hole burners (propane) - hole size, spacing, design?

This forum is dedicated to the Live Steam Hobbyist Community.

Moderators: cbrew, Harold_V

User avatar
Harlock
Posts: 3833
Joined: Tue Jan 23, 2007 1:19 am
Contact:

hole burners (propane) - hole size, spacing, design?

Post by Harlock »

I've seen several hole burners lately and the unifying trait is that they are very quiet and they do not seem to need a lot of combustion height compared to LocoParts / Marty or impingement burners. The ones I have seen also put out plenty of power. This could be advantageous in a smaller firebox.

What hole size and spacing do you like to use? Also, pure propane in the manifold or is it pre-mixed?

At :56 into this video I have a shot of the burner set in Ernie Beskowiney's Canadian Moutain-type that uses rows of bars with plenty of air coming up in between for each row of holes. Even with a long train it seems to have more fire generating capability than it will ever need, which is good. You can always turn it down. No sucking out problems either, due to plenty of air. There is also a row across the back and there is an arch plate.

https://www.youtube.com/watch?v=XiTkqMkrn7o



I have asked Ernie for the parameters of the burner but he is very busy at the moment, if he gets back to me I'll relay the information here.

If anyone else would like to chime in with their experience I'd like to hear it. I have not found a previous significant thread about hole burners using Chaski search. Might be good to collect some info here.
Live Steam Photography and more - gallery.mikemassee.com
Product Development and E-Commerce, Allen Models of Nevada
User avatar
10KPete
Posts: 440
Joined: Wed Sep 30, 2015 5:29 pm
Location: Nordland, WA, USA

Re: hole burners (propane) - hole size, spacing, design?

Post by 10KPete »

Mike, I can't give you specific information but I can share what I know based upon having made some bar type burners years ago. So long ago that I'd have to start with the basic guidelines I'm going to talk about and re-do the development!!

Almost any number of holes are possible. Their spacing wants to be such that each flame just impinges on its neighbor in the same pipe or adjacent pipes. The size and number of holes in a given pipe, or pipes, supplied by one jet need to be such that there is enough pressure in the pipe to keep the flame on the outside of the pipe. The jet, and air mixer, need to be able to supply enough to maintain that pressure. That pressure is certainly small but necessary. The propane supply must be able to more than keep up with the jet so there's no back-flash possible. The jet velocity must be maintained.

When I did this decades ago I started with a 20 gal. propane tank, a .032 jet (a MIG gun tip) a piece of 3/4" sch. 40 pipe and cobbled up the usual jet mount/air mixer tube thing with a sliding tube air adjuster.

I capped off the far end of the pipe and started drilling 1/16" hole in the pipe, and trying the burn, until the flames failed to show and energetic burn. They didn't want to 'jet' out of the 1/16" holes. Then I plugged a few to get back to good flames.

If I recall, I had a four foot piece of pipe with two rows of holes about three feet long. Six feet of burner holes. Since I only needed to heat a four foot tank (a barrel bluing tank) that did the job. I was lucky!!!

Are you thinking of this for your Wendy? I've also been concerned with using those tall 'Martys' burners in that short firebox. I may have to do some more burner development work!! How soon are you wanting to build this?

Pete
Just tryin'
User avatar
NP317
Posts: 4557
Joined: Tue Jun 24, 2014 2:57 pm
Location: Northern Oregon, USA

Re: hole burners (propane) - hole size, spacing, design?

Post by NP317 »

Here are some photos of the propane burner for my 90-ton 2-8-2, 1/8th scale.
The burner nicely replicates the low flame bed of a coal fire. Btu output calculates to over 100,000!
It was designed and built by Al VonRuden, a long time member of Kitsap Live Steamers. He has built many propane burners for locos here in the NW USA.
Al was 90 years old when he made the burner shown. During testing it quickly heated up his 2-car garage in winter.
~RN
Burner 1 small.jpg
Burner 4 small.jpg
Burner 6 small.jpg
User avatar
cbrew
Posts: 3161
Joined: Sat Jan 04, 2003 12:17 pm
Location: Vancouver Wa

Re: hole burners (propane) - hole size, spacing, design?

Post by cbrew »

NP317 wrote:Here are some photos of the propane burner for my 90-ton 2-8-2, 1/8th scale.
The burner nicely replicates the low flame bed of a coal fire. Btu output calculates to over 100,000!
It was designed and built by Al VonRuden, a long time member of Kitsap Live Steamers. He has built many propane burners for locos here in the NW USA.
Al was 90 years old when he made the burner shown. During testing it quickly heated up his 2-car garage in winter.
~RN
Burner 1 small.jpg
Burner 4 small.jpg
Burner 6 small.jpg
Morning RN,
I would love to see that burner in person, just by looking at it, I have it in my mind how to build one. but i am needing details still.
I would like to build one of these for the big loco that is in the works and may even replace the burner in the ten wheeler

ttyl bud
If it is not live steam. its not worth it.
User avatar
Harlock
Posts: 3833
Joined: Tue Jan 23, 2007 1:19 am
Contact:

Re: hole burners (propane) - hole size, spacing, design?

Post by Harlock »

Well, that certainly answers the question about pre-mixing. It's a thing. And the tapered feed pipe...interesting. if you care to share dimensions some time, I'm sure Chris and I would both appreciate it. Very beautiful fabrication and welding. Looks similar to Ernie's.

The fuel / air mixer and the ID and spacing of the holes are the critical items. I did touch base with Ernie last night and he said he can get back to me once the winter weather kicks in, he is very busy laying track at home until the rain and snow kick in, weather is still good up there right now.
Live Steam Photography and more - gallery.mikemassee.com
Product Development and E-Commerce, Allen Models of Nevada
User avatar
10KPete
Posts: 440
Joined: Wed Sep 30, 2015 5:29 pm
Location: Nordland, WA, USA

Re: hole burners (propane) - hole size, spacing, design?

Post by 10KPete »

Harlock wrote: if you care to share dimensions some time, I'm sure Chris and I would both appreciate it.

Me too! In fact, if I knew the diameter of the burner holes, the gas jet diameter, and had a better pic of the gas/air mixer end of the set-up it would really help.

What input pressure do you run to that burner?

Thanks,
Pete
Just tryin'
User avatar
kenrinc
Posts: 708
Joined: Tue Jul 27, 2010 1:11 pm
Location: SF Bay Area

Re: hole burners (propane) - hole size, spacing, design?

Post by kenrinc »

Mike,

Charlie Pipes posted a similar burner a while back that used MIG tips for mixing at the back of each burner tube. I'm attaching a pic and a link from the original posting. It's my understanding that in this particular pic, the burner holes have not been drilled yet.

http://www.chaski.org/homemachinist/vie ... ne#p219909

Ken
DSC_0288.jpg
Glenn Brooks
Posts: 2930
Joined: Mon Nov 10, 2014 1:39 pm
Location: Woodinville, Washington

Re: hole burners (propane) - hole size, spacing, design?

Post by Glenn Brooks »

Al shows up regularity at our old timers breakfast on Wednesdays in Seattle. I'll ask him what diameter holes and spaceing he recommends in his burners. (Probably ihe will say it depends on the dimensions of the firebox.)

One thing he did say recently, is he initially reamed the inside of the burner tubes to clean up the little jagged edges of metal left over from drilling the holes. Latter burners he left the jagged edges around each hole inside the burner tubes intact. This created more turbulence, improved the fuel air mixture and produced better combustion.
Moderator - Grand Scale Forum

Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

Ahaha, Retirement: the good life - drifting endlessly on a Sea of projects....
Glenn Brooks
Posts: 2930
Joined: Mon Nov 10, 2014 1:39 pm
Location: Woodinville, Washington

Re: hole burners (propane) - hole size, spacing, design?

Post by Glenn Brooks »

Ok, talked to Al and a couple of other burner guru's at breakfast this morning. Here's what I,learned about design. Al's tube burners are all made with thin walled conduit to save money. They work fine, but some people like to use heavier gauge material. Leave the rough edges caused by drilling each oriface in place, inside the tubes. The roughness improves the fuel air mixture and produces a better flame surface across the fire box.

Hole size and spacing depends on the size of your proposed burner, and fire box size. Each orfice size produces a specific BTU. So total burner BTU depends on the number of holes and hole diameter. Hole spacing spreads the flame surface evenly throughout the fire box. One fellow made up a spreadsheet that contains all the necessary formulas to calculate hole size and spacing - given specific boiler measurements. If you would like to send me a PM I can put you in touch with him to work up specific orifize size and spacing that optimizes your burner.

As a rule of thumb apparently many 1/8" scale boilers have orrifice hole sizes around a #50 drill bit... so a 2.5" scale boiler would be considerably larger.

also important is the size of the Venturi that mixes the propane with initial air flow. Again, the Venturi ID depends on the boiler dimensions... this may or may not be critical for boiler efficiency - depends on who you talk to...

Gas pressure in all the boilers is around 5 PSI.. no one uses greater than 8 PSI. Most people use a standard backyard BBQ propane regulator, and quite a few use an additional simple needle value and pressure gauge in line to fine adjust fuel flow from virtually nothing (1-2 PSI) to max allowed by the regulator. Most do trial and error testing to optimize gas flow to achieve boiler efficiency.

I hope these comments are useful for planning your new burner.

Regards
Glenn P.
Last edited by Glenn Brooks on Wed Oct 05, 2016 11:56 pm, edited 1 time in total.
Moderator - Grand Scale Forum

Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

Ahaha, Retirement: the good life - drifting endlessly on a Sea of projects....
User avatar
kenrinc
Posts: 708
Joined: Tue Jul 27, 2010 1:11 pm
Location: SF Bay Area

Re: hole burners (propane) - hole size, spacing, design?

Post by kenrinc »

Glenn Brooks wrote:Gas pressure in all the boilers is around 5 PSI.. no one uses greater than 8 PSI. Most people use a standard backyard BBQ propane regulator, and quite a few use an additional simple needle value and pressure gauge in line to fine adjust fuel flow from virtually nothing (1-2 PSI) to max allowed by the regulator. Most do trail and error testing to optimize gas flow to achieve boiler efficiency.
Thanks Glenn. The comment about the backyard BBQ regulator is perplexing since they are normally preset for 10.5WC (less than 1psi). That doesn't really jive with the "5psi to 8psi" stated in the first sentence.

I'm anxious to try my hand at one of these. I've got a smaller engine with 6" boiler (3.25 x 6.25 firebox) so I think it's a good project to experiment on. Are they using electrical conduit?

Ken-
User avatar
Harlock
Posts: 3833
Joined: Tue Jan 23, 2007 1:19 am
Contact:

Re: hole burners (propane) - hole size, spacing, design?

Post by Harlock »

kenrinc wrote:
Glenn Brooks wrote:Gas pressure in all the boilers is around 5 PSI.. no one uses greater than 8 PSI. Most people use a standard backyard BBQ propane regulator, and quite a few use an additional simple needle value and pressure gauge in line to fine adjust fuel flow from virtually nothing (1-2 PSI) to max allowed by the regulator. Most do trail and error testing to optimize gas flow to achieve boiler efficiency.
Thanks Glenn. The comment about the backyard BBQ regulator is perplexing since they are normally preset for 10.5WC (less than 1psi). That doesn't really jive with the "5psi to 8psi" stated in the first sentence.

Ken-
For Locoparts burners, I would typically set the upstream regulator at the tank to 7 PSI, and then I have a Kel-F soft tipped needle valve (so when it's off it's OFF) as the firing valve, and would regulate a couple of PSI with a quarter to half a turn.

I think Glenn is really referring to the upstream regulator. With impingement burners I used even less, 1.5 PSI max. I used a 0-5 PSI gauge downstream of the fine regulator to see what it was doing. I gave up on the impingement burners due to the noise factor, very dirty flame. the locoparts burners worked great in my Chloe, but very expensive for larger engines and can't cram that many BTU's per sq in of firebox. I was impressed by recent hole burner experiences so that's why I'm heading down this path now as an experiment.

-M
Live Steam Photography and more - gallery.mikemassee.com
Product Development and E-Commerce, Allen Models of Nevada
Glenn Brooks
Posts: 2930
Joined: Mon Nov 10, 2014 1:39 pm
Location: Woodinville, Washington

Re: hole burners (propane) - hole size, spacing, design?

Post by Glenn Brooks »

Ken, yes electrical conduit. I'll have to ask more about the regulator. I havent run propane, only coal. So was just relaying info from the old time gurus. Haha, my direct propane engineering expertise generally consists of running the empty tanks down to the hardware store for refill during summer BBQ season!
Moderator - Grand Scale Forum

Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

Ahaha, Retirement: the good life - drifting endlessly on a Sea of projects....
Post Reply