Came across an interesting series of letters from 1927. In the letters a purchaser of a (well) used locomotive from a used equipment dealer (General Equipment) is complaining about leaking flues (among other issues - badly flat spotted drivers, frozen linkages, clogged pipes etc.)

In response the equipment dealer stated that the flues were installed and rolled when the locomotive was coal fired and now that it had been converted to oil fire the bead was incorrect. He stated that it should have a smaller bead for oil fired and that the purchaser was using the locomotive too hard with in-adaquate maintence.

I have never heard of this. Is this correct? Or... was the dealer trying to deflect the accusation?

It should be noted that in the letters the purchaser accused the dealer of buying the engine for scrap value and passing it off as good for service. The dealer stated that wasn't the case and had barley cleared $300.00 on the deal.

All neat stuff!

According to the Railway Educational Bureau pamphlets on Boiler Flue work (Unit PA. 1, page 23) the end of the flue should extend 3/16 to 1/4 inch beyond the face of the back flue sheet. No distinction is made between coal or oil fired locomotives. The process of beading is described on page 25 and again, no distinction is made between coal or oil fired locomotives on the method of beading over the end of the flue against the flue sheet.

I have heard that oil-fired locomotives tend to be harder on flue ends than coal-fired locomotives.

Hope this is of some information to you.

Ted Krumreich

In my own mind, it appears that the vendor is trying to shift some blame, however, the flip side is; there is some reality to what he is claiming as the real problem. Here are a few things to think about that are real life situations and conditions.

In a coal burner, we have seen tubes beaded over with very heavy beads. This is due to the fact that tube ends can be "shaved" away or "cinder cut" by the passing of cinders, ash and other trash in a coal fire passing through the tubes. In fact, it was a common practice to apply "cinder shields" to stay bolts. This was commonly done by applying a weld around the stay bolt attached to the side sheet only in such a manner that the flying cinders would hit the weld and cut it (the weld) down, before the head of the stay bolt was cut down by cinder cutting.

Tubes did not have cinder shields, they were replaced too often and there is really no way to apply them. Super heater units on the other hand had cinder shields around the necks of the units to protect the piping of the units.

So....indeed, we "could" say that a coal burners "could" have a thicker bead, but to say it was a specific standard practice, ummmm.....not so much.

The process of installing tubes has had and still today has many faces. Though we could argue the proper or most correct method, we have come to find, as we have debated and discussed the issue with fellow piers and competitors that a few general rules should always apply to tube installation. These basics are as follows and are generally considered correct by the bulk of us doing these repairs often in the industry.

If you roll a tube in and you do not bead it, make sure that the edges of the tube have been rounded off. A sharp edge of a tube will create a hot point in the tube and will ultimately cause a crack in the tube that is non-reparable. Keep in mind beading is NOT a code or FRA requirement. You can do it, you are not required to do it.

If you seal weld a tube, after you install it, keep two things in mind, the seal weld is not really there to "seal" the boiler. The weld is really a heat sink, used to draw heat from the tube and prevent the tube from cracking on the end. Like the above case, make sure that all sharp edges have been removed before any fire (coal, oil or otherwise) is placed in the fire box. Again, the sharp edge will cause tube cracking. If you seal weld a tube, it is vital that you go back and re-roll the tube one more time as the welding process will release the first roll and create a gap between the sheet and the tube. This gap can trap moisture which can damage a tube in an area where the tube is thin and cause tube failure (keep in mind it is not the moisture that caused the damage, it is the oxygen in the moisture that causes the damage, the moisture is the vehicle that caused the damage).

Now, combinations of any of these practices? All acceptable. For example, Rolling beading and seal welding, rolling a second time.....fine. Rolling seal welding, no beading and rolling again....fine. Rolling, no seal welding, no beading, no re-rolling, fine.

For one that has ever beaded a tube, you will find that every tube beads a different way and there is no way to get tube ends to extend past the sheet the exact amount on all tubes.....you learn to accept the fact that close was good enough! Now, too long is no good and too short was a wasted tube.....in this boiler anyway, maybe you can use it in another boiler!

Air flow and temperature in the fire box can play a major part in tube problems. We have many here in this group that will speak to this issue much better than I and with more detail. I defer to them. If you want to see installed tubes, of all kinds, see our web page and the many boiler projects we have done. If you have additional questions, feel free to throw them at us. This was a good one indeed.

My signature includes a link to our web page. Look in the projects section for photos of installed tubes.

Thank you,

Mr. Rimmasch,

Seeing that we've stumbled on the topic of flue rolling/beading, I want to bring to your attention a specific single roll bead expander. This tool is made by the Elliott Tool Technologies and is denoted as the 4480 series single roll bead expander. Have you any experience with said tool or similar derivative? And, do you think it wise for those in the steam locomotive preservation industry to invest in such a tool versus such methods as seal welding for example?

From my own experience, I would opt for a tool such as this one in the video below. Expanding and beading the tube in one motion, while leaving a machine-smooth bead would alleviate any unneeded stress on the tube ends during installation. Therefore, there would be less flaws (i.e sharp edges) that may prompt cracking later on (at least from a theoretical standpoint). Also, it would be more efficient time-wise to re-tube the entire boiler if one were to consider this option. What are your thoughts?

DC

http://www.youtube.com/watch?v=QtKQAQQqNfA

Donald,

Thank you for the note and the question. I have indeed seen the Elliot Tool (we have a number of Elliot Rollers on hand) and we have been "picthed" the idea of buying the combined tool. We have also looked at a competitors version and I must defend the video in one minor area.....my defense is also the reason why we do not use this tool as a "restoration" tool.

In the video you see two different results with a "like" tool, the one tool by Elliot and a competitors tool. The problem with the video is, we do not know the actual size of the hole the tube was installed in. The Elliot rep told me that even if we tried to roll a larger 2 inch tube with his roller, we could end up with some "edge" issues. The reason for this is that the beading portion of this tool is fixed on the outer collar of the tool, it does not move. As such, it assumes that the tube size (finished) will remain with-in the tolerance of the tool. For example; a two inch tube hole may actually be 2.165 in physical diameter. For a new tube plate and a new tube, with a close tube-to-tube hole tolerance, this tool is great! The video shows the tool in use on what appears to be a Cleaver Brooks Class C or D power boiler.

In steam locomotive restoration we often end up with tube holes of varying sizes. Some, beyond what "normal" practice may allow. For example in the steam locomotive world we encounter King Holes. King Holes are holes in a tube plate specifically made larger to accommodate the installation and extraction of tubes. This combined machine, in our application does not cope well with the larger holes we encounter.

Notice that the mandrel of this roller is not too long and does not have much tapper in it. The historic rollers we use are much longer and have more tapper. For example, a tube expander of the two inch size, in a historic tool, in some cases, can roll up to 2 1/2 inches. The Elliot Tool, if I recall, only went to just under 2 3/16.....which means, the tube hole, must be with-in spec for the roller to get a good tight roll and to apply the bead.

Now, say you called us and said, hey Wasatch, come install 6 new tube sheets on our three locomotives (we would be doing front and rear sheets) and say, you told us to roll and bead all tubes and that you wanted tube hole sizes to be just over 2 inch (say 2.165) and say, you excluded us from using shims. Would I use the machine now.....I would be the first to buy it! New tube sheets, tight holes, no shims, beading required, single process.

Now, same three locomotives and you called and said, come and install new tubes in existing tube sheets, sheets have king holes, some holes are not even round and we may have to repair some holes or even some sections of the tube sheets. In this case, give me my historic and old rollers, a box of shims, my air hammers and let me go at it!

My final answer....good machine for the right application. However, historic boiler work, not the right application.

Thank you for allowing me to share my thoughts on the matter!

"For one that has ever beaded a tube, you will find that every tube beads a different way and there is no way to get tube ends to extend past the sheet the exact amount on all tubes.....you learn to accept the fact that close was good enough! Now, too long is no good and too short was a wasted tube.....in this boiler anyway, maybe you can use it in another boiler"!

Perhaps I misread the above comment about tubes cut to the correct length however I will add my comment on what we did so that we didn't have wasted tubes.

Tube length is important especially when you need the correct length proud for beading. I believe that in most cases a tape measure is used in each tube/flue location to determine length then that dimension is called out to the mechanic manning the chop saw. Last time we installed flues we made our measurement using what we found to be the longest flue and usually one or some will be slightly longer than others and this can mess with your beading. Using the longest measurement I added 1/2" then cut all flues and installed. In rolling we then staked one end with the proper amount of flue standing proud, 3/16 using a guage then rolled the flues tight on one end. Once this was done the other sheet was worked on but all the flues/tubes were slightly long. What we did was to use a pneumatic end prep tool which is just a lathe that clamps to the inside of the flue. This end prep tool then cuts the flue down to the proper length and it is easier to control so that you get an exact dimension. We found that this was much faster than cutting each tube to a unique length. The end prep we used is made by Esco
http://www.escotool.com/shopping/Millho ... index.html
Watch the vid, these are nice tools.

One other thing that we found that this tool could do was to shave down the beaded tube end and some of the seal weld. This saved time from having someone inside with a grinder for days and days. If you get to be very good with this tool you can actually cut down inside the flue past the thickness of the flue sheet. Once the bead is cut and the flue thinned you can wrest the stub out with a pair of channel locks. Be careful with this though as you can cut past the tube thickness and into your tube sheet. Here are youtube vids on bead removal.
http://www.youtube.com/watch?v=jiKNb8NZM7o
and seal weld removal
http://www.youtube.com/watch?v=ptuI6p9jRYc

On the king hole I found that with a good sheet and new tubes that the tubes and flues were easily installed in the respective locations however in removing old flues that because of the scale the king hole was needed.

While perhaps not in ASME code, it was the standard of most(I would say all but do not actually have reference material on ALL railroads/manufacturers) railroads and manufacturers to bead ALL tubes on the firebox end and no less than a certain percentage (20% comes to mind) or one of several acceptable patterns on the smokebox end.
This practice is required to effectively brace the tube sheet against the forces of the internal pressure. The tubes act as longitudinal stays no different than the those of the unsupported areas of the front fluesheet above the bundle and the backhead above the staybolts.
I have (somewhere) a report that speaks of boiler explosions, it goes into detail regarding the cause be it mechanical failure or human error.... One such case details that the front tubesheet failed due to a lack of any beaded tubes, another such case referred to an insufficient number of tubes having been beaded.

In the baldwin standards books it is stated that on oil burning locomotives ALL tubes are to be seal welded on the firebox end. This standard dates (IIRC) from the 30's. In doing further research on the subject I found it to have been concluded that due to the more rapid thermal cycles, and more direct contact with flame, this was greatly advantageous in insuring the longevity of the tubes.

Jason

Since this thread has come to deal with a number of tube installation questions, I'll add some of my own.

First, does anybody still prosser tubes for locomotives? I ask because when 1225 was retubed in the early '70's, the C&O boiler maker involved rolled, beaded, prossered, and seal welded the tubes (not necessarily in that order). The tubes were safe ended and also used copper ferrules. When the FRA wouldn't give the engine any more extensions (1994 or 1995) because of several tube failures (pitting in the old parts of the tubes), this boiler maker was no longer around and we had not come up with the appropriate prossers, so the engine was retubed using rolling, beading and welding with new tubes and steel ferrules. I get the impression that modern boiler practice seems to regard rolling versus expanding (prossers are a form of expander) as one or the other with rolling preferred. But recently, I was perusing the Johnston Brothers Boiler website and was surprised to find the description of their tube installation process includes prossering. I haven't persued whether these are old stock prossers or if someone still makes them.

Second, I'm aware of the bad things that happen when molten copper encounters steel. But I'm also aware of standard practices that use copper ferrules and seal welding. Do we avoid ferrules because of concerns about messed up weld metallurgy or is it because we don't have the tools to install them safely? The same standard practices specify installation with special ferrule expanders that set the ferrule back from the face of the tube sheet. Tubes were being welded with roundhouse generated acetylene and swedish iron wire before the Bureau of Locomotive Safety was formed. By WWI, the merits of gas versus carbon arc welding were being debated. In the 1920's, the new thing was bare electode arc welding. The shielded metal electrode didn't become generally available until 1929. Ferrules were used with all of these methods when welding tubes.


Andrew Adams

A Prosser is used to expand a tube inside the sheet. Normally used to help seal a leaking tube. Using a pross makes it harder to remove a tube. I was taught to use a Pross only as a last resort.
I have never heard of problems of using copper ferrules & seal welding. With the tube & sheet acting as a BIG heat sink this should not be a problem I would think.

Dave