Apologies, Dave, but Panzer, auf Deutsch, means "armored." Etymology is through the French pancier, ‘breastplate’, from Latin pantex, ‘belly, paunch’. A Panzerkampfwagen is an "armored battle vehicle".

So it does indeed translate nicely as to copper-armored-steel, that is, copper-coated or copper-plated steel.

German for panther is, well, "Panther."

Hello All:

I did a little more digging and I ran across "kupferplatierte stahl" on some documents dealing with small to medium size projectiles, essentially rounds used in small field guns of 5 cm to 10 cm bore. The documents show the various markings on the base of WWII german ammunition. In this case, the base of the shell was stamped "kps".

"kupferplatierte stahl" does translate as "copper plated steel". Copper plating of small to medium projectiles was a method used to improve armor penetrating capabilities. According to the documents, the layer of copper acts as a lubricant to allow the steel projectile (probably hardened) to better penetrate armor.

As for the references to "swedish steel" this dates back to earliest days of commercial steel making. Bessemer did his original work using Swedish iron ores. His first steels were quite good. However, as his process was expanded to utilize other ore sources in different countries, the results were not always as good. Some steels produced were quite brittle. It was later determined that this was due to the levels of phosphorus present in the ores. Swedish ores were naturally low in phosphorus. The result was that "Swedish Steels" were quite ductile in the early days of steelmaking compared to other ores.

I would like to take a look at the original german documents if anyone has them.

hth

PKurilecz

Not at all, Erik - never an apology necessary, and thanks. I was a very small child and my Pa Deutsch Great Grandfather didn't speak any too clearly........ but the imagery was comforting for a while, and the nostalgia enjoyable. He did give me my first sips of Iron City even before I was in grade school, maybe that's the problem.

And thanks, P for solving a mystery I've been unable to solve since an old boilermaker tried to sell me a bunch of old stay stock and Swedish Steel was the only material spec. Probably a good thing I didn't take it.

dave

Dave
Found the "Henschel Locomotive Design Book" on eBay about a year ago. In English vintage 1959.

Matt

STAYBOLTS
Flannery Bolt Company
by G. R. Greenslade (1940)
courtesy of Dick Stone (about 15 years ago)
Download Full Book(2MB)

Matt:

That's a really interesting piece. Tross's work (1951) explained that maximum staybolt stress occurs as the firebox plate cools from expansion.

When the firebox plates are hot, the staybolts are preventing expansion. Corrugation occurs rather easily due to the very high plate temperatures which allow it to deform easily compared to the cooler staybolts. The plate is essentially gathering up material so the staybolts are relatively straight when the boiler is under fire. When the fire is extinguished, the plate material becomes much stronger, and as the plate cools and shrinks it exerts great force on the staybolt. This is Tross's explanation for why cracks occur at the same clock positions.

Tross went further to examine these localized effects and how they do things to the boiler in general like make the sides of the firebox "hog" etc.

I think it was the discovery that boiler deformation was the cumulative effect of different local bending stresses that caused Greenslade to endorse Tross so heavily. Unfortunately, the product of this collaboration was mostly unrealized.

Matt Austin,

Thanks for the Flannery booklet. I recalled seeing some of the illustrations in a Flannery catalog and it's nice to know where they came from. Since this was from Vol. 9 No. 1, I wonder what the other booklets would have covered and indeed if they still exist? I assume this publication was either a Flannery house organ or a series of marketing pamphlets.

As an aside, the boiler used in the firebox temperature determination appears to be from a NYC L-1 Mohawk. I would speculate that it was either 2500, the first Mohawk, which was a one off that was extensively tested before more were ordered or 2569, which was rebuilt into a 3-cylinder experimental while retaining its original boiler. Either would be logical candidates for boiler capacity measurements.

I think this work by Greenslade and Tross compliment each other. Greenslade determines uncompensated expansion and Tross works on where it goes -- buckling, bulging, and plastic deformation.

Andrew Adams

On a second perusal of the Flannery booklet, pages 27-34, I noticed that the modulus of elasticity of iron was used for the staybolts while the modulus of elasticity of steel was used for the sheets. Also, on page 32, the derivation comparing rigid and flexible staybolts uses the same modulus of elasticity for both. This implies that the the flexible staybolts were wrought iron as well. This was appropriate for an L-1 boiler built in the 1916-1918 timeframe. Indeed most rigid staybolts were still wrought iron at the end of steam, but later flexible staybolts were manufactured from steel. The derivations and caluculations need to be changed to reflect the modern practice of using steel staybolts.

In particular the table on page 33 needs to be reworked. The expected result of this would be greater bending of the sheet relative to the staybolt.

This has me thinking about the replacement of old wrought iron bolts with steel bolts in repair situations. When deflected by sheet movement, which would reach its yield point first? Would a single steel bolt surrounded by iron bolts break first? I think I have some materials to research and some numbers to crunch.

I'll try to give some consideration to what the additional sheet bending will do as well, but, as I don't think the problem is as straight-forward, I don't promise firm conclusions.

Andrew Adams

Matt J

Both the Henschel Locomotive Design Book and the Tross Papers describe a permanent backend distortion or "vaulting".

Would you be so kind as to summarize this phenomenon? I have never been exposed to this.

Matt A

Matt A.

I am very impressed with the papers you have posted. May I say, Thank you!

Matt, I realize that you asked Matt J. to address your question. If you will so allow, I would like to tell you what I have seen.

In an earlier post of mine I explain that I tend to want to install Tross style bolts in areas of the boiler that are subject to higher heat and therefore more stress and potential movement. The locomotive I use for this case study is the 141R 568 in Switzerland which my companies maintains. I have examined three other 141R boilers as well.

Last year we were required by the Swiss Boiler Inspector to remove and install new stay bolts in the lower portion of the back head/door sheet. The extent to which we replaced bolts was the last two vertical rows of stay bolts on both side sheets about half way up the sheet or just over the door and the entire back head/door sheet to the same height.

As we removed the rigid threaded bolts (believed to have been American procedure Iron Bolts installed by SNCF) we found many of the bolts, primarily in the lower section of the replacement area to be “heaved” or what would appear to be permanently stressed and or bent. In most of the cases, the bolts were bent in such a way that they looked like the diagram included in the papers you posted. Some of the bolts, which were newer and installed by SNCF using SNCF practice were steel bolts with fillet welds (only a few bolts). Even these bolts were bent or heaved. What I found most interesting is that there was no defined manner in which the bend pronounced itself. In other words, I can not say that all the bolts bent downward.....or upward.....or to the left or right. Though I can not define a pattern for all bolts, I can somewhat define a pattern in relationship to the direction of bend in the bolt and the area of the fire box.

Example. In the right back corner of the fire box, closer to the side sheets, the bolts bent toward the side sheet, as if to say that the door sheet was moving toward the side sheets and taking all of the bolts with it. Under the door, the bolts were bent downward, as if to say that the bolts were bending away from the door. On the left side, same thing, the bolts were bent to the left side as if the door sheet were moving toward the left side sheet. Of most interest, the two vertical rows of bolts in the side sheets seemed to be straight, with little or no bend. I can only attribute this to the fact that the rigid corner of the foundation and the flanged sheet of the door sheet aid in keeping the side sheets rigid and less prone to movement (where can that area go?)

An inspection of the inner sheets with a scope showed that the bolts in the center portion of the two side sheets, below the brick (as noted in my other post) were bent.....not broken, but notably bent. Though these bolts were not broken, I believe, as I have seen first hand, that in these areas of the boiler, a Tross style bolt will have a longer life span. I again maintain that the form of attachment has little effect on the life span of the bolt. The design of the bolt, coupled with the stresses exerted on the bolt alone, excluding any discussion of form of attachment are the leading causes for bolt failure.

I believe that true movement of the sheets and bolts was never a direct focus of the Class I Railroads. I believe, as you (Matt A.) have shown that the “after market” shops understood this the best. However, since these shops, including the shop that wrote these papers, was an “after market shop” the Railroads discounted the findings. Had the railroads listened to or read this information, it would have come with cost implications. Steam was too far dead to heed such advise.

John E. Rimmasch
Wasatch Railroad Contractors

http://www.wrrc.us

John E. Rimmasch

I am NOT WORRIED about the life of the bolt. In a boiler design the failure of the bolt is the LEAST CATASTROFIC form of failure. The failure of the ATTACHMENT where the side sheet is COMPROMISED by the attachment type DEPPLY CONCERNS ME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
THIS IS BECASE A SIDE# SHEET FAILURE REQUIRES A DIFFERENT LEVEL OF ATTENTION THAN A BROKEN BOLT!
Robby Peartree

Robby,

Thank you very much for the response. Robby I value your opinion and truthfully Robby, I really want to sit down at dinner with you and debate (discuss) a few things. What I want to discuss person to person is:

If you are that concerned about a fillet weld, how can you not be concerned with the heat effected zone in a full pen weld? Building on the same train of thought, a fillet weld is a form of attachment that you can inspect 100% of the attachment. A full pen weld and or a threaded bolt can not, with the naked eye, be inspected 100%.

Additionally, how can a fillet weld be that bad?......remember, there are far more service hours with far fewer (recordable) failures than we have with a threaded bolt. The fillet welded form of attachment is well proven by far more countries than our own. I want to discuss the proven and document-able failures of this form of attachment with you.

Last the discussion at hand has to do with stay bolts and designs, not form of attachment.

Robby, no need to write a long discourse on this...I know how you feel and at this stage, you and I will cover more ground person to person. Do you plan to be at the next meeting? If not, can you make the next one? I will make a special effort to make sure we can discuss our views face to face. You are good at discussing how you feel and why, a good attribute to have.

Robby, again I encourage you to write your reasons and feelings related to the fillet welded bolt. If you need help getting your written paper to the ESC, I am happy to help you...as Matt J. would also make sure ESC gets it and so would Kelly Anderson. Like me....go fight the good fight and do the best you can. I really do support you in your right to fight for what you feel is right.

Thanks Robby,

See you soon?

John E. Rimmasch

Matt A:

The most general description is that there is installation and operation distortion of the rear boiler.

The two forces at play are pressure and heat related deformation. Pressure creates as much as a 5mm deformation (on a German Class 44 boiler), especially in the transition zone from the sidesheets to the crownsheet on a radial stayed boiler.

Heat related deformation is partially due to the natural tendency of the sheets to curl inward from being heated - whether from a fire or welding.

Interestingly enough, the two stresses are generally counteracting up to the point where component stresses (ex. staybolts) are exceeded. Then, a direction of permanent deformation becomes more prominent.

The firebox sheets shrink over time. The sidesheets tend to push the wrapper out at the center and give the sides of the boiler some "hog" while the crownsheet tends to sag, particularly in front. Radially stayed crownsheets being particularly susceptible to the later.

On the project we worked on together, we experienced the results of both stresses- which greatly increased my curiosity when I later found Tross's explanation of it - better described in his paper, "New Knowledge of thr Rear Boiler." The wrapper sides were hogged-out which we somewhat improved with elaborate strong-backing. During installation of the firebox, it moved around quite a bit and the welding plan was adjusted continuously as we shot the position of the firebox relative to the wrapper and deformation of the sheets much like Tross did with his observations using a light.

Matt J.

Matt A:

Yes, Exactly.

Matt J.