Metallurgy: Old fire escape tubes.

[Bushranger]

When I was a kid, there was a big move to replace steel  fire escape open stairs on schools with a metal tube-slide.  They worked fine for awhile, but all to shortly, they lost their slipperiness, would not longer work as a slide...kids would get stuck, therefore they lost their function and were abandoned.

As an adult who learned about metallurgy, I attributed the loss of function to the fact that they were constructed from Aluminum and once the protective wax (an assumption it was a wax), wore off, the Aluminum quickly formed its Oxide resulting in a microscopic layer of Aluminum Oxide... which is an abrasive due to the sharp crystalline edges.  

However, someone claims that the tubes were not Aluminum, but were Stainless Steel.  I have performed internet searches to find what metal they were made of, with negative results.  Can anyone attest as to which metal they were actually made of?

 

[MigL]

I have never heard of this.
Where are you from ?

Had they done this at my Elementary school, we would have spent our recess going up the stairs and down the fire escape, instead of playing baseball or soccer ( that's football to you Brits ).

[Bushranger]

Michigan.  All the fire escapes were switched out to the tube types in all the schools in my home town of Ludington, MI.  They all stopped working shortly after they were installed.  At first we shot through them at a dangerous speed...a teacher would stand about eight feet away from the opening and grab the kids to keep them from falling.  They got slower and slower until the kids had to "scoot" down them using their feet to descend.  You can see the tube in the photo I have attached.  That is a plicture of my grade school in the fifties, "Pere Marquette School", in Ludington, Mi.

[Sensei]

On 2/11/2019 at 7:01 PM, Bushranger said:

However, someone claims that the tubes were not Aluminum, but were Stainless Steel.  I have performed internet searches to find what metal they were made of, with negative results.  Can anyone attest as to which metal they were actually made of? 

It depends on producer of particular product.

http://www.escapechute.info/faqs.htm

"2. What are they made of? (....) Each platform is constructed on a modular basis from aluminum with external dimensions of 620mm x 620mm. Any additional construction or support elements to the base plate are made from either aluminum or galvanized steel or stainless steel."

[Bushranger]

Quote

It depends on producer of particular product.

You missed a couple of important details.  My question pertained to the escape tubes that replaced steel stairway fire escapes in the fifties...you can tell by the cars in the picture that it was not modern times.  The link you provided and your comment pertain to modern escape tubes which are not relevant to my question.

[Sensei]

13 hours ago, Bushranger said:

You missed a couple of important details.  My question pertained to the escape tubes that replaced steel stairway fire escapes in the fifties...you can tell by the cars in the picture that it was not modern times.  The link you provided and your comment pertain to modern escape tubes which are not relevant to my question. 

I believe so different producers use different techniques and different materials to make their product, regardless of the time, in which product was made. So if you're interested in, what your product from your photo was made of, go there, take a sample, and examine in mass spectrometer or so.. You will have definite answers just for your particular case.

Without examination of the sample, nobody can give you permanent definite answers about its material composition.

 

[Bushranger]

You still do not seem to get it.  Those fire escape tunnels were only used a short time...then abandoned within a year as they lost function (slipperiness)...they are not what is used in modern times.  As for,  "...going there and taking a sample.", I would need a time machine because the school(s) and the Aluminum (or stainless steel tubes) have been gone for about 50 years or so.  

"...examine in mass spectrometer..."  If I had a sample, I would not need to pull a  mass spectrometer out of my butt ...all I would need is a Oxyacteline torch.  Aluminum melts at about 1200 degrees...way before reaching Red heat, where as steels melt at about 2700 degrees (Red heat).   You knowledge of metals seems to be theoretical rather than practical.

It seems the mystery remains...but, if my theory (the formation of Aluminum Oxide), holds, they were constructed of Aluminum, not stainless steel(s), and were an example of not understanding the properties or requirements when choosing a material.