Studies were conducted to determine the strength and thermal stability of samples of glass with edges obtained by cutting a moving ribbon of float glass by mechanical and laser cutting. The advantage of laser cutting was demonstrated.Brittleness is a problem in using sheet glass. The weakest part of the glass sheet is the edges due to the large number of gross stress concentrators that remain in the edges after cutting the moving ribbon and keeping the degree of its hazardousness unchanged over the entire time of shipment, storage, and use of the glass [1].Mechanical cutting (as the simplest and most accessible) is used in continuous production of sheet glass; it consists of making a median crack with a hard-alloy roller. In order to obtain a quality edge, i.e., a defect-free edge and smooth, shiny end with perpendicular surfaces, the optimum cutting parameters must be rigorously observed. Otherwise, the edge will have a coarse shape with a large number of chips and pits. The transverse bending strength and thermal stability are quantitative criteria for evaluating the quality of the glass edge.Mechanical cutting reduces the strength of the glass by 60% on average. The strength of such glass can be increased by treating the edges. The most common method is mechanical (grinding followed by polishing). However, the strength of the glass increases by approximately 30% [2].A laser cutting unit (Fig. 1) for separating the edges from the moving glass ribbon has now been introduced in the ÉPKS-4000 float line (Saratov Glass Institute Co.). The method of controlled thermal cleavage is used in the unit, and it essentially consists of projecting the beam of a molecular gas CO 2 laser, which provides for local heating (to 350 -450°C) of the cutting line, and feeding an air-water mixture under pressure on the surface of the glass. As a result of the temperature gradient that arises at a small depth from the surface of the glass, a microtrack is formed and causes separation.The edge is separated after the glass ribbon is transversely cut into sheets of the required length with edge cutters. The ends of samples obtained after laser and mechanical cutting of a float-glass ribbon are shown in Fig. 2.The qualitative evaluation with a MIN-8 (´50) microscope showed that both ends are smooth and shiny. However, although a defect-free edge is obtained after laser cutting,

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The results of studies of thermochemical modification of the surface of a glass ribbon in continuous production are presented. It is shown that the deposition of a composite coating, which was developed by the present authors, on the surface of the glass increases its water resistance by an order of magnitude and the mechanical strength about 2-fold. The essence of the proposed development lies in the deposition in several stages of chemical reagents which create on the surface of the glass a transparent film that permits controlling the quality of the float-ribbon.Key words: float-ribbon, thermochemical modification of a glass surface, water-resistance of glass, mechanical strength of glass.Sheet glass has a substantial place among the various materials now used in technical structures and buildings.Owing to its unique property -transparency together with strength and hardness, in a number of cases it cannot be replaced by any other material. The percentage of glass can exceed 80% in modern buildings.In order to guarantee the safety of the glazing of tall buildings and the durability of glass articles in service the mechanical strength of glass, as the main service characteristic of glass, must be increased [1].It is known that the mechanical strength of float-glass is a statistical quantity and is characterized by a large variance of its values (from 20 to 200 MPa). For this reason, the most likely statistical value of the strength or of the minimum values of the strength should be taken as the guaranteed operating characteristics. Such indicators can be introduced into the standards for construction glass.Approximately 40% of construction glass is lost during storage, transportation, and mounting. This is because initially the float-glass is too weak and its strength decreases because of corrosion. Stacked sheets of glass are exposed to the humid atmospheric air and temperature differentials, which can result in the appearance of defects such as surface leaching. For this reason, the water resistance of construction glass is also its service characteristic, and the problem of increasing the water resistance is urgent.The operating properties of sheet glass (strength and water-resistance) are determined mainly by state of its surface.It is well known that because of the particulars of its technology the properties of float glass show a substantial variance along the width of and between the surfaces of the ribbon. This is especially true for the mechanical strength of glass (Table 1).

*Вищий навчальний заклад Укоопспілки "Полтавський університет економіки і торгівлі" вул. Коваля, 3, м. Полтава, Україна, 36014 В статті представлено розроблені принципові технологічні схеми отримання рослинних екстрактів, методом настоювання при постійній температурі з плодів шипшини, обліпихи та калини оброблених у вихровому шарі феромагнітних частинок, а також напоїв, морсів та фізів на їх основі. Принципові технологічні схеми використані при розробці технічних умов "Напої безалкогольні на основі рослинних екстрактів" Ключові слова: технологія безалкогольних напоїв, вихровий шар феромагнітних частинок, водні рослинні екстракти В статье представлены разработанные принципиальные технологические схемы получения растительных экстрактов, методом настаивания при постоянной температуре из плодов шиповника, облепихи и калины обработанных в вихревом слое ферромагнитных частиц, а также напитков, морсов и физов на их основе. Принципиальные технологические схемы использованы при разработке технических условий "Напитки безалкогольные на основе растительных экстрактов" Ключевые слова: технология безалкогольных напитков, вихревой слой ферромагнитных частиц, водные растительные экстракты

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