steel nozzle liner, vedolux 37

[Coal Reaper]

doing my sunday cleaning yesterday I decided that I was not happy with the nozzle erosion after 5-6 cords. its not bad, but i can see where it is going. made a steel liner and a plate to support it. 1/4" thick all around. nozzle liner is 3/4" smaller diameter than hole in ceramics. its 4140 as I did not have any stainless on hand. will have to see how long it lasts but I am interested now to see if it burns any different. fired with silver maple tonight. initial observations are 10*F increase in boiler temp and 20*C increase in flu temp. any idea why this could be? flame looks wicked, like BL wicked. also, there is a shot of my tunnel; barely starting to get thin at the bottom.

 

[mr.fixit]

Probably just the angle of the pictures,but are your secondary air holes covered by the steel tube?

 

[Coal Reaper]

Probably just the angle of the pictures,but are your secondary air holes covered by the steel tube?

Yes and no. There is 1/4" gap between the ceramic nozzle and the od of the liner. This will let the secondary air surround the liner and still meet the wood gas as it enters the tunnel area. Well, thats the thought anyway...

 

[Chris Hoskin]

nice work, thanks for posting the pictures. It could be that the secondary air is getting very hot as it comes in around your new liner and that is causing the improved secondary burn? Please post pictures after you have burned this set up for a while, I am curious how the steel will hold up. Cool project!

 

[Coal Reaper]

While there is no wear after just one burn, there is very obvious discoloration adjacent to the secondary air ports and you can see which side of the liner is to the front and back of boiler. No pics, forgot camera. Will get some sunday.

 

[maple1]

He he, you posted this the day after I tried my first go at some kind of cheap nozzle liner.

The $5 Walmart SS steamer strainer basket didn't work out so well.

No surprise...

 

[mustash29]

Awesome looking mod, however, I would think that the intense heat in that area will quickly bake the carbon right out of the steel and leave you with a fragile & crumbling piece.

I'm new to the gassers (haven't installed or fired my Empyre 100 yet) but there seems to be many folks discussing refractory & nozzel wear. Is the wear due simply to the operation of the boiler, due to the poking & scraping of ash, or a combination of both?

 

[Fred61]

Due to the operation of the boiler. It appears the science of achieving a hot gas flame from wood has advanced faster than the ability to make materials that will withstand the environment they are exposed to.

 

[heaterman]

Due to the operation of the boiler. It appears the science of achieving a hot gas flame from wood has advanced faster than the ability to make materials that will withstand the environment they are exposed to.

True.

 

[BoilerMan]

Due to the operation of the boiler. It appears the science of achieving a hot gas flame from wood has advanced faster than the ability to make materials that will withstand the environment they are exposed to.

Well.............as I used to say when I turned wrenches for a living..........

"They certainly can make it a lot better than this, but then they wouldn't be able to sell us parts"

There are consumables in many processes, but I'd think there must be some super (and pricy) material which would give us more time before being consumed. Don't know much metallurgy, but there must be some alloy which can take the heat in the abrasive environment for a good amount of time.

This said, refractory can be made at home and is not that expansive.

TS

 

[Coal Reaper]

Still appears to be entirely intact. I will pull it out and look more closely on sunday. I think the really high temps arent seen until the secondary air meets the wood gas. Between delaying this until after the liner and the secondary air keeping the nozzle cooler this liner may last loger than anticipated.

 

[Tennman]

I was surprised when I looked up melting points that stainless is actually slightly lower than carbon steel (Engineering Toolbox). I've been shocked this season by the best ever seasoned wood and a brand new nozzle with a mild steel nozzle protector. The 3/16" plate is cut ~1/8" undersized to protect the ceramic nozzle's crisp corner. I first noticed nozzle erosion 2 seasons ago and got used to emptying ash every other day... Lots of wasted energy in those clinkers falling thru the nozzle. After a week of burning I'm stunned at the fineness and tiny volume of the ash I've heard about for years. I only removed ash this morning to do a hot swap of a broken lower ceramic block. There are lots of tough ceramic materials that would easily meet the temperature and abrasion but none of us would like the price. I think my nozzle cost me about $75 for a cast ceramic part that weighs 20-30 lbs and about 30" long. Making a nozzle from high end aerospace ceramics that nozzle would be $1,000's. My 1018 mild steel shield cost me 10 minutes with a plasma cutter. I'll let you guys know how long my nozzle prophylactic lasts. But I absolutely KNOW making the shield was much easer than replacing the nozzle and it takes just a minute to swap.

Oh... I'm also leaving some ash in the upper chamber to keep the steel covered. I think some ash protects the edge of the plate. Happy New Year all.

 

[Fred61]

Harder, more dense and abrasion resistant ceramics may be available but they may not be appropriate for the application. Boiler refractories are porous and act as an insulator and with a looser matrix (more air) they will run cooler and not conduct heat as well as materials such as 99% alumina. More porous materials will not conduct the heat further into the core so will be less susceptible to shattering from the heat. So I believe it's a trade off. We live with the wear in order to keep worse things from happening.

 

[Coal Reaper]

carbon is cooking out big time. idk how long this will last. burns are going well though.

 

[hiker88]

carbon is cooking out big time. idk how long this will last. burns are going well though.

Honest question. What is the difference between that steel and what is in my boiler? My nozzle and refractory look just about the same as my first fire last October. I'm probably at about 8 cords now.

 

[Chris Hoskin]

hiker88, the nozzle in your Fröling is actually cast iron, not steel. Handles heat better, but also has the secondary air flowing through it all the time to keep it relatively cool (and pre-heat the secondary air). We have replacement nozzles in stock, but so far (to my knowledge) have never replaced any.

 

[hiker88]

Ah I see. I take it cast iron is not something the average person can work with\fabricate.

 

[skfire]

Ah I see. I take it cast iron is not something the average person can work with\fabricate.

Making a mold not so much(if you have a foundry/eqpt), but forge welding cast iron.....

"Since the compositions of most cast irons are around the eutectic point of the iron–carbon system, the melting temperatures closely correlate, usually ranging from 1,150 to 1,200 °C (2,100 to 2,190 °F), which is about 300 °C (572 °F) lower than the melting point of pure iron"

from: http://en.wikipedia.org/wiki/Cast_iron

but also has the secondary air flowing through it all the time to keep it relatively cool (and pre-heat the secondary air)

Reason why it is very important to weekly clean the secondary pockets under the grate.
Warping the cast iron grates(among other combustion issues) will occur if secondary airflow is blocked with accumulated ash.

SK

 

[Coal Reaper]

can anybody show some pictures of the froling nozzle?

 

[Coal Reaper]

304 version will go in sunday

 

[hiker88]

can anybody show some pictures of the froling nozzle?

I'll put some up tonight around 1700 if no one beats me to it.

 

[maple1]

Is your nozzle round or oblong shaped?

(That's for Coal Reaper...)

 

[henfruit]

That is to nice looking to put in the boiler>

 

[hiker88]

I'm digging the min14 parts break down myself.

 

[Coal Reaper]

Is your nozzle round or oblong shaped?

(That's for Coal Reaper...)

round. is yours not?