SU1344702A1 - Jet-type feeder for pneumatic transportation of loose material through pipeline - Google Patents

Abstract

The invention relates to the field of pneumatic conveying of bulk materials through pipelines. The purpose of the invention is to reduce energy consumption. The jet feeder contains a hollow cylindrical body 1 with an inlet 2 and an outlet 3 parts, a loading chamber 8 and a transport pipeline 5. In the inlet part 2, a Laval nozzle 11 is mounted, which communicates with a source of compressed air. The nozzle 11 has the possibility of axial movement. Holes 13 are provided in the inlet part 2. At the inlet part 2, a perforated ring 14 is rotatably mounted, the perforations 15 of which can be aligned with the apertures 13 to communicate the inlet part 2 with the atmosphere. The inlet part 2 in the zone of the outlet part of the nozzle 11 is made with a confuser 12. In the outlet part 3 an additional Laval nozzle 16 is mounted with the possibility of axial movement. Between the additional nozzle 16 and the inlet part 2, an annular hollow elastic element is mounted, communicating through the duct with the loading chamber 8. With respect to the outlet part, the additional nozzle 16 is spring-loaded by means of springs. Ink feeder works as follows. Through the nozzle 11, compressed air is supplied to the housing 1. The air flow ejects atmospheric air through the holes 15 and 13. The amount of ejected compressed air is controlled by turning the ring 14 and aligning the holes 13 and 15. The ejected air through the holes 15 and 13 is displaced with the stream of compressed air and, passing through the additional nozzle (L with N 4 О 1ЧЭ

Description

The shaft 16 is further accelerated. A jet of compressed air at high speed, the exit from the additional nozzle 16, carries away

The invention relates to pneumatic transport, in particular to jet feeders for a system for the pneumatic transport of bulk materials through pipelines, and can be used in devices for the pneumatic transportation of bulk materials in the mining industry, in the construction industry and other industries.

The purpose of the invention is to reduce the energy intensity of the feeder.

FIG. 1 shows a jet feeder, a general view; in fig. 2 — node I in FIG. 1. The jet feeder consists of a hollow cylindrical body 1 with an input 2 and an output 3 parts, between which the mixing section 4 is located, having a length of at least 8-12 diameters. The outlet part 3 is coaxially collapsed with the transport pipeline 5 through the accelerating part 6 and the diffuser 7. At an angle, the output part 3 communicates with the loading chamber 8, to which the feeder 9 is attached to the bulk material. A guide bushing 10 is mounted in the inlet part 2 of the housing 1, in which the Laval nozzle 11 is connected coaxially to the housing 1 with an annular gap relative to it with axial movement. The inlet part 2 of the housing 1 in the area of the outlet part of the nozzle 11 is made with a confuser 12. In the inlet part 2 there are through holes 13. At the inlet part 2 a perforated ring 14 with perforations 15 is mounted. wherein the perforation of the ring 15 is aligned with the openings 13 of the inlet part 2 to communicate the inlet part 2 with the atmosphere. In the output part 3, an additional Lawal 16 nozzle is mounted coaxially with the body, with an annular gap relative to the body. Additional nozzle 16 is mounted for axial movement. The device for moving the additional nozzle 16 may be made in the form of a hollow annular elastic element 17 placed between the flange 18 of the additional nozzle 16 and the flange 19 of the mixing section 4 or the flan

particles of bulk material from the loading chamber 8 into the transport pipeline 5. 2 Cp. f-ly, 1 ill.

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5 5 5

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The inlet part of the body 2 is cement. On the other hand, the flange 18 of the additional nozzle is spring-loaded with spring 20 relative to the outlet part 3 of the body. The cavity of the hollow annular elastic element 17 is communicated by the duct 21 with the cavity of the loading chamber 8.

Ink feeder works as follows.

The flow of the ejecting compressed air from the blower installation enters the nozzle 11, in which it is converted in such a way that at the nozzle exit the speed of the outflow of the air flow is greater than the speed of sound and the static pressure is below the total atmospheric pressure. Under the action of this pressure difference, air from the surrounding atmosphere, through the perforations 16 of the ring 14 and the openings 13 of the inlet part 2, enters the annular gap between the nozzle and the body, and then into the mixing section 4. In the initial section of the mixing section 4, particles ejected from the surrounding Atmospheres of air are continuously captured by high-speed ejecting air streams flowing from nozzle 11 and entrained by it into the mixing section. Due to this, a vacuum is maintained at the inlet to the mixing section 4, which ensures the flow of air from the surrounding atmosphere into the confuser 12. In the mixing section, the ejecting and ejected air flows move and equalize the velocity field before entering the outlet part 3. Uniform sex velocity in cross section the mixing section before entering the exit part 3 is necessary to ensure high efficiency of the additional Laval nozzle 16. In the additional nozzle 1 Laval 16 an hour occurs Alternate speed recovery and static pressure reduction of the complete (ejecting and ejectable) air flow slowed down in the mixing section, which makes it possible to introduce the bulk material into the transport pipeline 5. The bulk material with a certain initial velocity is fed through the feeder 2 into the loading chamber 8 and then into the booster section 6, where it is aerated by the air flow coming from the additional Laval nozzle 16 and entrained by this flow through the diffuser 7 to the transport line 5. In the loading chamber 4, the boost portion 6 and the diffuser 7 airflow velocity head part is changed to almost static mode, it is necessary to provide a stable conveying of bulk material in the transport pipe 5. The upper portion 6 is designed to equalize the flow to the diffuser 7.

The entry of atmospheric air into the inlet part 2 through the apertures 13 of the inlet part 2 and the apertures 16 of the ring 14 is controlled by rotating the ring 14 around the inlet part 2 and moving the nozzle 11.

If the holes 13 and 16 are completely aligned, then the flow of air from the atmosphere as much as possible, and if the holes completely overlap, then there is no flow of air at all.

When the nozzle 11 is moved relative to the guide sleeve 10 towards the blower unit, the area of the annular gap between the nozzle and the housing increases, and when the nozzle moves And towards the output part 3, the area of the annular gap decreases, and thus the air ejected from the atmosphere is adjusted.

The axial movement of the additional Laval nozzle 16 makes it possible to establish such a position of the nozzle 16, at which it is possible to completely eliminate knocking out of small particles and bulk dust from the loading chamber 8 back to the feeder 9. The additional Laval nozzle 16 is installed in the required position when the gas flow former is assembled depending on the type of material transported and may also be carried out during the operation of the jet feed, for example, with varying air flow patterns or kinds of transported bulk material (by physicomechanical properties) leading to the material being knocked out of the loading chamber 8 into the material feeder 9. The movement of the additional Laval nozzle 16 during the operation of the former is, for example, as follows.

When increasing the pressure in the loading chamber 8, caused by knocking the material out of the loading chamber 8 into the feeder 9, the tube 17 is pressurized through the tube 2, which acts on the flange 18 of the additional Laval nozzle 16, moves it towards the loading chamber 8. the springs 20 are compressed. The additional nozzle Laval 16 moves until the forces of the element 17 and the springs 20 equalize. With a decrease in pressure in the loading chamber 8

element 17 is blown out through the tube 21 into the loading chamber 8 and moving under the action of the nozzle springs 20 relative to the loading chamber 8 towards the mixing section 4. The additional Laval nozzle 16 can be moved by any other known method.

Installing a nozzle 11 with an annular gap with respect to the inlet part 2 allows atmospheric air to be ejected through apertures 13 and 16 evenly spaced on the side surface of the inlet part 2, and excludes the possibility of dislodging compressed air through the said holes 5 when the nozzle 11 is moved.

Evenly spaced holes 13 and 16 on the side surface of the inlet part 2 and the implementation of the inlet part 2 with confuser 12 allow the ejected atmospheric air to be evenly distributed, and the implementation of the mixing section 4 with a length of at least 8–12 of its diameter allows air to be introduced into the outlet part 3 flow with equalized velocity profile and neither.

five

The implementation of the additional nozzles 11 and 16 in the form of Laval nozzles allows to increase the speed of the ejecting compressed air.

Claims (3)

1. Jet feed for pneumatic conveying of bulk material through a pipeline, comprising a hollow cylindrical body with inlet and outlet parts, the last of which is coaxially 5 communicates with the transport pipeline, and at an angle with the loading chamber, a nozzle for supplying compressed air to the housing mounted in the inlet part coaxially with the housing and with an annular gap relative to it with the ability to move along  the housing axis, and a device for communicating the entrance part of the case with the atmosphere, characterized in that, in order to reduce energy intensity, it is equipped with an additional nozzle mounted in the outlet part 5 coaxially with the body in the zone of communication with the loading chamber and with an annular gap relative to the body can be moved along its axis, while the entrance part of the body in the nozzle area is made with a confuser, and both nozzles are made in the form of Laval nozzles. 2. Citate. 1. according to claim 1, characterized in that in the entrance part of the housing: through holes, and the device for communicating the inlet of the housing with the atmosphere is made in the form of a perforated ring mounted on the inlet of the housing for rotation with respect to it and aligning the perforation of the ring with the apertures of the housing. 3. A feeder according to claim 1, characterized in that it is provided with a hollow annular elastic element placed between the additional nozzle and the inlet part of the housing and communicated with the cavity of the loading chamber, wherein the additional nozzle is spring-loaded relative to the outlet part of the housing. 20 fie.2