First let's talk about the main characteristics of glass
A ductile material, but at the same time fragile and dangerous, for these characteristics it is advisable to understand the characteristics.
In this article you will find a glossary, with a simple explanation, of the terms relating to building glass and all the processes that it can undergo to strengthen and embellish it, a convenient purchasing guide.
- transparency
- very smooth surface
- impermeability to liquids to gases, to vapors and microorganisms
- inalterability over time
- sterilizability
- perfect environmental compatibility thanks to the possibility of recycling it infinite times.
USE OF GLASS
-In recent years glass has had a notable growth and is used in the construction field, in the industrial field and in the domestic one: in building constructions (windows, parapets or roofing) in cosmetics, pharmaceuticals or household goods (vases, cosmetics, medicines and glasses ) for decorative elements (objects and chandeliers) in industry in very sophisticated sectors (optical fibres, telecommunications, space vehicles);
GLASS PRODUCTION TECHNIQUES
- There are various glass processing techniques:
Cylindrical glasses mainly made by blowing (cylindrical glass, bottles) The glass in the fluid state is blown into cylindrical metal moulds.
Plate glass it was first achieved with the following methods:
by casting (cast or laminated glass)
extrusion lamination However , they presented poor quality and aesthetic defects. These processing techniques are no longer widely used and we remember them only for the production of particular or decorative glass:
printed glass (an embossed design is printed on the surface)
wired glass (a metal mesh is inserted inside it and is used for safety in the underlight areas of the parapet of the windows)
ornamental glass
FLOATING FLOAT GLASS With the production process invented by Alastair Pilkington, 90% of the flat glass produced is with the floating system called float glass.
The procedure is very simple and revolutionary:
1) To the raw materials, appropriately weighed and mixed, consisting of silica sand (the vitrifier), soda (the flux), lime (the stabilizer). The vitrifiable mixture is then introduced into an oven where it is melted at a temperature close to 1550° C
2) the liquid glass at around 1000° is poured onto a bath of molten tin, where, having a greater density, it floats.
3) floating on the pond, it spreads along the surface forming a smooth surface on both sides
4) as it "walks" on the tin it cools and solidifies, forming a continuous ribbon
5) heated again, the glass is "fire-polished", two perfectly parallel surfaces are formed as if by magic;
TYPE OF GLASS for construction
-We will focus on GLASS for construction, a versatile component used in many fields in construction, the main types are the following:
tempered or toughened glass
coupled or laminated glass
armored glass
insulating glass structural glass
TEMPERED OR TEMPERED GLASS .
It is a glass obtained from a normal sheet of Float Glass, heated at a high temperature until the structure softens.
It is abruptly cooled with jets of cold air.
Tempered glass is obtained through tempering, which is nothing more than a heat treatment that gives the glass particular characteristics of resistance to impacts, thermal shocks and bending.
Industrial process to obtain tempered glass.
1) The sheet glass is placed in an oven heated to the glass transition temperature of 640 °C
2) The glass is cooled abruptly by jets of air. In this way the external surface hardens, while the internal part which is still hot and viscous cools more slowly
Particularly used in construction, toughened or tempered glass is used in safety situations and where high temperature resistance is required.
Tempered glass is a perfect material for creating architectural elements without a load-bearing structure, such as doors, booths, shower cubicles and exposed railings in glass only.
When tempered glass breaks, the tensile and compressive forces instantly cause cracks in all directions, so that the glass shatters into many small dull splinters, instead of breaking into a few sharp and much more dangerous pieces, as in the case of normal glass.
COUPLED OR LAMINATED GLASS
Laminated glass has a higher thermal and acoustic insulation capacity than monolithic glass of the same thickness.
Laminated glass is particularly used for the construction of shop windows, shatterproof windows and doors, armored doors, post office and bank counters.
In the event of breakage, the intermediate plastic layer keeps the fragments in position and the glass, even if hit violently, can crack, but is unlikely to break through. The PVB layer also gives the material greater acoustic insulation power and reduces ultraviolet transparency by 99%. A laminated glass is obtained, which increases the solidity of the glass itself and in the event of breakage, prevents the dispersion of splinters .
Layered crystals are also used in all situations in which a possible fall or breakage of the sheet could cause damage to things or people.
Industrial process to obtain laminated glass.
By coupling the glass with 2 or more glasses with a sheet of plastic adhesive (PVB or Polyvinyl Butyrate), under the combined action of heat (about 70° C) and pressure which have the purpose of expelling the air and joining the materials.
EXTRA-CLEAR GLASS
Extra-clear glasses are obtained by eliminating approximately 90% of the iron oxide, with this process the glass remains much more transparent than float glass.
It is not always better to use extra-clear glass as if there are radiation problems it does not shield the sun's rays, allowing more light and heat to pass through.
ARMORED GLASS
Armored glass is safety glass and is made up of a combination of at least 3 sheets of glass and 2 sheets of adhesive and transparent PVB.
Armored glass increases the degree of active safety (the ability of the glass to prevent intrusions) and passive safety (in the event of breakage, the armored glass does not cause damage to things or people).
They are usually installed in residential environments, public buildings, banks, commercial activities and shops.
LEADED ANTI-X-RAY GLASS
Leaded and x-ray safe glass is an excellent solution for hospital medical applications, mainly suitable for shielding nuclear medicine environments.
The anti-x glasses are made with a different content of Barium and Lead and offer optimal shielding against radiation.
Thicknesses vary from
- 8 with a lead content of mm. 1.7
- 10 with a lead content of mm. 2.1
- 12 with a lead content of mm. 2.5
- 15 with a lead content of mm. 3.1
- 18 with a lead content of mm. 3.8
- 20 with a lead content of mm. 4.2
- 25 with a lead content of mm. 5.3
INSULATING DOUBLE GLASS
Insulating glass is particularly used in construction, there are significant advantages from an economic and also ecological point of view.
Insulating glass, also called double glazing, in addition to increasing thermal insulation performance, is extremely useful for total acoustic insulation.
Industrial process to obtain double glazing.
Made up of double or triple glazing, they are made with two or more glass sheets joined together by a spacer frame made of aluminium. The two glass plates are separated by a layer of air or gas; argon, krypton, which aim to increase thermal and acoustic insulation.
GLASS WORK
There are many processes that can be carried out on glass
Lacquered glass
Positive sandblasted glass
Negative sandblasted glass
Frosted glass
Engraved glass
Engraved and colored glass
Engraved glass with gold application
Silk-screened glass
Furthermore, it is possible to create any type of hole or slot cut on the glass using laser machines.
TEMPERED AND LACQUERED GLASS DOORS
It is a tempered glass, to which mineral pigments in RAL colors are applied, totally or only partially on the surface. Painted or lacquered glass is produced by painting one of the faces of flat glass with a ceramic layer which, when treated at high temperatures, attaches firmly to the surface and does not fade.
POSITIVE SANDBLASTED GLASS DOORS
Sandblasting is perhaps the oldest method of glass decoration and is based on the frosting of the glass using corundum, which has now replaced sand, fired by a compressor at around 6 atm.
Thanks to particular masking it is possible to obtain a design with a decorative effect on the surface of the glass.
Positive sandblasting, the decoration is directly sandblasted onto the slab, taking on a lighter colour
NEGATIVE SANDBLASTED GLASS DOORS
Negative sandblasting, usually carried out on transparent glass, the entire sheet is sandblasted with the exception of the decoration which remains transparent.
SATIN GLASS DOORS
For the etching process, hydrofluoric acid is used, the only one capable of affecting the glass, obtaining a satin finish that makes it more resistant to stains than simple sandblasting.
Uniform etching allows you to obtain a homogeneous surface similar to silk, pleasant to the touch, known as "satin".
TRANSPARENT ENGRAVED GLASS DOORS
The engraving on the glass is a deeper sandblasting, which creates a transparent groove on the glass. Each process is carried out manually and makes each glass unique.
ENGRAVED AND COLORED GLASS DOORS
Initially, a deep incision is created by sandblasting. subsequently a scratch-resistant resin in RAL colors is manually applied. After drying, a transparent epoxy resin is applied to make the gilding resistant over time.
ENGRAVED GLASS DOORS WITH GOLD APPLICATION
Engraving and 24K gold leaf application.
As the first processing phase, deep sandblasting is carried out which creates a groove on the glass. Subsequently, a very thin sheet of pure 24 carat gold is manually rolled out and glued.
After drying, a transparent epoxy resin is applied to make the gilding resistant over time.
SILKSCREEN GLASS DOORS
The silk-screen printing technique that is used to reproduce images or documents, the printing takes place by means of a cliclè or printing frame where an ink is made to flow which passes through the meshes, depositing itself on the glass, reproducing the desired design.
The main uses of screen printing are art reproductions, paintings, signs, drawings. Lately with new laser or micro inkjet printers this process has become cheaper and faster.
GLASS COLORS
Glass is normally transparent depending on the substances dissolved in the glass determine the color tone.
The paste colored glass takes on different colors based on the minerals added.
Blue-green glass with added iron oxide
Purple red glass with added copper oxide
Blue-green glass with added copper oxide
Bronze colored glass with addition of cobalt, selenium and iron Intense blue colored glass with addition of cobalt oxide
Gray colored glass with addition of cobalt, selenium, iron and chromium
Purple-pink glass with the addition of colloidal gold and tin
Yellow-orange-red glass with the addition of colloidal selenium and cadmium
HOW MUCH DO GLASSES COST
The cost of glass varies greatly depending on the type of glass used, the thickness of the glass itself and the decorations to be created, in short the cost varies
from a minimum of €25.00 square meter to a maximum of €400.00 square meter
Let's consider a thickness of mm. 8
FLOAT GLASS from a minimum of €25.00 per m2.
TRANSPARENT TEMPERED FLOAT GLASS €100.00 per m2.
LAMINATED FLOAT GLASS €25.00 per m2.
SATIN TEMPERED FLOAT GLASS €140.00
TRANSPARENT TEMPERED FLOAT GLASS WITH SANDBLASTING €200.00 per m2.
SATIN TEMPERED FLOAT GLASS WITH SANDBLASTING €210.00 per m2.
TRANSPARENT TEMPERED FLOAT GLASS WITH ENGRAVING €250.00 per m2.
SATIN TEMPERED FLOAT GLASS WITH ENGRAVING €260.00 per m2.
TRANSP TEMPERED FLOAT GLASS WITH COLORED ENGRAVING €280.00 per m2.
TEMPERED SATIN FLOAT GLASS WITH COLORED ENGRAVING €300.00 per m2.
TRANSPARENT TEMPERED FLOAT GLASS WITH SILKSCREEN PRINT €420.00 per m2.
LACQUERED TEMPERED FLOAT GLASS €320.00 per m2.
For colored glass there is an increase of 10 to 20% to consider
EXTRACLEAR GLASS HAS A COST INCREASE OF ABOUT 30%
GLASS DOOR PRICES DIFFERENT SOLUTIONS
Tempered glass door lacquered in RAL colors €700.00
Positive sandblasted satin tempered glass door €600.00
Negative sandblasted transparent tempered glass door €600.00
Satin tempered glass door €500.00
Engraved tempered glass door €700.00
Engraved and colored tempered glass door €800.00
Engraved tempered glass door with gold application €1500.00
Silk-screened tempered glass door €900.00
* indicative prices to be calculated, VAT and SHIPPING
HANDLING AND TRANSPORTING GLASSES
A glass door, especially if very large, can break even due to simple bending.
To lift, move and/or transport a sheet of glass, it is always a good idea to have two people:
- The glass plate must be lifted from the corners at the same time, always being very careful not to hit the edges.
To handle the glass we recommend proceeding as follows:
1) The slab must always be held sideways;
2) If you need to place the glass temporarily, you can place it against a wall, always on its edge, and place it at an angle.
3) Normally it is preferable to place the long side on the floor and the wall with the interposition of thick cardboard or soft material.
OUR TIPS ON HOW TO CLEAN GLASSES
Window cleaning is undoubtedly one of the most demanding activities. It can sometimes be a long operation and is often also difficult.
However, this type of cleaning can also become practical and quick if you follow some important precautions.
In most cases, however, homemade remedies with natural ingredients such as vinegar, water, alcohol and bicarbonate prove to be much more effective and above all also allow savings from an economic point of view.
Prepare 1 liter of warm water, half a glass of white wine vinegar and half a glass of alcohol: pour the solution into a "squirt bottle", rinse and dry the glass.
To avoid the formation of specks and rings after drying the glass, it is necessary not to use water with a high concentration of limestone and not to wash the glass when the sun is shining.
For cleaning small or medium-sized surfaces you can choose between microfibre or chamois cloths, or newspaper, usually the most used, as it guarantees thorough cleaning, without streaks and residues.
If the crystal is frosted, decorated, engraved, reflective or printed: dust the glass with a soft cloth; wash with water mixed with neutral, silicone-free glass cleaning products; rinse and dry immediately with a clean, soft cloth, preferably microfibre, always wiping it in the same direction.
If the crystal is sandblasted: dust the glass with a soft or semi-hard brush, made of natural bristle or synthetic fiber (attention: the brush must not be abrasive or metal); wash with water, mixed with neutral or Marseille soap, dissolved in water; rinse and dry immediately with a microfibre or chamois cloth, always wiping it in the same direction.
For deeper cleaning, moisten a cotton cloth with RIO AZZURRO, pass it over the area to be treated and rinse with water. Be careful not to use on engraved, colored or gilded glass.
If the crystal is enamelled: dust the glass with a soft, clean cloth; wash with a solution prepared with 70% warm water and 30% alcohol; rinse and dry immediately with a clean, soft cloth, preferably microfibre, always wiping it in the same direction.
It is important not to use chemical products or abrasive pads which could damage or scratch the enamelled surface.
Another product to use, but only in extreme cases, is RUBOUT, be careful not to use it on engraved, colored or gilded glass.
RubOut is a special cream that removes limescale, rust and mineral residues from all types of glass and shiny surfaces, even from glass that has not been cleaned for years.
The product must be used pure in small amounts spread on the surface with a white rectangular pad, left to act for a few minutes and then rubbed in a circular manner with the same pad.
Removes residues without damaging surfaces. Before applying RubOut always carry out a test.
Do not use on glass with film.
You can buy Rubout on AMAZON
https://www.amazon.it/RUB-OUT-DETERGENTE-PER-VETRI/dp/B009EU9Y5O
DISPOSAL OF BROKEN GLASS, THE HIDDEN COSTS
If you have to replace a frame with glass applied, the issue of disposing of the old frame must also be considered. It is important to also define the costs that will be borne by the seller. Otherwise, it may happen that you will have to personally take the old frame to the landfill, with the related inconveniences.
Have the seller issue a certificate of regular disposal of the fixture, to avoid a complaint for abandonment of waste!
THE GLASS BREAKS
Regarding the safety of glass, it can be stated that thermally tempered glass breaks into small fragments in the event of breakage, so much so that it is called injury-proof glass. based on the UNI EN 12600 standard.
The most delicate points of a glass sheet are the edges.
Even if the glass is excellently tempered, the weak point is the edges and if an edge is hit with an object, or in the case of a glass door, is placed on an edge you can be almost certain that the glass will break.
The quality of the tempering is associated with the type of fragmentation obtained, in the photo you can see the breakage into small fragments and it is clear that the tempering was carried out to perfection and that despite the tempering giving the glass 5 times more strength superior to float glass, the blow that the glass suffered was very strong, so much so that it caused the entire glass to collapse, rendering it into small, not very sharp parts.
MECHANICAL PARAMETERS OF GLASS any breakages
The quality of the tempering is associated with the type of fragmentation obtained; in the photo of the small fragments, it is clear that the tempering was carried out to perfection and that despite the tempering giving the glass a strength 5.5 times greater than float glass, the blow that the glass suffered was very strong, so much so that it caused the entire glass to collapse.
The thermal tempering process to which the glass is subjected causes a thermal shock which hardens the structure of the glass and makes it more resistant. In the event of the presence of defects in the molecular structure of the glass already in the tempering phase or within 24 hours, the glass breaks during the cooling phase.
Besides the merits and advantages of glass, there is an indisputable disadvantage: breakage!
Tempering glass improves its resistance, but it still BREAKS! excluding the obvious case of impact, it breaks when subjected to tensile stress.
Tempering improves break resistance of the glass, increasing its ability to withstand stress produced by accidental or systematic events, which would lead to breakage.
The resistance to breakage of the glass with the tempering process increases the resistance to the absorption of accidental shocks by 5 times.
The breakage of tempered sheets never occurs in an inexplicable way and there is no such thing as "spontaneous breakage", the breakage is the result of a multiplicity of causes that create the conditions for the glass to shatter.
Even a stress applied to a limited part can cause breakage, similarly a very intense stress can be critical even for an optimally tempered sheet.
GLASS AND EUROPEAN STANDARDS
Over time we have tried to standardize the characteristics, referring to European standards.
The following table lists the main mechanical and thermal parameters [Source: UNI EN 572-1]
Glass plays a very important role, in this regard the legislator wanted to define with rules the characteristics that producers must comply with. The main reference standards are the following:
UNI EN 12150-1:2001 Glass for buildings - Thermally toughened sodium-calcium silicate safety glass - Definition and description
UNI EN 12150-2:2005 Glass for buildings - Thermally toughened soda-lime silicate safety glass - Part 2: Evaluation of conformity/Product standard.
Technical standards on fixtures with applied glass
- UNI EN 947:2000 Hinged or pivoted doors - Determination of resistance to vertical load
- UNI EN 948:2000 Hinged or pivoted doors - Determination of resistance to static torsion
- UNI EN 949:2000 Windows and curtain walls, doors and shutters - Determination of the resistance of doors to impact with a soft and heavy body UNI EN 12046-2:2002 Operating forces - Test method - Doors
- UNI EN 1191:2002 Windows and doors - Resistance to repeated opening and closing - Test method
- UNI EN 1192:2000 Doors - Classification of mechanical resistance requirements UNI EN 1527:2000 Accessories for doors and windows - Accessories for sliding doors and folding doors - Requirements and test methods
- UNI 10807:1999 Prefabricated railings, balustrades or parapets - Determination of mechanical resistance to dynamic loads
- NF P01–013:1998 resistance to dynamic loads pendulum test according to standard
- UNI 10807:1999 Prefabricated railings, balustrades or parapets - Determination of mechanical resistance to dynamic loads DM INFRASTRUCTURES OF 14/01/2008 LINEAR HORIZONTAL LOAD
- INFRASTRUCTURE DM OF 14/01/2008 LINEAR HORIZONTAL LOAD
