RU2213003C1 - Plant of continuous electric heating and mixing of concrete mix - Google Patents

Abstract

FIELD: construction engineering, particularly, preparation of concrete mixes. SUBSTANCE: plant includes receiving bin, body, multistart screw having shaft and pins located along helical line, and electrodes. Screw is made of electrical insulating material, and body and screw pins are made of current conducting material. Pins are mounted on screw shaft with gap from body not exceeding size of fine filler. Each electrode is located on screw shaft along helical line with spacing equaling screw pitch. Distance between electrode and pins equals distance between body and electrode. EFFECT: increased intensity of mixing and heating of mix due to higher wear resistance with simplified design of plant and increased its service life. 2 dwg

Description

 The invention relates to the field of construction, namely to the preparation of concrete and the like mixtures.

 Known continuous installations for electrical heating of concrete mixture, containing a receiving hopper, a housing mounted under it with a single-screw screw screw for mixing and transportation, and insulated electrodes placed on the inner surface of the housing / 1, 2 /.

 The disadvantages of such devices is that the auger is laborious to manufacture and has a short service life due to significant wear of the auger. In addition, such devices provide the movement of the mixture without sufficient mixing during its heating, which reduces the quality of the mixture by the uniformity of the heating temperature and composition.

 The closest technical solution to the claimed is a continuous installation for electrical heating and mixing of concrete mixture containing a receiving hopper, a housing, a screw with fingers and electrodes mounted on the inner surface of the housing / 3 /.

 The disadvantage of the installation is that the screw is made of fingers insulated from the electrodes, which leads to rapid wear of the screw and insufficient intensity of heating the mixture.

 The technical problem is to increase the intensity of mixing and heating the mixture by increasing wear resistance while simplifying the design and increasing the service life.

 The problem is solved in such a way that in a continuous installation for electric heating and mixing of concrete mixture, including a receiving hopper, a housing, a multi-feed screw, consisting of a shaft and fingers located along a helical line, and electrodes, according to the invention, the screw is made of electrical insulation material, and the housing and fingers of the screw are made of conductive material, while the fingers are mounted on the shaft of the screw with a gap from the body of not more than the size of a small aggregate, and each electrode is placed on the shaft of the screw, the distance between the electrode and the fingers is equal to the distance between the body and the electrode.

 The proposed design differs from the known one in that the screw shaft is made of electrically insulating material, and the housing and fingers of the screw are made of conductive material, while the fingers are mounted on the screw shaft with a gap of no more than fine aggregate from the housing, and each electrode is placed on the screw shaft by helix with a step equal to the pitch of the screw, and the distance between the electrode and the fingers is equal to the distance between the housing and the electrode.

 When passing the concrete mixture along the housing in the area of the electrodes, the electrodes and fingers and the electrodes and the housing are closed through the concrete mixture. As a result of the passage of a uniform electric current throughout the volume through the concrete mixture, the intensity and uniformity of its heating increase. There is no voltage on the case due to the uniform distribution of phases, which increases electrical safety.

 In addition, the housing design is simplified by eliminating the insulating elements, and the wear resistance of the parts and the durability of the installation are also increased.

 In FIG. 1 shows the installation (longitudinal section), figure 2 - section aa of figure 1.

 The device consists of a frame 1, a receiving hopper 2, a housing 3, a shaft 4 and fingers 5 of a multi-auger screw, electrodes 6, an electric drive 7. Moreover, the fingers 5 of the screw, to prevent them from jamming with aggregate particles, are made with a gap from the surface of the housing of no more than small placeholder. Each electrode 6 is placed along a helix with a step equal to the pitch of the screw, and the distance between the electrode and the fingers L is equal to the distance between the housing and the electrode.

 Installation works as follows.

 Concrete mixture through the receiving hopper 2 is continuously fed into the housing 3 mounted on the frame 1. Using a screw, consisting of a shaft 4, made in the form of a pipe of insulating material and metal fingers 5, the mixture is moved along the housing 3 with simultaneous stirring and heating using electrodes 6 and is discharged into the dispensing container.

 When passing the concrete mixture along the body in the area of the electrodes, the electrodes, fingers of adjacent turns and the body short-circuit through the concrete mixture. As a result of the passage of a uniform electric current throughout the volume through the concrete mixture, the intensity and uniformity of its heating increase.

 The proposed installation allows to increase the uniformity of the heated mixture due to its mixing during heating and movement, as well as to simplify the design and increase the service life.

Sources of information
1. SU Copyright certificate 1678629, cl. B 28 B 17/02, 1991

 2. SU Copyright Certificate 343966, cl. B 28 B 17/02, 1972

 3. RF patent 2080990, cl. B 28 B 17/02, BI 16, 06/10/97 / prototype /.

Claims (1)

 A continuous installation for electrical heating and mixing of concrete mixture, including a receiving hopper, a housing, a multi-feed screw, consisting of a shaft and fingers located along a helical line, and electrodes, characterized in that the screw shaft is made of electrical insulation material, and the housing and fingers of the screw are of conductive material, while the fingers are mounted on the screw shaft with a gap of no more than a small aggregate from the housing, and each electrode is placed on the screw shaft along a helical line with a step equal to the screw pitch, with p Normal distance between the electrode fingers and equal to the distance between the housing and the electrode.

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