SU1532774A2 - Arrangement for automatic dispensing of liquid refrigerant - Google Patents

Abstract

This invention relates to a cryogenic technique and allows for improved performance. The device contains a refrigerant vessel 1 with a discharge piping 2, on which a pneumatic valve 4 is installed, made in the form of a sensor tube 5 located in the consumer tank 6. The adsorbent 10 is placed in the internal cavity of the sensor tube 5, and the outer surface is coated with a layer of capillary-porous material 11. A layer of capillary-porous material 11 reliably protects the sensor from vapor cooling of a cryogenic liquid; at the same time, the same layer does not prevent the sensor from cooling when immersed in liquid, because of a stepped eliminated refilling consumer and charging time is shortened. 1 il.

Description

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j The invention relates to a cryogenic technique, in particular with respect to systems and devices intended for storage and delivery of liquid refrigerant toB to a consumer, and can be used in the automatic charging of consumers with a metered amount of refrigerant.

The purpose of the invention is to increase productivity.

The drawing shows a diagram of the device (| tva for the automatic dispensing of liquid refrigerant.

The device contains a refrigerant vessel 1, a discharge pipe 2, a drain pipe 3. A pneumatic valve 4, normally closed, is installed in the discharge pipe 2. Pneumatic valve 4 is made in the form of a sensor tube 5, located at the calculated level in the consumer tank (Dewar vessel) 6, and the bellows 7, which are filled with a pressurized gas Ј jieHbi, also of the locking element 8 and the seat 9.

An adsorbent, for example, zeolite 10, is placed into the internal cavity of the sensor tube Jp, Ј the outer surface is provided with a coating in the form of a layer of capillary-porous Material 11, for example, metal pipes, metal ceramics, glass wool, etc. A valve 12 is installed on the drain tube.

 The device works as follows. In the initial position, the valve 12 is opened, in the vessel 1 there is a refrigerant, for example liquid nitrogen.

To start the device in the mode of automatic dispensing of the metered amount of Refrigerant, valve 12 is closed, pressure | is increased in vessel 1 | by evaporation (or pressure is increased using a special device), and liquid nitrogen is distilled through pipeline 2 to consumer 6 (Dewar vessel ). In this case, the pneumatic valve 4 is open, i.e., the locking element 8 is depressed from the seat 9 by the gas pressure in the bellows 7 and the sensor tube 5. The refrigerant entering the warm consumer is rapidly evaporating. The refrigerant vapor intensively blasts the sensor tube 5, however, they can cool down because the layer of capillary-porous material 11, which reliably insulates the sensor reliably, prevents this (reliable thermal insulation is achieved due to

very low thermal conductivity of capillary-porous materials. Thus, the thermal conductivity of glass wool is 0.035 W / mH Hgrad, i.e. more than 20 times lower than that of

source material - glass, in which the thermal conductivity is 0.74 W / m-hail). As soon as the refrigerant level in the consumer reaches the design value and the sensor tube o dips into liquid, the pressure in the sensor tube and bellows 7 decreases sharply, as a result of which the locking element 8 is pressed against the saddle 9, the pneumatic valve 4 is closed, and the refrigerant delivery stops.

A sharp decrease in pressure in the tube 5 of the sensor 5, i.e. high speed pneumatic valve 4. due to the high thermal conductivity of zeolites and their ability to operate in a vacuum pump. In addition, the high speed of the pneumatic valve is due to the fact that the layer of capillary-porous material 11 does not prevent the sensor from cooling when immersed in a liquid. The fact is that, due to the porosity of the material, the liquid flows freely to

5 sensor 5 and cools it. Moreover, due to capillary forces, the liquid rises over the coating, as a result of which not only that part of the sensor that is immersed in the liquid, but that is also cooled. which is above the liquid level.

Thus, a layer of capillary-porous material reliably protects the sensor from cooling it with vapors of a cryogenic liquid, at the same time this layer does not prevent the sensor from cooling at all when immersed in liquid and even intensifies this cooling. This eliminates the step load of the consumer and reduces the charge time, which improves the performance of the device.

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Claims (1)

Invention Formula Device for automatic dispensing of liquid refrigerant St. No. 1214983, characterized in that, in order to increase productivity 5, the sensor is provided with an outer coating in the form of a capillary-porous layer.