The endowment of traditional materials with special characteristics has long been a common practice. Products with improved chemical protection properties, increased heat resistance and hardness are used in energy, engineering, construction materials and in other areas. At the same time, narrow areas of application of the same fire-resistant products do not go unnoticed. So, borosilicate glass is widely used in medicine, the dishes from which are distinguished by ease of use and a considerable range of protective properties.
Glass composition
The technical and physical qualities of materials are determined by two factors - the processing technique in the production process and the components of the primary elemental base. By and large, this glass is a representative of a group of ordinary silicate materials, which are based on oxides. This is a basic list of components, including sodium carbonate, silica sand and calcium oxide, i.e. limestone. At the same time, borosilicate glass is distinguished by the presence in the composition of another element, which largely determined the non-standard qualities of the structure. Boron oxide is added to the general silicate composition, which ensures the resistance of the glass to temperature extremes. Of course, the composition of modern glasses is not limited to this, since technologists modify the sets of elements, focusing on the specific requirements for the final products.
Glass manufacturing technology
In general, the production method of borosilicate material is similar to the technology for the production of ordinary glasses. In the process of cooking the main melt, furnace units with a temperature of more than 1300ºC are involved. The liquid mass is molded on special metal panels. According to the technique of the float process, borosilicate sheet glass with specified dimensions is produced. The peculiarity of this method is that the resulting sheets are not cut and are not adjusted at all, but are used by the end user in finished form.
Of these glasses, glass units, doors, and, in some cases, fire walls, are subsequently assembled. A considerable proportion of industries involved in the production of such glasses focuses on the manufacture of finished dishes. These can be test tubes, vessels, bowls and other items used in medicine and technical support of research centers. Special equipment is used for the mechanical cutting and polishing of ingots, from which laboratory glassware in various forms is subsequently obtained. Actually, the main difference between the manufacture of this material from conventional silicate analogues is the organization of the working process at higher temperatures.
The main characteristics of glass
Glass of this type is beneficial in many properties and operational characteristics. First of all, it is a wide temperature range of the environment in which glass can be used. As standard, the material withstands frost up to -80ºC and heat at 525ºC. From the point of view of operation in laboratory conditions, resistance to chemical influences comes first. These are the qualities that a medical test tube is endowed with. Borosilicate glass with its inertness is sufficient so that the user can reliably protect the contents from acids, salts, alkalis and organic compounds. The mechanical resistance of this material is also noted. Since the density coefficient of a borosilicate base is higher than that of silicate glasses, it is better protected from the risk of physical damage. In addition, strong thermal effects do not destroy the surface of the glass into small fragments, but burst panels in which blunt and safe edges are formed.
Sizes and format of release
Specialized dishes are usually produced to order laboratories and medical enterprises. However, the production of sheet materials provides for some production standards. In particular, the thickness of the glass panel may be 6-12 mm. Moreover, the error usually does not exceed 0.3 mm. The maximum format in which sheet heat-resistant glass is produced is presented in a size of 150x300 cm. But, again, by special order, many enterprises, if they have technological capabilities, expand these manufacturing parameters. As for the minimum values, it is customary to consider the 10x10 cm format as the smallest unit of production of such glass.
Fields of application
As already noted, the characteristics of the material are best suited for use in laboratories, in equipping medical rooms, etc. For such purposes, manufacturers produce flasks, vessels, test tubes and other products. The vacuum tube of borosilicate glass, in addition to special physical characteristics, also has a design feature. Although outwardly it may seem that this is one tube, in fact there are two of them and they form a vacuum. This type of sheet glass also finds its application. It is usually used as partitions, in optical technology and when equipping premises with protective barriers.
Fire borosilicate glass
Fire resistance qualities are especially appreciated - one of the key characteristics of borosilicate material. Manufacturers produce special panels for glazing and the device of door and window paintings with enhanced protective qualities. In this case, for example, spider glazing is distinguished not only by refractory properties, but also by mechanical resistance. The standard plastic window systems are also equipped with heat-resistant glass, which provides thermal protection. Fire- resistant materials for decorating ceiling and floor surfaces are also becoming widespread.
Glass Restrictions
Despite a wide range of advantageous technical and operational properties, borosilicate products have some limitations on their use. As for interaction with an open flame, the material is able to hold fire for no more than an hour. This nuance does not allow the use of such glass in rooms with increased fire safety requirements . There are restrictions for other applications. In particular, laboratory glassware does not withstand contact with hydrofluoric and hydrofluoric acids. Negative effect on test tubes with flasks and caustic alkali, the effect of which is supported by high temperature. The extreme temperature regime itself does not destroy the glass, but sudden changes do not allow the material to adapt the structure in a timely manner.
Conclusion
Borosilicate glass products should not be considered as a special material for targeted protection against chemical influences and fire. We can say that these are secondary and even auxiliary characteristics that traditional products are endowed with to increase practicality. Nevertheless, borosilicate glass, in addition to protective qualities, retains such properties as transparency and light transmission. Therefore, the combination of mechanical resistance, fire resistance and translucency allows us to consider the material as unique. At least, such is laboratory glassware, which, in addition to the above characteristics, also has optimal inertness.