5 projects where you should consider heat soaking your toughened glass

5 projects where you should consider heat soaking your toughened glass
Photo source
While toughened glass is much harder to break than annealed glass, when it does break it crumbles in its entirety into small, harmless pebbles.

Toughened glass is one of the most widely used glass products in the world. Up to five times stronger than standard annealed glass, it is also more thermally stable, withstanding sudden temperature changes which would cause plate glass to crack.

While toughened glass is much harder to break than annealed glass, when it does break it crumbles in its entirety into small, harmless pebbles. In most instances this means it is a far safer product to use, as there are no razor-sharp shards left behind.

However, the crumbling characteristic of toughened glass can also have a downside.


Why would heat soaking be necessary?

Toughened glass is produced by a process called thermal tempering, where float glass is heated up to its transition temperature of around 650°C, when it begins to soften.

It is then rapidly cooled, so the surface of the glass is cool, while internally the glass remains hot. This creates centre tension in the glass.

On rare occasions, this tempering process can cause problems if the plate glass used has microscopic inclusions within it.

Nickel sulphide particles formed in the production of the plate glass will cool down at a different rate to the rest of the glass. As they cool, they increase in volume, causing additional stresses within the toughened glass.

The result can be that the toughened glass shatters, seemingly spontaneously.

While this is rare, when it does happen it can cause major inconvenience and be expensive to replace.

The heat soaking process serves to ‘weed out’ any sheets of toughened glass that are liable to spontaneous breakage. Sheets of toughened glass stacked in the heat soaking machine are warmed to 290°C for several hours.

Any nickel sulphide particles present will be forced to transform to their low-temperature state during the process, causing the toughened glass to shatter in a controlled environment rather than on-site weeks, months or even years after installation.

Heat soaking will identify more than 95% of problem panes.


So when should I consider heat soaking?

The heat soak process adds a premium to the price of toughened glass. But when the potential risks, cost and inconvenience of replacing shattered panes on-site outweighs this premium, it is a process worth considering.

Here at Tufwell Glass, we recommend clients consider heat soaking for the following applications:

1.       Frameless glass balustrades: If a frameless, cantilevered or structural glass balustrade shatters, the absence of any kind of frame or handrail could pose a significant safety risk

2.       Infill glass balustrades: If fallout from a glass balustrade is going to be a significant issue, for example if the balustrade is on an overhead balcony or a mezzanine floor, we would recommend heat soaking.

3.       Exterior glass doors: A shattered toughened glass door would pose a significant security risk to both commercial and domestic sites.

4.       Sloped overhead glazing: Again, the potential risk of shattered toughened glass falling on people from overhead glazing makes this a candidate for heat soaking.

5.       Glass spandrels: Shattered toughened glass spandrels could pose a risk to the public from falling glass, as well as being a major inconvenience to replace.

Tufwell Glass offers the option of heat soaking toughened glass at our factory in Crawley.

600450 5 projects where you should consider heat soaking your toughened glass glassonweb.com

Others also read

New project, old client: Britplas bolsters mental health project pipeline
Britplas have been appointed to supply the windows and glazing package to Mersey Care NHS Foundation Trust’s new mental health facility in Southport, in the continuation of a relationship which started 12 years ago with the installation of the first ever Safevent windows.
Sapa's STII Door goes from strength to strength
The STII commercial door has been well received by the market and sales continue to grow across all sectors.
122 Leadenhall - 'The Cheesegrater'
Designed by Richard Rogers of Rogers Stirk Harbour + Partners, 122 Leadenhall has become an iconic part of the London skyline.
Astraseal offers customers the future of flush with new Alitherm 800
Well-respected trade and commercial fabricator Astraseal has created new, valuable opportunities for their customers nationwide with the launch of Alitherm 800, the brand-new aluminium flush casement from Smarts.
Aluminium fabricators due more choice & support | Window Ware
Find out how Window Ware is putting itself ‘in the frame’ to meet rising demand for aluminium door and window hardware with a growing product range and specialist knowledge.
Virtuoso launches first aluminium frame for composite doors
Virtuoso Doors has pulled off yet another first in the composite door arena with the announcement that its range of composite doors is now available in an aluminium outer frame from REAL Aluminium.

From industry


Trex Commercial Products
Wrightstyle Ltd.
Trex Commercial Products

Add new comment