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Glass Column minimum thickness suggestion

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iangineer

Mechanical
Nov 5, 2020
68
I have a 1000mm diameter column made of borosilicate glass 3.3. It is not glass-lined. It is actually just glass. Process is sulfuric acid.

Design pressures and temp = -14.5 psig and 5.8 psig @ 392°F

My question is: How do I go about determining how thin the column can get before it should be replaced? I have access to tensile/bending strength, compressive strength, modulus of elasticity, and Poisson's ratio, but I'm not sure where to go with that.
Speaking with someone involved with industrial equipment glass production, I was told that there is no real tmin. Glass is not a crystalline solid and can just crack without any warning for little reason. Do any of you have any suggestions for where to look for information? I'm about to contact another company that manufactures them to see if they have any info, but wanted to check here first.

Thank you,
ian
 
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Not sure how you would fabricate a 1000mm diameter glass column.
Better go with glass-lined or cladded vessel. Add a sight glass if you really need to see what is inside.
 
Trestala said:
Better go with glass-lined or cladded vessel.

The glass column already exists. It comes in sections about 1 or 1.5 meters long and is supported by an external steel structure that looks like scaffolding. The owners of the column want to know if they should order replacement sections based on thickness, but from what I can currently determine, there isn't a real thickness that the glass can get down to. It's just over time it may become more brittle. I'm still researching, though.
 
In some glass it is the grain boundary/binder phase that is attacked.
Is there any hazing or discoloration?
If there is any measurable thickness loss this is not a good sign.

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P.E. Metallurgy, consulting work welcomed
 
Probably one more for the materials engineering forum as it doesn't sound as though you know what the deterioration mechanism is?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
I don't see any discoloration or hazing.

Thickness readings are taken by UT and they all appear to be in line with the nominal thickness of 14-18mm.

The deterioration mechanism should be the sulfuric acid process which, per the corrosion resistance brochure, shows < 2mm penetration/yr. And, I suppose it would also be gravity since it is not a crystalline solid.
 
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