Crack in conical flask

[The-Engineer-That-Brews]

Annoyingly I've just noticed that my new 2L conical flask has developed a crack.

I can only assume that this must have happened while I was boiling up and cooling a litre of starter wort in it yesterday, so it's probably my own stupid fault.

I must admit I did feel a little uneasy heating it directly over the gas, but from what I've seen elsewhere this is quite standard practice. Maybe the problem was not that part, but standing it in cold water afterwards for cooling ? Is this inadvisable for Borosilicate glass?

 

[chopps]

I thought that the whole point of borosilicate was that the thermal shock range was large.
100C to tap water should be well within the range, right ? (not an expert)

 

[BlackRegent]

Depending how long you have had it, I would send it back to the retailer as borosilicate glass should not have a problem with rapid heating and cooling due to its much greater resistance to thermal shock. I wouldn't use that again due to the risk of it shattering.

These flasks should be laboratory grade so there should be no problem heating them directly on a gas flame.

I have a 2L and a 5L flask and I routinely plunge them into cold water straight after the boil and I've never had a problem. (I have read it is better practice to leave the flask on the stove for 10 mins to allow it to cool a little before putting into water but I don't bother due to my own impatience).

 

[chopps]

"In terms of temperature, the maximum thermal shock range (the difference in temperatures it can withstand) of borosilicate glass is 170°C, which is about 340° Fahrenheit. This is why you can take borosilicate glass (and some bakeware like Pyrex—more on this below) out from the oven and run cold water over it without shattering the glass. "

Found on Google, so it must be true :)

 

[The-Engineer-That-Brews]

Oh FFS - I really should have read the eBay listing more carefully... right down at the bottom it says:

This is a factory second listing, all products in B grade.​

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The product NOT suitable for heat up function, but works fine with liquid mix and storage. ​

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All products are brand new. ​

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We have found some bubbles at base or side wall while we pack the product, the bubble diameter over 3mm. ​

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Some products maybe slightly over printed, little bit extra graduation mark paints on the glass​

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We will keep update this listing when we find any more B grade glass. ​

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If you need more than the listed quantity, please contact us.​

Grab your bargain.​

Still - while it says there might be bubbles in the glass, it says nothing about cracks (!)