SU755761A1 - Method of creating gas cushion - Google Patents

Description

The invention relates to methods for creating a gas cushion for maintaining the transported material and can be used in glass processing during heating, molding and transportation of glass. "

The gas pressure under the glass is unevenly distributed, due to its evacuation at the edges of the glass, which leads to a drop in the pressure of the gas cushion. This is especially dangerous in the production of thin tempered glass with a thickness of less than 4 mm, the heat for quenching which is produced to higher temperatures. In this case, viscosity drops sharply in the area of plastic deformations of glass, and glass deformation increases.

A known method of creating a gas cushion by supplying gas through the base of the cushion under the material being transported (1). This method does not allow to achieve an even distribution of gas pressure under the glass due to the unhindered release of gas into the atmosphere from under the edges of the glass at the ends of the cushion.

The closest solution to the technical nature and achievable, eff • with 2

An effect is a method of creating a gas cushion when transporting sheet glass, which includes feeding gas jets perpendicular to it and flattening its pressure under the sheet [2]. This method partially ensures the uniform distribution of gas pressure under glass by changing the cross section of the channels of gas outflow at the base of the pillow, because of their release to the surrounding atmosphere from the edges of the material at the ends of the pillow, the marginal pressure of the gas drops.

The aim of the invention is to increase the quality of glass.

This goal is achieved by the fact that in the method of creating a gas cushion when transporting sheet glass, including feeding gas jets perpendicular to it and flattening its pressure under the sheet, the pressure equalization operation is performed by feeding additional glass jets under the end of the sheet glass perpendicular jets.

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Figure 1 shows schematically a device for implementing the proposed method of creating a gas cushion; FIG. 2 is a graph of gas pressure distribution.

Transported material 1 is located on the gas cushion 2, the gas chamber consists of a perforated base 3 and pressure chamber 4. Gas outflow under pressure occurs through gas channels 5, base 3 of the pillow, perpendicular to the sheet of material (glass) '1. Edge chambers 6, filled with gas under pressure, in which holes or slots 7 are made for blowing gas into the cake cushi 8 cushions under the edges of the sheet material.

When supplying additional gas jets from edge chambers 6, directed at an angle to the main perpendicular jets from gas channels 5, under the ends of the sheet material 1, equalize the gas pressure under it across the entire cross section of the gas cushion 2, since the latter is isolated from the surrounding atmosphere and there is no leakage gas from under the ends of the transported sheet material from glass.

As a result of isolation of the pillow along its ends from the surrounding atmosphere, a decrease in the release of gas into the surrounding atmosphere is ensured, - leveling and preservation of the conditions for the removal and supply of gas of the pillow under the transporting material, i.e. increases the uniformity and stability of the distribution of the gas pressure of the pillow on the material.

PRI me R. On the ends of the transported sheet glass, located on the gas cushion, served jet

'air from the holes of the pipes installed on the ends of the sheet at a distance of 20-5 mm from them. Moreover, the pressure in the air stream was maintained either equal to or greater than the average gas pressure of the cushion under the glass.

The distribution of the pressure P of the gas of the pillow under the glass was measured in a plane perpendicular to the plane of the base of the pillow along the midline, b, between a number of supply and gas-leading channels.

Gas pressure fluctuations of significant cushion areas change its equality, the estimated coefficient! generally £ th uniformity K = K ^ + K ^, where * 'K ^ = is the coefficient of the central

^τησ * uniformity; £ ιχ- ^ρ κ $> / Рср “edge coefficient

uniformity; _{pta <} ~ ^maximum value of gas pressure;

P _cf - the average gas pressure of the pillow under the glass;

p - marginal pressure ga ^r for under the ends of the sheet

glass

In the absence of fluctuations in the pressure of the gas cushion and K ^ = 1 and respectively K = 2.

The curves for the distribution of the gas pressure of the cushion under the glass are plotted in coordinates Р-Ь, for the existing cushions the curve 9 and for the proposed one - 10.

The values of the coefficients of the general uniformity of the theoretical values are,%:

for the curve 9 К = 64, К4--8З and К = 45: for the curve 10-К = 98, К _л = 9 3 and ^α Κ _α = 102, i.e.

coefficients increase for K by 34%, for K / by 10% and for K _g by 57%.

Thus, according to the proposed method, the marginal gas pressure drop is almost completely eliminated, the pressure distribution is significantly improved and approaches the theoretical (K = 98% of 100% of the theoretical K) ..

Therefore, this method can be used to transport material that is particularly easily deformable with high demands on surface quality and geometry, such as heated thin glass.

The use of the method in the manufacture of thin (2-4 mm) tempered glass for the glazing of road transport will give an annual saving of about 2.5 million rubles. So the transition from 5 mm to 3 mm tempered, glass only on passenger cars (approximate level of glass production for 1980 - 3 million m ^g ) will give annual savings in the field of industrial production due to a decrease in the cost of the original glass, energy costs and capital investments over 2 million rubles.

Claims (1)

A method of creating a gas cushion when transporting sheet glass, including feeding gas jets perpendicular to it and flattening its pressure under the sheet, characterized in that, in order to improve the quality of glass, pressure is equalized by feeding additional glass under the ends of sheet glass gas jets directed at an angle to the perpendicular jets. .