When is lab glass 'lab glass'?

[takai]

When it does this under heat/cold change:

Labelled as Schott GL45, but certainly not. Unsure where it came from though, i bought up a few different sets of lab ware last year.

 

[seamad]

was the cap screwed on ? If so the vacuum may have broken it.

 

[takai]

Only a thread, loose enough to allow air to come in.

Second one with the same markings has cracked as well. FFS, why bother paying good money for glassware. May as well get the knock off stuff if you cant heat/cool rapidly.

 

[TheWiggman]

Depends what you mean by 'lab glass'. GL45 has a guaranteed resistance of 160K difference from thermal shock so there's no way this should have occurred. Is there a chance they could be counterfeit?

 

[seamad]

Genuine schott has retrace number printed on the glassware, maybe contact them ?

 

[takai]

Well given it is in the bin already fat chance of that.

The $5 kegking 'Erlenmeyer' flask did the same process without a hitch.

 

[GalBrew]

Well given it is in the bin already fat chance of that.

The $5 kegking 'Erlenmeyer' flask did the same process without a hitch.

I have been using the same KK flask for 4 years. Boiling my extract directly on the stove and cooling straight in the sink. Never had a problem.