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Sols et Paysages

Très bel ouvrage, écrit par deux passionnés, détaillant les relations entre paysages et types de sols sur une douzaine d’exemples différents.

Ce livre écrit par deux universitaires est très agréable à lire et explique en détails les principaux types de sols que l’on trouve en Europe et leur incidence sur la végétation et l’utilisation des terrains correspondants.

Cet ouvrage décrit de façon détaillée un grand nombre de sols en croisant les observations sur le terrain, les analyses en laboratoire et en s’appuyant sur la bibliographie et l’expérience des deux auteurs. A partie de ces données sont expliquées la formation du sol et ses incidences sur la végétation et l’exploitation des terrains correspondants.

L’incidence de l’habitat, de l’agriculture, de l’exploitation du sous-sol sont prises en compte ainsi que leurs incidences sur le sol.

Une autre partie traite plus en profondeur les usages du sol qu’ils soient urbains, forestiers, agricoles, viticoles ou autres.

Ce livre est abondamment illustré de photos et croquis.

Il s’adresse à tout professionnel ou futur professionnel dans ce domaine ou dans des domaines proches (agriculture, exploitations forestières ou minières…) mais aussi à toute personne convaincue de l’importance du sol et de l’impératif de le protéger.

 

Sols et Paysages

Types de sols, fonctions et usages en Europe moyenne

Par Jean Michel Cobat et Claire Guenat

Presses polytechniques et universitaires romandes

Lausanne

There are no translations available.

Vente miroiterie Sforza

 

La miroiterie Sforza, installée depuis plusieurs dizaines d'années dans la région grenobloise a été cédée courant juillet à un jeune repreneur.

Main French windows supplier before the merging Bouvet FPPE .

1/Tryba (Atrya)

CA 2017 265 millions d’Euros

 

2/Cetih (Bel M, Swao,  Zilten, CID)

CA 2017 215 millions d’Euros

 

3/Bouvet

CA 2017 162 millions d’Euros

 

4/FPPE

CA 2017 145 millions d’Euros

 

5/Atlantem (Solabaie)

CA 2017 133 millions d’Euros

Very strong growth in Internet sales of wheels for mirrors machines.

Vedip, the first European web site (French origin) Internet sales of Italian wheels for mirrors machines saw its revenues for the second 2019 quarter  increased by more than 67 %.

The strategy developed by Vedip to propose, in partnership with a leading Italian manufacturers of wheels and diamond core drills for glass, very competitive prices  for working only on the Internet, detailed fact sheets with photos, standard wheels made by manufacturers / Machines / Positions, alternative wheels and a telephone support seems to meet the needs of the market in Europe mirrors.

The site already has 1741 tools now online  continues  to improve the technical data of the tools and the number of referenced machinery (over a hundred).

On Vedip you can view the data sheets (with photos and price) of the wheels for the main flat glass processing machines of the market (straight line edging machines, CNC, drills, double edger, chamfering ...) and the most important suppliers (Intermac, Bovone, Glaston, Bavelloni, Lattuada, Schiatti, JANBAC Baudin, Battelino, Denver, Bimatech, Ada, Besana, Bottero ....).

www.vedip.com

Contact : info@vedip.com

Tel 00 33 782 39 43 34.

 

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Glass chemical tempering

 

1/Reasons and advantages for glass chemical tempering

The chemical tempering is used when the thermal tempering meets limits.

Small glass thickness

Even if some suppliers offer now machines able to temper 2 mm thickness glass, the chemical tempering in this case give better results.

 

Curved glass

The chemical tempering is done with a temperature around 400°C which don’t change the glass geometrical shape

This is particularly important when the curved glass has to be laminated after tempering.

The optical quality

Chemical tempering gives better result than thermal tempering when a high optical quality is required.

 

When a more important hardness is required than the one the thermal tempering can supply.

With the chemical tempering it is possible to increase with a factor 4 the hardness in touch with the thermal tempering.

No surface distorsions

With chemical tempering you do not have surface distortion

Processing after tempering

One of the advantages for chemical tempering is that you can process the glass (drilling, edging, polishing, sandblasting, cutting…) after tempering. This is not possible for thermal tempering.

On another side with chemical tempering it is more difficult or even impossible to temper very large glasses, because the maximum furnaces dimensions (around 3200x2200).

More important in case the glass breaks, they remain very dangerous large glass pieces. For this reason, only glasses coming from thermal tempering can be accepted as “safety glasses”

2/Glass thermal tempering characteristics

The idea for chemical tempering (like for thermal tempering) is to put the glass surface under compression to increase strongly the hardness. In the chemical tempering case it is obtained by the migration at the glass surface (between 20 and 100 micrometers) of big potassium cations which take the cations sodium place. Sodium and calcium having similar chemical characteristics this change does not modify the glass properties.

This change is done dropping the glass inside a potassium salt bath between 12 and 20 hours. The salt bath temperature is around 400° Celcius.

Chemical tempering salt bath

 

3/Comparison between thermal and chemical tempering

 

 

Thermal tempering

Chemical tempering

Thickness (mm)

3 à 19

0.5 à 19

Surface compression ( N/mq)

30/70

300/400

Thickness for the compressed area

20% from the glass total thickness

20 to 120 microns

Flexion resistance           ( N/mq)

120/200

250/600

Pieces dimensions when glass breaks

Small pieces

Large pieces

Processing after tempering

 

No

 

Yes (cutting, drilling, edging, polishing, sandblasting…)

 

 

 

4/The main chemical markets

The cost for chemical tempering is much more important than the one for thermal tempering. So the main markets for chemical tempering are where the thermal tempering meets limits or problems.

-Small thickness

-Quality (distortion, optical quality, hardness..)

The markets for chemical tempering is in aviation, space and naval industry, automotive industry, luxury, architectural (bending) and in general when you need nos distortion.

 

5/Conclusion

Chemical tempering is another way to glass tempering, mainly when thermal tempering can bring a proper solution. But to be able to reach the quality required chemical tempering must be done in automatized furnaces and with security and checking systems to supply with productivity the high quality level required.