WW&F No. 10 - Official Work Thread

[Dag Bonnedal]

I'll second that question! 

I'm also curious about wether Jason thinks the mill scale has to come off the boiler plates before everything gets put together. I'd never thought of it, but recently saw one of the Ffestiniog shop guys mention that they remove it as, IIRC, its presence causes accelerated corrosion in places with no mill scale. As for how they remove it, forget grit blasting! Apparently they just leave all the components out in the yard for a year to get nice and rusty. Of course they have security cameras around BL and the pieces aren't exactly easy to cart off... 
I'll see if I can find the post.     

I read that as well and it was also new to me, they did not recommend grit blasting (as it scorches the surface). Instead they just leave the plates and components outside in the wet Welsh weather for up to a year.

When we got our superheated 2-6-2T  No. 9 on long term loan from a museum and cut the tubes out 10 years ago, we noticed that they were almost entirely covered with mill scale. The loco got a new firebox in 1945 and was put aside a few years later! But the end of the tubes (2" in the firebox end) were severely pitted with through holes due to galvanic corrosion from the copper firebox.

Dag B

[Ed Lecuyer]

Any resemblance to any individual, real or imagined, as drawn on the backhead is coincidental. No association of any type is expressed or implied. Your mileage may vary. Action figures (or action ducks) are not included. Objects in mirror are closer than they appear.

[ALAIN DELASSUS]

Hi ! Please Could you tell me what the mud ring is. I can find any  proper translation in my dictionnaries .

[Rick Rowlands]

It is a rectangular piece of steel that is placed at the bottom of the firebox to fill the space between the outer firebox sheets and the inner firebox sheets. 

In this video you can see a rivet being installed in the mud ring.
https://www.youtube.com/watch?v=OLKR_jxQCqw

[Bill Baskerville]

Hi ! Please Could you tell me what the mud ring is. I can find any  proper translation in my dictionnaries .

Alain,

The sediments contained in the boiler water settle down to the bottom of the boiler on the mud ring where it surrounds the firebox.  This is why it is called a mud ring.  There is a dump valve located along the bottom and periodically the fireman preforms a blow down operation which opens that valve and water and the sediments are blown out thru a pipe under the cab.  Since the water surrounding the firebox is under the same steam pressure as the steam going to the driver cylinders, this is a very noisy operation, but keeps the mud ring at the bottom of the boiler clean of sediments and debris.

A similar question came up in a thread that related to the water chemistry.  We treat our water to reduce scale.  But the chemical conversion increases other chemical ratios in the boiler water.  The blow down serves to reduce the water level in the boiler so it is replaced, and diluted, with fresh water from the tender. 

So, the blow down accomplishes two things, reducing sediments and solids and balancing the chemical composition of the boiler water.

We all learn by asking.

[Wayne Laepple]

Alain --

You may know the mud ring by its British or continental name, the foundation ring.

Robert --

The mud ring is solid and is riveted to both the firebox (on the inside) and the wrapper (on the outside). They are long rivets.

Cheers -- Wayne

[Bob Holmes]

So to further the education of the uninitiated, what happens in the space between the firebox and the wrapper?  Thanks.

[Ed Lecuyer]

That space is surrounded by water. This is what (effectively) keeps the entire firebox from melting from the heat of the burning gas. Above the firebox's "crown sheet" (top) is the area occupied by steam, which then gathers (ultimately) in the steam dome (highest point of the whole boiler) and fed via the throttle and dry pipe to the cylinders. Again, if the crown sheet is not covered in water, it too will fail, and bad things will happen.

The mud ring is the lowest point of the boiler, so it is always full of water. It is also where all the sediments in the water settle, etc.

(@Jason, how'd I do? :-)

[Carl G. Soderstrom]

That water filled space on the side of the boiler is often called a "Wet Leg"
which may not be in Alain's dictionary.

[Nyle Buxton]

  3M, Scotch-Brite makes a Clean and Strip discs/Pads which work exceptionally well on removing mill scale. They can be purchased at Home Depot.  I have used the black ones, I believe they come in Purple, (Silicone Carbide) and maybe a few other versions. Check the 3M website. They can be purchased to fit on a 4.5" angle grinder among other things.   That is unless you want the boiler to sit outside for a year....rusting

Nyle

[Rick Rowlands]

Just abrasive blast the boiler before putting the Apexior on.  Never have to worry about it again. 

[ALAIN DELASSUS]

Thank you so much Rick, Bill, Wayne, Bob, Ed and Carl for answering my question about mud ring and giving all the explanations about the back part of a boiler. I've learn quite a lot of vocabulary.  The mud ring in French is le cadre du foyer the lowest part of the boiler. Since 1988 all our locomotives have been fit with a blow down valve.The inner fire box sheet is called in French le foyer and the outer fire box sheet la boite à feu the crown sheet is le ciel du foyer  which one or two fuses are screwed through to avoid crown sheet damaging or boiler blowing up for lack of water. Fuses called plomb fusibles are compulsory in France.

[Keith Taylor]

which one or two fuses are screwed through to avoid crown sheet damaging or boiler blowing up for lack of water. Fuses called plomb fusibles are compulsory in France.

Alain, actually the French name is very close to the terminology we use here. The most common name is fusible plug.

Keith Taylor

[ALAIN DELASSUS]

Thanks Keith. An other  stored up RR vocabulary word. Locomotives crews were haunting with melting them because in France it was with  the worst mistake they could make .

[Mike the Choochoo Nix]

Fuses called plomb fusibles are compulsory in France.

Since the Latin for lead is plumbum I would guess the a translation would be "lead fuse" as most are filled with a lead or tin mixture