It is currently Fri Jul 28, 2017 4:45 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 9 posts ] 
Author Message
 Post subject: Smokebox Interior Protection
PostPosted: Thu Jan 05, 2017 8:53 pm 

Joined: Fri Aug 27, 2004 7:57 am
Posts: 2353
Location: Faulkland, Delaware
Hello Friends,

I'm interested in hearing what, if anything, you are doing to prevent deterioration of the interior of you coal-burning steam locomotive's smoke box. I can't imagine coatings service more harsh than the interior of a smokebox of a working steam locomotive.

Thanks,

_________________
Tom Gears
Wilmington, DE

If you can't fix it with a hammer, you've got an electrical problem.


Offline
 Profile  
 
 Post subject: Re: Smokebox Interior Protection
PostPosted: Fri Jan 06, 2017 1:55 pm 

Joined: Tue Sep 14, 2004 7:52 am
Posts: 1218
Location: Strasburg, PA
I know of no way to protect the smokebox in operation, and by rights it is under the least attack while in operation anyway. Allowing the smokebox interior to be wet while in storage is the kiss of death for corrosion. Cleaning out piles of soot and capping the stack if left outside will make all the difference.

_________________
"It was not easy to convince Allnutt. All his shop training had given him a profound prejudice against inexact work, experimental work, hit-or-miss work."
C. S. Forester

Strasburg Rail Road Mechanical Department


Offline
 Profile  
 
 Post subject: Re: Smokebox Interior Protection
PostPosted: Fri Jan 06, 2017 4:06 pm 

Joined: Mon Aug 23, 2004 9:37 pm
Posts: 242
Location: Niles Canyon Railway, near Sunol, CA
Smokeboxes get hot inside and out. Regular paint cooks off.

On SP 2472 (an oil burner), the smokebox exterior was painted with high-temp aluminum paint directly onto "bare" (well, at least thoroughly wirebrushed) steel. We used Hy-Tech INSL-X Hi-Temp #AL-2402 http://www.hytechsales.com/prod2402.html. It is expensive. The smokebox exterior was painted was 11 years ago, and the paint has has held up in both service and continuous outdoor storage. The biggest problem we had is that Hy-Tech shipped the 1-gallon cans in flimsy cardboard boxes with only thin styrofoam padding at the ends. Result: Every shipment arrived with at least one can - sometimes every can - dented and leaking. (I don't know if Hy-Tech has since improved their shipment packaging...)

The silver paint on the smokebox sides was overcoated with traditional graphite paint. SP applied graphite paint to directly to hot surfaces such as smokebox exteriors and firebox exteriors. This looks nice so long as the engine stays hot most of the time. But graphite paint alone does not provide much rust protection when the boiler is cold. Hence the use of high-temp aluminum paint underneath.

I suspect that the best smokebox interior protection, in addition to keeping it clean and dry, is to sandblast to bare steel ("white metal"), then apply high-temp paint. Possibly high-temp paint with ceramic beads would survive the abrasive effects of coal cinders best of all.

- Doug Debs


Offline
 Profile  
 
 Post subject: Re: Smokebox Interior Protection
PostPosted: Fri Jan 06, 2017 6:20 pm 

Joined: Thu Aug 18, 2011 12:15 am
Posts: 38
Location: Detroit, MI
We made up some stainless steel baffle panels as an experiment for one of our locomotives when the front end had to be torn out to do some dry pipe work last year. The steel panels that had been installed less than 10 years prior had badly deteriorated and were basically just usable for getting dimensions when they were removed. So far they've been holding up pretty well. Everything is stainless except for the screens, which are regular steel mounted in stainless frames so they can be removed and replaced when worn out. Brass hardware was used because the steel hardware had eroded so badly that most of it had to be cut out because wrenches were just slipping. With the brass hardware, theoretically you can just have at it with a chisel and a hammer to break the bolts with a little less hassle. As I said, this was pretty much an experiment and only applies to the panels inside, but it's made it through one operating season without a problem, only time will tell.

_________________
Jake


Offline
 Profile  
 
 Post subject: Re: Smokebox Interior Protection
PostPosted: Fri Jan 06, 2017 7:36 pm 

Joined: Wed Feb 02, 2011 9:40 pm
Posts: 690
Whether coal or oil fired, the best that can be done is to shovel and ShopVac the accumulated sand/cinders out of the smokebox whenever you have the door open. That stuff lies there wet and simply eats the metal.

Painting or coating is a waste of time and money, IMO.


Offline
 Profile  
 
 Post subject: Re: Smokebox Interior Protection
PostPosted: Tue Jan 10, 2017 12:41 am 

Joined: Wed Oct 31, 2007 10:40 am
Posts: 69
Location: Chama, NM
Jake's comment about using stainless steel in the front end got me to thinking about that as an option. I am not thinking of building the entire smoke box out of stainless, but perhaps, the floor plate, baffles, and cyclone or screens. Other than the expense, is there some mechanical properties about stainless steel that would make it unsuitable in the long term? For example, would it be more susceptible to erosion form the scouring of cinders or react poorly to the corrosive compounds in the cinders?

I would be interested to hear how this works out after a few operating seasons.


Offline
 Profile  
 
 Post subject: Re: Smokebox Interior Protection
PostPosted: Wed Jan 11, 2017 9:13 am 

Joined: Thu Sep 22, 2011 4:29 pm
Posts: 979
Location: Youngstown, OH
Looking at some PRR locomotive test plant data on a K2sa running at 205 psi, smoke box temps were in the 500 to 600 degree range with a couple top end temps in the low 700s. Those temps are perfectly suitable for 304 and 316 stainless and is well below the point at which scaling begins, and also below the point at which intergranular corrosion becomes a factor.

What effect combusion gases have I do not know, but I would surmise 304 would fare better than mild carbon steel.

I have some bits and pieces of stainless screening and angle laying around, probably enough to build 58's screens out of. I may just experiment with it as Jake has done.

_________________
Rick Rowlands
Steel Industry Preservationist, Narrow Gauge Railroader and ALCOhaulic


Offline
 Profile  
 
 Post subject: Re: Smokebox Interior Protection
PostPosted: Wed Jan 11, 2017 2:40 pm 

Joined: Wed Oct 22, 2008 8:18 pm
Posts: 1996
The only other thing I can think of is a remetal treatment or make some kind of designed replaceable barrier of metal like driver tires have, just tossing ideas out for haggling on... 8-D


Offline
 Profile  
 
 Post subject: Re: Smokebox Interior Protection
PostPosted: Wed Jan 11, 2017 4:26 pm 

Joined: Sun Aug 22, 2004 8:31 am
Posts: 1095
Location: South Carolina
If 300 series stainless steel turns out to be suitable material, thin sheets could be used to "line" the interior of the smoke box by spot-welding to the interior.

_________________
Hugh Odom
The Ultimate Steam Page
http://www.trainweb.org/tusp


Offline
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 9 posts ] 

All times are UTC - 5 hours [ DST ]


 Who is online

Users browsing this forum: Bing [Bot], Google [Bot], Majestic-12 [Bot], Yahoo [Bot] and 17 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to: