advertisement


Spontaneous exploding table

martin clark said:
Toughened-glass sheet, suddenly lets-go of the incorporated strain energy, is very definitely a Thing; at a rate around about 1 in 1000 sq.m.

Fundamentally the reason it went bang, is called a nickel-sulphide inclusion.

I could write pages on it, and I've seen far worse 1st hand.
Click to expand...
Is there any way to detect a stress brewing before it causes the glass to shatter?

martin clark said:
sadly not in this case ;)
Click to expand...
I trust you've read them all. Darn.
 
mansr said:
Is there any way to detect a stress brewing before it causes the glass to shatter?
Click to expand...

yes, but only prior to use - to specify a heat -soak of finished panes; as little as 72hrs at c/sub 200degC accelerates the NS inclusion growth such that av expectation of failure goes from c.0.1% to maybe ~40dB below.

Such a reqt is what we write into specification in my day job, depending on what the 'glass is for - balustrades, facades, but esp. overhead - e.g. rooflight use, and so on.
 
martin clark said:
yes, but only prior to use - to specify a heat -soak of finished panes; as little as 72hrs at c/sub 200degC accelerates the NS inclusion growth such that av expectation of failure goes from c.0.1% to maybe ~40dB below.
Click to expand...
So no way to inspect a pane you've already bought, then. Stresses in some plastics can be seen using polarising filters, but I guess glass doesn't have such properties.
 
NIckel-sulphide inclusions remain, yet, a really, really insidious problem.
The offending speck at the point of failure is also small as to never be recovered directly... it is the strain energy deliberately imparted to toughened glass, that pays for the destruction; and that can approach c 150kJ /sq.m or rather more, for some uses.
 
Happened to us with a hifi rack. Glass shelves with stainless steel corner pillars. My wife “heard it go”. No peripheral damage or injuries to humans or cats, just a lot of glass to clean up - “toughened glass”, I presume, cos all the bits were those small squarish bits like when the car windscreen breaks.

Phoned the company to buy a new shelf (nice folks in Yorkshire). They sent me a new shelf, and refused to take any payment for it. Nice one!
 
Bart said:
We were startled by a loud explosion coming from our seldom used dining cum kids playroom this afternoon. I thought someone must have pushed a ladder through one of the windows and when I saw the glass all over the floor, window sills and toys I still thought it was a window, then I noticed the glass table top was missing and realised what had exploded. Apparently it happens occasionally. Mercifully no-one was in there at the time though my two grandsons had been playing in there earlier. It was not a cheap table and came from JL or M&S, 5 or 6 years ago. Something to bear in mind if your in the market for a table!

remove duplicate elements
Click to expand...
We have just the same table from JL, bought 3 years ago. And there was no indication before the boom?
 
mansr said:
I have something fitting that description. Also several glass tables. How worried should I be?
Click to expand...
Failure rate 1 in 1000 sq m, over its lifetime. That's the odds. So a table top 2 sq m has a 1 in 500 chance of going hang over say 20 years. That seems quite high. But nowhere near as likely as being in a serious road accident, say. You have far more than 1 in 500 chance of having one of them in a 20 year period.
 
I had a sparky in my kitchen once nearly have a heart attack - he was doing some work on the sockets lying on the floor and exactly this happened to a 3 x 2 metre skylight in the ceiling.. I was in the room too and it was like a gun shot going off.

We both thought it was an electrical problem, but couldn’t see any fault, until we looked up and saw the shattered skylight! It was the outer pane of glass, so luckily didn’t drop in on us, but wow what a noise.

The skylight company replaced the skylight foc (I guess they have an understanding (or maybe even an insurance) with the glass manufacturer as they know it can happen?!
 
We had a really thick glass tea light holder explode on the dining table, no tealight had been used in it for months.

This is a good video of Prince Ruperts drops exploding


Pete
 
stevec67 said:
Failure rate 1 in 1000 sq m, over its lifetime. That's the odds. So a table top 2 sq m has a 1 in 500 chance of going hang over say 20 years. That seems quite high. But nowhere near as likely as being in a serious road accident, say. You have far more than 1 in 500 chance of having one of them in a 20 year period.
Click to expand...
Don’t forget all my windows, 1 internal door, 2 shower screens and 7 decent sized panes in my staircase!
 
Many years ago we had something very similar happen but with the glass door on the oven. It was even on at the time. I reckoned it was changes in temperature over time that probably caused it. Thankfully it was a one-off experience.
 
You must log in or register to reply here.


advertisement


Back
Top