Wednesday, July 4, 2018

How It's Made

Amazing series on YouTube.  I was watching a segment about how window glass isa made perfectly flat.   I knew the old technique for window glass was not very good.  If you can see distortions in house glass, it usually means it is pre-1920.  I did not know the current method involved floating molten glass on molten tin, cooling it until the tin is hard.

I also enjoyed a United Airlines promotion film from 1950 about their Hawaii service in the Boeing 377, which was a double decker.  I had forgotten how lovely it was to have airlines serve a decent hot meal in the air.   I have very positive memories of a Salisbury steak dinner served in about 1981.  Most of the seats on the plane were empty.  Those were the days.


pigpen51 said...

I worked in a place that made steel for the investment cast industry. We also made steel for the aerospace industry industry, melting steel under high vacuum. I worked there for 35 years, and so did every job in the place at one time or another, including the lab.
I ran the vacuum furnace that made steel for jet engines like Rolls Royce and Pratt Whitney, and one of the guys that I worked with once was from Texas where he worked in a place that made glass, following the method you describe. He said it was a good place to work, but it was also hot, as was the steel melt facility that we worked at.
It is pretty amazing how mankind comes up with ways to do things in better ways, to solve problems while improving performance. There are some pretty ingenious people in this country, as well.
As you can imagine, steel is weak at the grain boundaries, where it cools. So our Vice President of Technologies figured out how to make a vacuum melted steel called a single crystal, that formed with no boundaries when solidified. It is used in the most critical hot parts of a jet engine. The man originally is from England, now a U.S. citizen, and came up with how to do it in his bathtub.
The hotter a jet engine can run, the more efficient it is. But the closer to the melting point of the metal, of course, the closer to failure the part gets. So by making these high temp parts, like blades and vanes, out of what are called super alloys, that hold their strength closer to the point of failure,they are able to run them at higher temps, and thus able to run them more efficiently.
To do this, they control any trace, or tramp, elements, very carefully, to ensure absolute chemical composition. Trace elements that can be harmful include oxygen and nitrogen, thus the need to melt this type of metal under a high vacuum. We got as low as less than 10 microns of mercury, which is pretty much close to outer space vacuum.

Andy in San Diego and Elsewhere said...

How it's Made is like nerd-crack. It's running constantly on the Science channel.

Mauser said...

As I was searching for that video, I ran into the similar one they have where they ran the DC-6. The meal was even better.