Glass Tempering

What is TEMPERING and SEMI-TEMPERING?

The tempered glass, or toughened glass, is obtained by heating the glass at a temperature of approximately 650 ° Celsius, when it starts to soften. The external surfaces are then rapidly cooled, a strong compression being created. The heating process, followed by the cooling one is controlled and the parameters used by this process have a fundamental influence on the quality of the tempered glass.
Its flexural strength is usually four or five times higher than that used in applications requiring the fastening of different metal parts on glass. If it is broken, it fractures in very small, harmless chips, and this is why it is a very safe material.

The semi-tempered glass, or hardened glass, is the glass whose surface is submitted to a compression stress created by a controlled heating-cooling process different from the one used for the tempered glass, in order to provide it with a higher resistance to mechanical and thermal stress, as well as with special breaking characteristics. The semi-tempered glass has another breaking design than the tempered glass.

 Tempering quality assured by TAMGLASS Pro-E 2442. Why Pro-E and not the simple convection?

In 2007, Glass Expert started up the most efficient tempering line for flat glass in Romania. Choosing a state-of-the-art technology and relying on our supplier TAMGLASS - Finland, a highly-experienced partner, we managed to comply with the deadlines set for the commissioning of this investment amounting to over 1.6 mil EUR.

Product quality monitoring software- QMS

QMS - Quality Management System. The glass tempering quality is constantly monitored. With the help of the management system for the tempered glass production process, we can always see if the glass tempering has been correctly performed, according to the standards applicable to this type of product.

Management software for the entire process  - GTMP

GTMP - Glass Tempered Management Process. Because we are interested not only in the quality of the finished product, but also in the entire process from order, delivery and especially after delivery, we have implemented a management system for the tempering process offering a wide range of advantages to our clients. The order processing is electronic, each window is labeled separately, so that each window has a code enabling its monitoring both while it is in the Glass Expert storehouse and especially afterwards.

Tempering according to European standards EN 12150 and EN 1863

Because we have understood from the very beginning the importance of the tempered glass quality, we have worked a lot for this aspect during our trial period. 
Both in the trial period and afterwards, not only did the glass tempering quality comply with the standards, but we also managed to manufacture tempered glass of a quality much higher than the restrictive requirements of the standards. Thus, the evenness deviations were much smaller than those stipulated in the 2 standards.
Due to the fact that we use the glass washing machine with special brushes for Low-E SOFT and the glass is always handled with special gloves (for reflexive or Low-E glass), the occurrence of scratches is practically totally reduced.
We represent the company that understood the fact that the tempered glass is first a safety glass and this is why, according to the standard, we undertook responsibility to mark absolutely any glass manufactured by us and to perform the periodical tests for the products manufactured.
The production control system includes procedures, regular inspections and tests, as described in standards EN 12150 and EN 1863, as well as in the quality manual elaborated upon the receipt of the ISO 9001 certificate issued by the QS Cert certification body.

Characteristics of the tempering lineTAMGLASS Pro-E 2442  

Maximum dimension of the tempered glass: 2480 mm x 4500 mm
We can temper glass with depths between 4 mm and 19 mm.
Any type of glass can be tempered: clear float glass, ultraclear glass, coloured glass, decorative glass, reflexive glass, Low-E Hard and SOFT glass with emissivity of up to la 0.02.
Minimum dimension: 250 mm x 200 mm.
Working capacity: 220 m² / h for 4 mm clear glass and 50 m² / h for 19 mm glass

Heat Soak Test - Test for tempered glass against spontaneous breakages

In order to reduce the risk of spontaneous breakage of tempered glass caused by Nickel Sulfide (NiS) inclusions in normal glass, it is recommended to submit the tempered glass to an additional thermal treatment called "Heat-Soak Test ". This test is regulated by the European Standard EN 14179 and consists in the heating and then cooling of glass according to some curves. It is a destructive process and it thus eliminates most of the glass presenting risks, but it is not able to totally eliminate this type of glass. However, the spontaneous breakage risk is considerably reduced. This treatment is indicated in all situations when the stability of the work, the maintenance of the closures or of the covers and the safety of the users is threatened by the breakage of a hardened glass.

Usage

Glazed elements focusing on the safe operation  

Geamul securizat fiind un geam de securitatea datorita caracteristicilor de spargere este folosit acolo unde se pune accentul pe securitatea in exploatare. Geamul securizat se foloseste in fabricarea diverselor tipuri de usi vitrate de interior sau exterior, vitrine de magazine, intrari in blocuri, mobilier de interior pentru prevenirea accidentelor casnice in utilizare a blaturilor de mese, etajerelor, usilor de mobilier, alte componente din sticla ce intra in componenta mobilierului. O alta utilizare in care se pune accent pe securitate si se foloseste geamul securizat este mobilierul urban, cabinele telefonice, statiile de autobuz panourile de semnalizare, fatade, acoperisuri, parapeti de siguranta, balustrade, etc

In situations when a mechanical fastening element is provided on glass or when the mechanical strength of the glass is important   

Datorita faptului ca sticla securizata asigura o rezistenta la socuri si la incovoiere de 5 ori mai mare decat cea a unei sticle obisnuite este imperios necesara folosirea acesteia in cazul in care exista o prindere mecanica a sticlei. Rezistenta la socuri permite unui geam securizat de 8mm sa suporte greutatea unei bile de otel de 500 g care cade de la o inaltime de 2 m. Cu titlu comparativ, aceeasi bila care cade de la inaltimea de 0.3 m, sparge un geam obisnuit de aceeasi grosime. Pe de alta parte rezistenta la incovoiere a geamului securizat termic este net superioara fata de cea a unui geam obisnuit. Aceasta rezistenta se caracterizeaza printr-o tensiune de rupere la incovoiere minima de 129 MPa. Datorita acestor calitati mecanice geamul securizat este recomnadat in proiecte unde avem usi din sticla, vitraje de dimensiuni foarte mari, balustrade cu prindere mecanica punctuala, inchideri de lift, pardoseli din sticla, etc

  When we need glass with increased strength to thermal stress   

Sticla securizata suporta diferente de temperatura de pana la 250^o C fata de o sticla obisnuita la care o diferenta de temperatura de 30^o C provoaca spargerea ei. Datorita acestei caracteristici a sticlei securizate, de rezistenta sporita la stres termic, se utilizeaza in cazul productiei de aparatura electrocasnica, cuptoare cu microunde, cuptoare de gatit electrice sau cu gaz, a blaturilor de bucatarie pentru protectie la spargere in cazul vaselor fierbinti, pentru usile de semine, cuptoare industriale si alte aplicatii in care se cere o rezistenta ridicata a sticlei la stres termic.