RU2207247C1 - Press-roll extruder - Google Patents

Abstract

FIELD: chemical industry, manufacture of building materials, agricultural production; applicable in granulation of various powdery materials, particularly, combined fodders. SUBSTANCE: press-roll extruder has body with loading bin located on body external surface, device for heating of pressed mass and knife for granule cutting. Body accommodates auger, die, and pressing rolls installed on immovable eccentric axles secured to body. Extruder is provided with conical nozzle made in form of two conical sleeves located in each other with formation of channel narrowing towards die. Nozzle is installed at auger outlet so that external sleeve is rigidly connected to body wall, and internal sleeve is rigidly secured to shaft. Pressing rolls are made with eccentricity and with flexible working surfaces. Die is installed on auger shaft behind conical nozzle. EFFECT: higher density of granules of pressed material, reduced overall dimensions of extruder. 5 cl, 3 dwg

Description

 The invention relates to various industries: chemical, building materials industry, agricultural production and can be used for granulation of various powder materials, in particular feed.

 Known extruder for the preparation of granules, containing a cylinder equipped with a loading funnel and a discharge opening, a screw rotating inside it, consisting of separate axle boxes, between which steam lock washers are installed, moisture control devices are installed on the upper part of the cylinder behind the steam lock washers, in the cavities of which there are coils connected with a refrigerant supply system, and a condensate tray (see USSR AS 1646536, 1991) - analogue. The disadvantages of the known solutions are both low productivity and the complexity of the design.

 The closest solution in terms of technical nature and the achieved effect is a press-roll extruder containing a housing, on the outer surface of which there is a loading hopper and a device for heating the pressed mass, and inside there are a screw, a matrix and on stationary eccentric axes mounted on the housing - pressing rolls (see the book "Presses of food and feed production" edited by A.Ya. Sokolov, M., Mechanical Engineering, 1973, p. 266, Fig. 149) - prototype.

 The disadvantages of this solution are the low density of the granules (they are densified by a screw and rollers), large dimensions (screw and die are installed on different shafts), low operating conditions of the entire unit due to increased wear on the pressing surface of the working bodies, including the complexity of dismantling the matrix and the inability to heat the material inside the case for the operation of the press at any time of the year.

 The objective of the invention is to increase the density of granules of the pressed material, reduce the overall dimensions of the device, including improving the operating conditions of the unit by increasing the overhaul period, as well as providing the possibility of operation of the unit at any time of the year.

 To achieve this goal, a well-known press-roll extruder containing a housing, on the outer surface of which there is a loading hopper, a device for heating the pressed mass, a knife for cutting granules, and a screw, die and fixed eccentric axes mounted on the housing are installed inside - pressing rolls equipped with a conical nozzle made in the form of two cone-shaped bushings located one in the other with the formation of a tapering channel in the direction of the matrix, and installed at the exit of the screw in this way the outer sleeve is rigidly secured to the housing wall, and also inner tough - the shaft. In this case, the press rolls are made with eccentricity and elastic working surfaces, and the matrix is mounted on the screw shaft behind the conical nozzle.

 The device for heating the pressed mass can be made in the form of an envelope without a gap, the screw part of the bandage housing, consisting of type-setting insulating elements, inside of which there are heaters.

 The matrix can be made of removable arched elements rigidly fixed to each other.

 The fixed eccentric axes of the press rolls can be equipped with high frequency vibrators.

 The eccentricity of the press rolls can be no more than 0.05 D, where D is the diameter of the press roll.

 The implementation of the conical nozzle of the proposed design provides additional compaction of the pressed mass and the removal of the gaseous phase from it.

 The implementation of the press rolls with an eccentricity and elastic working surfaces ensures constant contact of the press rolls with the die and exposure of the pressed material under pressure, which reduces the elastic deformation of the compressed granules and improves their quality (eliminates the formation of re-cracking cracks and chips).

 The installation of the matrix on the screw shaft behind the conical nozzle can significantly reduce the overall dimensions of the device, improve the quality of the compressed granules and increase the productivity of the unit.

 The implementation of the device for heating the pressed mass in the form of an envelope without a gap, the screw part of the bandage housing, consisting of type-setting insulating elements inside which the heaters are located, allows the unit to be operated at any time of the year by heating the material in the winter.

 The manufacture of a matrix of removable arcuate elements fixed to each other simplifies its manufacture (cumbersome equipment is not used) and operating conditions, the overhaul period increases since during matrix repair, it is possible to replace individual worn removable arched elements, and not the entire matrix.

 The supply of stationary eccentric axes of the pressing rolls with high-frequency vibrators allows to intensify the molding process of the pressed mass and to reduce the resistance when pressing granules, without reducing their density.

 The implementation of the press rolls with an eccentricity not exceeding 0.05 D, where D is the diameter of the press roll, can further improve the quality of the molding by creating a short-term pulsed load and better conditions for gripping the material. If the eccentricity is greater than 0.05 D, it is possible to increase the resistance during rotation of the press rolls and worsen the conditions for forcing the pressed material through the holes of the matrix.

 Comparative analysis with the prototype shows that the press-roll extruder is equipped with a conical nozzle made in the form of two cone-shaped bushings located one in the other with the formation of a tapering channel in the direction of the matrix, and installed at the exit of the screw in such a way that the outer sleeve is rigidly fixed to the wall cases, and the inner one is also rigidly mounted on the shaft, the pressing rolls are made with eccentricity and elastic working surfaces, while the matrix is mounted on the screw shaft behind the conical nozzle, therefore, The claimed solution meets the criterion of "novelty."

 Signs that distinguish the claimed solution from the prototype, the study of patent technical literature has not been identified, which allows us to conclude that the proposed solution meets the criterion of "inventive step".

 The proposed press roll extruder is shown in the diagram.

In FIG. 1 shows a General view, figure 2 is a section aa in figure 1, figure 3 is a section bb in figure 2. The device comprises a housing 1, on the outer surface of which there is a loading hopper 2 and a heating device 3, made, for example, in the form of a supply fitting with a valve, and to achieve a more complete heating of the pressed mass inside the housing at any time of the year, the heating device can be made in form, envelope without a gap, the screw part of the body of the bandage, consisting of type-setting insulating elements 4, inside of which there are heaters. Inside the housing 1, a matrix 6 is mounted on the shaft of the screw 5, made, for example, in the form of a shell, and to improve operating conditions, the matrix 6 can be made of removable arc-shaped elements 7, fixed to each other, for example by bolt connections. On the stationary eccentric axes 8, press rolls 9 are installed, made with an elastic working surface 10, which are mounted eccentrically. It is desirable that the eccentricity does not exceed 0.05 D, where D is the diameter of the roll. The press roll extruder is equipped with a conical nozzle made in the form of two cone-shaped bushings 11 and 12, arranged one in the other with the formation of a tapering channel 13 towards the matrix 6. It has been experimentally established that the most optimal cone-forming angles are 11-17 ^o . The outer sleeve 11 is rigidly mounted, for example by welding, on the wall of the housing 1, and the inner 12 is also rigidly mounted, for example by welding, on the shaft. To cut off the finished granules, a knife is installed on the wall of the casing 1. The fixed eccentric axes 8 of the press rolls 9 can be equipped with high-frequency vibrators 15 installed, for example, cantilever. The presence of vibrators further increases the mobility of the mass, which leads to an improvement in the forcing of the pressed mass through the holes of the matrix.

 The inventive device operates as follows. The powder material prepared for molding is fed through the hopper 2 into the inside of the housing 1 onto the rotating screw 5. The screw 5 mixes the pressed mass and transports it to the zone of the tapering channel. By heating device 3, the pressed mass is heated to the temperature of vaporization, which increases the plastic properties of the material and the density of the formed granules. The pressed mass with the required temperature by the screw 5 is pressed through the tapering channel 13 formed by the cone-shaped bushings 11 and 12. When the pressed mass is moving along the tapering channel 13, it is hardened and fed into the interior of the die 6. The die 6 rotates the eccentrically mounted pressing rollers 9 pressed against it. with an elastic working surface, which capture the pressed mass and push it through the hole of the die 6. The elastic surface of the rolls provides a reliable grip of the material, and constant first rollers contact with the matrix through the compressible mass, and this increases the turnaround time of the pressing organs. The combined effect of the elastic surface and the eccentricity of the rolls increases the mobility of the mass and further compacts it when punching through the holes of the matrix. Vibrational impact on the press rolls reduces the resistance to forcing the mass through the holes and improves the quality of the granules. The matrix can be made of removable elements that are fastened to each other, for example by bolts, which allows, in case of wear of a part of the matrix, to replace the worn part without dismantling the entire matrix. If the heating device is made in the form of an envelope without a gap, the screw part of the bandage housing, consisting of a set of insulating elements made of, for example, ceramic, inside of which there are heaters, such as shades, spirals, etc., this allows a better heating of the entire pressed mass in the unit itself at any time, especially in winter. The obtained granules are cut with a knife 14 and fed into the processing line for their further processing. After which the cycle repeats.

 Prepressing the molding material with the screw 5 in the tapering channel 13, as well as the final forcing of the material through the holes of the matrix 6 allows to obtain granules of higher density and better quality.

 Thus, the proposed solution provides an increase in the density of granules with an improvement in their quality, a decrease in the overall dimensions of the device, including simplification of the manufacture of a matrix consisting of removable elements, and an improvement in the operating conditions of the unit by increasing the overhaul period, as well as the possibility of operating the unit at any time years due to the heating of the material in the winter.

Claims (5)

 1. A press-roll extruder comprising a housing, on the outer surface of which there is a loading hopper and a device for heating the pressed mass, a knife for cutting granules, and a screw, a die are installed inside and on stationary eccentric axes mounted on the housing, the press rolls, characterized in that the extruder is equipped with a conical nozzle made in the form of two cone-shaped bushings located one in the other with the formation of a tapering channel in the direction of the matrix, and installed at the exit of the screw in such a way that the external w LCA is rigidly attached to the housing wall, and also inner rigid - on the shaft, wherein the roller presses are made eccentrically and elastic working surfaces and the matrix mounted on the shaft of the conical screw head.  2. The press-roll extruder according to claim 1, characterized in that the device for heating the pressed mass is made in the form of an envelope without a gap enveloping the screw part of the body of the bandage, consisting of type-setting insulating elements, inside of which there are heaters.  3. Press roller extruder according to claim 1, characterized in that the matrix is made of removable arcuate elements fixed to each other.  4. Press roller extruder according to claim 1, characterized in that the stationary eccentric axis of the press rolls are equipped with high-frequency vibrators.  5. The press roll extruder according to claim 1, characterized in that the eccentricity of the press rolls is not more than 0.05 D, where D is the diameter of the press roll.

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