipe cap is still employed on the outside end of the main fuel vaporizer. Occasionally I remove this cap and the accumulated trapped carbon deposits inside give you an instant report on the fuel that you are using. The screen that you refer to should have holes just smaller than the jet size used. If the screen didn't, then the passing carbon would be big enough to plug your jets. Vern Wellburn, who owns a 1911 Stanley model 62, has been using screens located in his vaporizer/branch fork hole for years. He carries spare screens and usually doesn't have any plugging problems except for the continuous maintenance of his screens. I have a steam enema that I use about once every 500 miles. It cleans out the vaporizing system perfectly. The noncondensing Stanleys that run straight kerosene or diesel occassionally have a build up of unburnt fuel in their exhaust flue. When ever this gets to burning, it can be a real stinker to put out. The enema is handy to use in your noncondensing Stanley for these flue fires. A quick twist of the lknob and the fire is out. After using the steam enema for anything, it is most important to make sure the enema is completely turned off. It you don't get it turned off completely, the water that is leaked into the main fuel vapoizer makes makes instant carbon when the watere mixes with the main fuel and the heat. The Stanley type burner is nortorious for holding liquid fuel in it's outside burner pan. On firing up, the unvaporized fuel collects in the burner pan rather than going up through the burner grate. Occassionally I have seen this unburnt fuel finally reach vaporizing temperature and bleed out around the outside of the burner pan in a ball of fire. It is near impossible to put out unless you have a garden hose. Four years ago at Mt. Shasta, we used up 4 fire extinguishers on Vern's Stanley before Nick Howell finally located a garden hose to put out the fire. It was caused by accumulated liquid fuel in the Stanley type outside burner pan. The Baker Burner doesn't have this problem because any accumulated fuel will run out the front by gravity. The fix on this one for the Stanley type burner is to make sure that your main fuel is fully vaporized before fully turning on the main fuel supply knob. If the Stanley burner is properly assembled with the inner burner pan crimped around the burner grate, then there shouldn't be any liquid fuel leaking into the outside burner pan. My main fuel vaporizer is also 6 feet in length and I burn anywhere from straight kerosene to a 50/50 blend with gasoline. My vaporizer cable is ususally clean when I pull it out for inspection. Sincerely, Pat Farrell
Peter Brow
Re: Burner Jets, Blazick & Screened
March 08, 2004 07:19AM
Hi David,

Thanks, sounds like you are getting very good results. Diesel, wow, I thought vaporizing burners couldn't handle straight diesel! I will have to give it a try, maybe brew up my own dirt-cheap biodiesel in the backyard? Filler screen required to avoid blowing french fries out the jets. I have a lead on supposedly really clean 1K(?) from a fuel depot near the airport, but plan to mainly run straight gasoline. If I can get this burner running well, will definitely try various fuels and mixes and see how they work.

Hi Pat,

More great info! Blazick jets it is. Can't see how to adapt those to the filed-wire jet in the pilot light, though, so currently planning to add a screen in pilot if it is worthwhile. On the Blazick jets, I think the inlet holes are a size or two smaller than the jet? My vaporizer length is going to take some cut and try, partly because the vaporizer layout is a bit different from usual, due to the vapor-temperature control method. Currently looking at ~1/4" OD x 3/16" ID steel brake line for the vaporizer.

Interesting notes on the steam enema. Have seen pix of these on the internet, and will look into one when steam is available, though hopefully it (enema) won't be needed. Sounds great for Stanleys though. Warmup fuel accumulation, another thing to think about. I think I can avoid that with the vaporizer controller, and if it happens in development it should stay under the grate rather than get into the outer case or drool out the mixing tube. Everything will be very well sealed, with a little help from some hi-temp fuelproof sealant I located.

Sounds like well-tuned and properly operated premix vaporizing burners don't have too much trouble. Pretty amazing reliability, compared to gas cars of the time.

Garden hoses are the best for (in-car) automotive fuel fires. A few years ago I put out somebody's VW (Old) Bug that coasted to a stop in front of one of the properties with an engine fire. Garden hose pouring into the cooling air intakes under rear window put it out fast, not much left for the fire department to do. No way was I going to open the engine hood with a mess of boiling gasoline underneath, waiting for some air to explode with. Turn some of that fire into a steam blanket in an enclosed space, and out it goes.

I wonder if it would be worthwhile plumbing a steam car filling siphon to turn the elephant-drink hose into a tank-fed fire hose at the turn of a valve? Just in case.

Peter
SSsssteamer
Re: Burner Jets, Blazick & Screened
March 08, 2004 08:48AM
On the Blazick jets, I use the same sized drill bit for all of it's holes.
Mike Clark
Re: Burner Jets, Blazick & Screened
March 08, 2004 03:17PM
Burner pan fires - never had one but seen them - could you starve it of air by stuffing a wad of rag in the venturis or how about fitting a length of hose on the blowdown and filling it with steam? I realise you couldn't do this if the fire started before steam pressure was up which seems to be the most critical time. Next problem is how to get rid of the pool of fuel from the pan without starting another fire!

Mike
Ben in Maine
Re: Burner Jets, Fire on start
March 08, 2004 04:51PM
Hi,,,,,An ounce of prevention,,,,,Hmmmm,,,,,Now theres a great vision,,,,A frying pan w/ a qt of k-1 an 2oz of water on the bottom,,,,,the boiling points are not compatable at all I think I will chose the initial fire,,,,the motto is to heat the heck out of it,,,,dont be afraid of the heat ,,,it runs on heat,,,,a dry fire is safer,,,,,a wet drippy fire is worst of all,,,a dry fire goes out when ya turn the valve,,,,Have fun,,,Ben
Ben in Maine
Re: Burner Jets, Blazick & Screened
March 08, 2004 05:43PM
Hello again,,,,,Perhaps I should stress opperator error here,,,I have started the black beast on a wood barn floor,,,,,,,CAREFULLY VERRY CAREFULLY An,,thanks Dave,,for talking me through the fire I had at a local meet,,,on top of the burner AND on top of the boiler and out the top flap,,,a couple of feet,,,,no dammage at all,,not even a paint burn,,,,I remained calm so the spectators felt confident I was in charge,,,Tho I wasnt sure myself , that I was,,,While these fires attract a lot of attention,,there is always a handy valve to limit the fuel...while on modern cars the fuel pressure is high,,and no separate valve,,so a broken line usually ends as a total meltdown,,,Be sure you know where all the fuel valves are,,Cheers Ben
Peter Brow
Re: Burner Jets, Blazick & Screened
March 10, 2004 01:32AM
Thanks Pat.

Ben, yep water is far from the approved choice for Class B fires, yet oddly it works quite well, at least in cars. Just watch where the water goes, of course, as it can carry flaming fuel along with it. Around dry brush, woodpiles, wood structures, feet, etc there could be big problems. A calm "stand back" is good for bystanders. "Steady on" is the thing with these kinds of fires, they can be very unnerving, esp with several dynamite sticks worth of fuel tank nearby. If the fire gets near the tank, then "discretion is the better part of valor", ie, RUN. Hope I never have to deal with another one, esp not next to a wood-frame building I own, with everybody else in the vicinity going ape-shizzle over the expected 1970s TV cop show car explosion.

Peter
Mike Clark
Re: Burner Jets, Blazick & Screened
March 10, 2004 04:31PM
Wasn't thinking of watering the fire from the blowdown - more trying to eliminate oxygen by pushing steam in. I have tried putting out a pool of burning kerosene with a hose from the blowdown - it did work but too much steam sends the fire everywhere. DON'T TRY THIS AT HOME!!!Capping the venturis would kill the draft and cut the oxygen too as long as the jets had stopped feeding fuel.
SSsssteamer
Re: Burner Jets, Blazick & Screened
March 10, 2004 06:54PM
Dear Mike, On Vern Welburn's 1911 model 62 while it was burning at Mt. Shasta, we did plug the venturis. It didn't make any difference at all. The pool of fuel in the burner pan had reached the temperature of vaporization and the fuel vapor was pouring out any crack that it could find. Where the worst damage occured was at the rear of the burner pan the fuel vapors were escaping and they had caught the firewall on fire and burned it to a crisp. On the left side of the car, the flames were coming out there to. So bad that it burned all of the paint off of the left front fender. I think that a slight breeze from the right is why the flames went to the left. Our fire extinguishers would put out the flames and as soon as the vapors found an ignition source the flames were immediately back again. There were many hot spots to light off the vapors. Two fixes for this problem were first to open the top of the hood and then open the boiler smoke door on top. This let the heat go straight up instead of sneaking around the fire wall and burning that up. And finally, the cold water cooled the hot spots so the fire would stay out. Our extinguishers were now empty so it was a very good thing that Nick found the water hose. I blew the flare off of my fuel presure gauge once while it was at 140 pounds. The top of the hood was open when this happened and flames shot 22 feet straight into the air. I immediately closed the hood to contain the fire ball, then dashed to the main fuel hand bypass valve and dumped my main fuel pressure. With my halon extinguished, it took only three blasts of it from above into my hood before the flames were out. When I got home, I increase my insurance policy on our sooted up Stanley. I did loose the paint off of the hood. This happened on a desolate country road while I was relighting my pilot. The light pole next to our car is what we measured the height of the flames with.
Mike Clark
Re: Burner Jets, Blazick & Screened
March 11, 2004 02:17PM
ssssssssssssssssssteamer!

Frightening experience!

The Model H doesn't have an opening panel in the top of the hood and as one of our UK owners has discovered a big fire with the hood standing vertically will melt the solder holding the hood together. Fortunately my hood flaps back to rest on the steering wheel while I am firing up (no windscreen) so a big flame up would miss it. Still I think I will put an opening flap in the hood as this might help relieve pressure when I get a bang which at the moment generally lifts the smoke hood because the top flap is prevented from lifting by the hood. It would also let me squirt at a fire from the top without opening the whole thing.

Halon extinguishers are banned in Europe - how do you find the AFF foam ones which we now have to use - are they good enough? What happens with a dry powder extinguisher which wouldn't do any cooling?

Mike
SSsssteamer
Re: Burner Jets, Blazick & Screened
March 11, 2004 04:12PM
A flap on the top of your hood is a good thing to have. If my pilot ever goes out, I first wave my torch over the opened flap and smoke door first before I even attempt to light it from the peek hole. It keeps things together longer doing it that way. It lights off from above over 95% of the time. I usually don't even look into the peek hole when it lights from above. If you put a flap in your hood, put a check chain with a spring on it too. It will keep from bending things up when you get a good pop. Halon is hard to find here for refilling our Halon extinguishers. If you find it, it is expensive because we're only working with what's left in our old inventories. When Halon is gone, it is gone. I haven't yet used the foam you referred to. The dry powder extinguisher not only makes a mess, but once you have used it, the extinguisher is spent. It has lost it's seal. The dry powder also plugs up your burner plate and seals it tight like Portland cement. Keep it away from your venturis. CO2 sounds like a better alternative to use because it still can be used over and over again without it bleeding the rest of the CO2 out of its bottle between uses. The fire I had, my wife was sitting in the front seat when the fuel line blew. And she watched as the flames shot 22 feet into the air and she noted the height they reached on the light pole we were parked next to. After 39 years of marriage, she still hangs onto my shirt tail and she isn't afraid of operating a Stanley steamer. I am a lucky guy!
Rolly
Re: Burner Jets, Blazick & Screened
March 11, 2004 04:34PM
I have very rarely had my pilot go out. But I have found patience works best. I first use the steam exhaust blower then open the top trap door and do as Pat does with the torch. I have not had a woof yet.
Two years ago when I built a new burner pan I had some scrap 310 S.S. left, so I cut a strip about 1/8-inch wide and wrapped it around my pilot vaporizer. It turns red and acts as a re-lighter. I guess its working very well or my pilot has been but I have not had to get out to re-light for a long time.
Rolly
Peter Brow
Re: Burner Jets, Blazick & Screened
March 11, 2004 08:57PM
Has anybody tried a manual-reset thermostatic shutoff that senses when the pilot light goes out, and then shuts off the pilot and main fuel? Only slightly unoriginal, and might save some woofs, damage, and sky shows. I plan to try something like this in my burner.

I have also read of people putting a wee loop of nichrome glow wire by the pilot, to relight it, and probably the main burner too, if the pilot takes a nap. If it were only a fraction of an inch of hair-gauge wire, it probably wouldn't take more juice than a tiny light bulb. With noncondensing Stanleys you have the problem of adding electricity (a hidden motorcycle battery?). Rolly's ingenious approach avoids that problem, at least until the pilot & main burners have been out for a while.

Alas, these things spoil some of the fun. smiling smiley

Peter
Arnold Walker
Re: Burner Jets, Blazick & Screened
March 12, 2004 06:26AM
Halon is freon by another tradename and is baned in the US except for surplus stocks as well. Nothing is as good on an engine fire as halon
....liquid nitrogen has some interest in the short term for airline automatic fire control.But no positive alternative fire control agent to replace halon.
Nitrogen is used like a CO2 firearrestor,but no global warming suits from
the eco people.....
Mike Clark
Re: Burner Jets, Blazick & Screened
March 12, 2004 03:54PM
I have an electronic sparker off a gas fire which stays on all the time to keep the pilot going - it only fails if the pilot gets too cold to vaporise properly (using unleaded) or if, as sometimes happens, the pilot gets starved of air by the force of the main burner. Some of our chaps use propane pilots and have fitted temperature cutoffs like you suggest.

On halon - it's obviously the best extinguisher because the only places it is now legal to use it in the UK is on aircraft, by the military and in government offices ---- politico's always look after themselves first! We are not even allowed to sell or even use up old stock.

Mike
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