We have spontaneous breakage in the autoclave mainly on 10mm glasses in combination of 10mm Tempered+1.52 SGP+ 6mmTempered, Or 10mm tempered+ 1.52 SGP +8mm Tempered. The reasons for the nickel sulphide are not visible (butterfly type breakage) but the breakage starts somewhere in the middle of the glass though the glasses are with holes the fragment does not start at the hole edge at all. (Fragments are smaller at the edge of the glass than at the center). Can someone give a technical reason to reduce the breakage.
This is something normal... 1 to 2 % of total glass in autoclave has tis kind of breakage. Obviously it depends also who is the float glass producer. For example we have breakages 2times higher with Pilkington glass in comparison with Saint Gobain...
You can not do nothing for avoid this problem :-(
Regards.
Robert
Sorry, if you have breakages with any "butterfly" and you are using SGP, you must check the parameters. You can eplain your problem also to someone from Dupont.
I think you must change some parameters in the autoclave cycle program. Maybe the cooling is too fast. Make some trials.
Robert
Can you take a photograph of the apparent point of breakage and email it to me. If the glass failed from somewhere in the body of the glass, away from an edge or hole, it is most likely to be a nickel sulphide particle.
What is the temperature inside the autoclave?