SU100519A1 - Method for automatic detection and control of moisture content of ceramic mass - Google Patents

Description

In the production technology of ceramic products, compliance with the molding moisture of the ceramic mass is one of the most important conditions for ensuring the stable quality of these products.

At present, in ceramics factories, the mass moisture control is carried out by drying the sample taken to a constant weight. Such control is imperfect, as. it allows only to fix the molding moisture, and only about 2-3 hours will know about its deviation from the required value.

The moisture control of the mass will be effective only if it allows for timely measures to be taken when the moisture content deviates from the desired one. The control method should be especially effective, allowing us to provide automatic regulation of humidity.

To automatically control and regulate the moisture content of the mass for ceramic products (both in plastic and semi-dry methods of their production), it is proposed to use as a criterion the magnitude of the pressing force or the power consumed by the press at a constant thickness and height of the mass poured into the mold.

A diagram of the device for controlling the humidity of the ceramic material is shown in the drawing.

To regulate the moisture of the ceramic mass, the scale of the pressure gauge or wattmeter recording the pressing force or power consumed by the press is provided with an electrocontact plate I located from the zero division to the point corresponding to the moisture of the molding material, which interacts with the contact on the working arrow 2 of the device.

Plate / and the contact arrow 2 are attached to the circuit of the step-down transformer 3.

When the circuit is closed by the contact plate and the contact of the arrow 2 through the time relay 4 and the intermediate relay 5, the actuator 6 is switched on to be humidified.

If the pressure corresponding to the molding moisture is exceeded, arrow 2 of the device will go beyond the contact plate, the circuit

open, the actuator shuts off and opens the steam passage or water for humidification. When the gauge needle returns to zero, the spova circuit closes.

In order to prevent the impulse from being transmitted to the actuator 6 during the period of return of the arrow BI, the zero position is established by a time relay, which ensures the circuit to close only after a certain time, a little longer than the return time of the arrow to its initial position and moving it to the position of maximum deviation.

Thus, over the entire period when the set pressure is exceeded, the actuator will be turned off, which will ensure a constant passage of water or steam for humidification.

With a press pressure lower than the established one (the humidity of the press powder is higher than the required one), the contact of the arrow and the contact plate are permanently closed (both when the constant pressure is reached and when it drops to zero), which ensures the activation of the actuator blocking the passage of steam or water.

For more precise adjustment of the vacuuming, additional contact plates 7 and 5 can be installed, which will be closed by the corresponding contacts of the working arrow n and transmit the pulses to the actuators in the manner described above. In this case, the contact plate / will extend from the zero division to the point corresponding to the minimum permissible limit of humidity, and the contact plate 8 from zero division to the point corresponding to the maximum permissible limit of humidity, and the contact plate 7 from zero division to the point corresponding to moisture intermediate between maximum and minimum permissible.

In this case, the operation of the auto device will be reduced to the following. When the pressure increases, which corresponds to the minimum allowable humidity limit, the instrument's working arrow will go beyond all three contact plates, the circuit of all actuating mechanisms will open and they will open the steam and water passage for humidification.

With a slight decrease in pressure, the contact plate closes}, the corresponding actuator will turn on, which will stop the wetting. When the pressure corresponding to the closure of the contact plate 7 is reached, the humidification will stop using the following actuator. When reaching the pressure corresponding to the closure of contact 8 (maximum permissible limit of humidity), the humidification will be completely stopped.

Taking into account the presence of a certain relationship (with a constant filling height and thickness of raw material) between humidity and press pressure, as well as power consumption, the corresponding devices (pressure gauge, wattmeter) can be calibrated directly in moisture values. Last, along with automatic humidity control, it will also provide a quick determination of its value.

During plastic molding, pressing occurs continuously, therefore, the readings of the instrument will consistently correspond to the consumed power (without returning the arrow to the zero position). This simplifies the circuitry by eliminating the time relay.

Subject invention

Claims (2)

1. A method for automatically determining and controlling the moisture of a ceramic mass when pressing it, characterized in that, in order to automatically determine and control the moisture of the mass when pressing directly into the products, the thickness and height of the mass in the form are kept constant for a given weight of products, and the degree of moisture of the mass they are determined by the magnitude of the pressing force or, respectively, by the power consumed by the press. 2. To implement the method according to claim 1, use a contact pressure gauge that measures the pressing force, or a contact wattmeter that measures the power consumed by the press, the contact plates of which are parallel to the slider and the moving contact is fixed on the indicator arrow of this device that automatically supplies current pulses mass wetting mechanism.