GLASS-LININGS

The glasses used for coating are of high quality glass of complex composition. They may be defined chemically as alkaline borosilicates and are produced by submitting the raw material to a melting process at a temperature of about 1400 °C.

Their main feature is an extremely high degree of chemical inertness with respect to practically all organic or inorganic substances.

This property is maintained without distinction over a very wide range of temperatures and in contact with both oxidising and reducing compounds, chlorinated or not the only exceptions being hydrofluoric acid and concentrated alkaline solutions at high temperature. 

Since the glass or coating has an amorphous structure and is a dielectric; it is not subject to ageing nor to electrochemical or localised corrosion. The extremely hard, smooth, non-porous surface adds further valuable and advantageous qualities to glass-lined equipment such as resistance to wear, non-stick properties, the prevention of the formation of micro-flora, ease of cleaning and sterilisation and impermeability to gases.

These latter features are of particular value in the pharmaceutical and foodstuffs industries since they are a prerequisite for the purity of the product as well as the durability and immutability of such properties as its colour, smell, taste etc. 

GLASS-LINED STEEL

TYCON technoglass glass-lined steel is a composite material consisting of a coating of glass firmly bonded to the base or support of steel. The bond between metal and glass is obtained by coating the steel surface with a first lining of special glass, the "ground coat", the sole basic functions which is to develop a good union between the glass layer and the metal support.

This is established during a firing process at a temperature of about 900 °C, and is the result of a complex series of electrochemical reactions resulting from the action of "binding" oxides like CoO and NiO. The strength of this bond is even higher than that of the bonds existing within the glass itself. After this initial phase, the glass-lining cycle provides for the application and firing of additional covering layers (usually three or four) of glass, with the aim of providing the lining or coating with their specific and well-known properties and characteristics.

THE TECHNOLOGIES

TYCON TECHNOGLASS GLASS-COATING TECHNOLOGIES

The types of glass for coatings at present offered by TYCON technoglass are all those associated with the Tycon and Technoglass trademarks: the result of many years of study, research, experiments and application and well known to users for their high level of quality.

The chemical and physical properties of the glass are tightly bound to its composition and since the possible combinations of the various oxides that compose it are all but infinite, the creation of formulae for glass of ever better quality and the techniques for the application of the coating are a subject for research that is still always current and alive.

This research is in constant progress in the laboratories of TYCON technoglass. Today, due to their combined technological legacies, it is possible to disclose that a new generation of glass coatings of still better quality will soon be available.

THE STEELS

TYCON technoglass applies its glass linings to three different classes of steel.

CARBON STEEL

This is the material normally used in the chemical industry in general and around which the greater part of TYCON technoglass technology has been developed.

STAINLESS STEEL

The austenitic stainless steel used requires glass of a formula specially developed and perfected after intensive research by TYCON technoglass. Equipment constructed of stainless steel unlike that in carbon- or duplex steel can be used at very low temperatures (as low as -120°C).

DUPLEX STAINLESS STEEL

This is a ferritic-austenitic steel on which can be applied, with some slight modification of the ground coat, the standard glasses developed for carbon steel. Glass-lined equipment constructed of duplex steel has a stainless outside surface that can be polished to a mirror finish, as required by the pharmaceutical industry both for aesthetic reasons and for sterilisation requirements.