WO2024251329A1 - Mould body and method for monitoring the mould body - Google Patents

Abstract

The invention relates to a mould body (1) comprising a sensor box (3) having the following features: a. The sensor box (3) has a length sensor system (18) for measuring a thickness of the mould body (1), wherein the length sensor system (18) has a plurality of conductor tracks arranged at a distance from one another in the thickness direction, wherein the sensor box (3) uses the number of conductor tracks present to determine a measured value which correlates with the thickness of the mould body (1), b. The sensor box (3) has an NFC antenna (10); c. The sensor box (3) has a control unit (9) and a battery (8); d. The control unit (9) has a processor, a flash memory, a RAM memory, at least one further sensor and a second antenna.

Description

Mould body and method for monitoring the mould body

The invention relates to a mold body and a method for monitoring the mold body

During use, the mold bodies of continuous casting molds are subject to wear, which leads to changes in the surface of the casting side. The casting sides are reconditioned by the operator. Reconditioning is carried out by removing material. The process can be repeated several times. The usage data and the rework status are recorded for this purpose.

Casting process data, e.g. the duration of use, are usually only linked manually with mold data, such as the plate thickness or the rework status. Process data on the rework status of the mold are usually recorded and documented manually. Regarding the state of the art, reference is made to DE 100 28 304 A1, which discloses a method for processing casting data in a continuous casting mold. It is proposed to arrange cooled field bus modules directly on the continuous casting mold and to feed data to a control system of the continuous casting plant via a bus line.

EP 3 831 510 A1 discloses that a sleeve can be arranged in a recess on a mold wall of a continuous casting plant, in which an RFID transponder is fixed by means of adhesive in order to implement usage tracking.

US 2013 / 0 333 473 A1 describes a real-time monitoring method for mold plates in which the data is transmitted wirelessly.

The invention is based on the object of demonstrating a mold body and a method for monitoring it, whereby the casting process data can be recorded more easily in order to be able to use them better for rework.

To solve this problem, a mold body according to patent claim 1 and a method for monitoring the mold body according to patent claim 7 are proposed.

The mold body according to the invention has at least one sensor box with the following features: The sensor box has a length sensor for measuring a thickness of the mold body, wherein the length sensor has several conductor tracks arranged at a distance from one another in the thickness direction of the mold body, wherein the sensor box determines a measured value based on the number of conductor tracks present, which correlates with the thickness of the mold body. In addition, the sensor box has an NFC antenna, a battery and a control unit. The control unit has a processor, a flash memory, a RAM memory, at least one further sensor and a second antenna. The NFC antenna is equipped for near-field communication. It serves to wake up the sensor system of the sensor box using an external signal and to enable subsequent data transfer for reading the sensor box. The battery ensures a power supply. The entire sensor system, in particular the components of the control unit, is preferably optimized to ensure a service life of more than 5 years without replacing the battery or the sensor box of the mold plate.

The flash memory is a digital memory component for non-volatile storage without maintenance energy consumption. It is also known as a flash EEPROM. In particular, a unique identifier (ID of the mold body) is stored in the flash memory.

The control unit also contains at least one further sensor. A sensor of the at least one further sensor is used to record oscillations of the mold body. The control unit contains a second antenna. The second antenna is preferably a Bluetooth Low Energy antenna (BLE). This standard is specially designed for sensors in order to transmit wireless data that is as energy efficient as possible. The data is read out without contact.

With the mold body according to the invention and the at least one sensor box arranged on it, casting process data can be recorded, such as the operating time and the oscillation as well as mold process data, e.g. the plate thickness. The sensor box automatically records the mold process data. The mold data also includes the maintenance history, which can be documented. By using several sensor boxes, i.e. by recording the oscillation at several points on a mold, it is possible to detect wobbling movements of the mold body. Wobbling movements can cause both increased wear of the mold and product defects or, in extreme cases, a strand break.

With regard to the rework status of the mold plate, it is considered particularly advantageous that the sensor box is connected to a length sensor for measuring the thickness of the mold body. The length sensor has several conductor tracks arranged at a distance from one another in the direction of thickness. The conductor tracks have a fixed distance. The distance between the conductor tracks is, for example, 0.05 or 0.2 millimeters and defines a measuring increment. If the mold plates show signs of wear, they are reworked. During the process, the mold plate is milled off. Due to the positioning The number of conductor tracks is reduced or individual conductor tracks are interrupted by the length sensor or the individual conductor tracks. The sensor box or the sensors arranged in it determine the number of existing or intact conductor tracks over a measuring range, which assumes a specific measured value due to the incremental arrangement, which in turn correlates with the thickness of the mold body. In this way, the rework status of the mold plate can be recorded automatically.

The sensor box has a housing and a lid so that the sensors are protected. The sensor box is detachably connected to the mold body. In particular, the sensor box is screwed to the mold body. Housing the sensors in a housing with a lid has the advantage that the sensor box can be removed during the rework step. The sensor box is preferably made of plastic, in particular Teflon, to enable the sensors to be read using NFC and the second antenna.

The sensor box is preferably placed very securely on the mold body. In particular, the mold body is a mold plate that has a narrow front side into which the sensor box is inserted. The sensor box has a base body that is arranged at a distance from a casting side of the mold plate. The base body in particular has a flange that protrudes towards the casting side. The length sensor for measuring the thickness of the mold plate is preferably arranged at least partially on this flange that protrudes towards the casting side. The sensor box is preferably attached in the upper area of a front side of a mold plate. The term "top" refers to the installation position, with "top" referring to the pouring end of the mold.

Overheating of the sensors is prevented in this position. There is no contact between the base body and the liquid melt. Furthermore, the sensors can be positioned here so that the length sensors have direct contact with the hot side/casting surface of the mold plate to be processed.

A method for monitoring the mold body is described in claim 7, according to which the at least one further sensor detects an oscillation of the mold body during casting, wherein the time of the oscillation is stored. If an acceleration, i.e. an oscillation, is detected, a measurement is carried out over a few seconds, for example over 5 to 15 seconds, especially 10 seconds. Using logic adapted to continuous casting, the control unit can automatically detect whether a casting process is taking place.

The frequency range of the oscillation of the mold body is preferably between 1 Hz and 10 Hz. In addition, a sinusoidal movement must be present. The sinusoidal movement is detected by an FFT analysis.

If these conditions are met, the control unit records the start time of the acceleration event. A control measurement is automatically performed after a set interval, for example after 5 to 30 minutes. This measurement is compared with the previous measurement. If the measurement has similar parameters, e.g. a similar frequency range, the onset time and the center frequency in Hz are recorded for this measurement period. The onset time and the oscillation are recorded as long as the oscillation or acceleration event, i.e. the pouring sequence, lasts. All data is preferably encrypted.

An interface can be used to identify the mold body and establish a connection with the sensors, which transfer the sensor data to a reading unit and from there to an evaluation unit. This can be a mobile handheld device, in particular a smartphone. Modern smartphones have the necessary antennas and interfaces. The evaluation is carried out using an app on the smartphone or software on a mobile handheld device specially provided for this purpose. The evaluation unit can transfer the data to a server-side database that can be accessed by manufacturers and/or customers via certain interfaces. In particular, all sensors can only be read using a digital key that can be checked on the smartphone or the reading unit.

Before installing the sensor in the mold body, it is essential that it is described with the mold body ID as a unique identification. The app on the smartphone or reading unit is then used to calculate the Total time, i.e. the sum of all individual sequences of use of the mold body. The app displays the process data sequence by sequence. The read-out data can be supplemented with photos and texts that are generated directly on the smartphone, which is helpful for documenting maintenance. With the help of the app, the data obtained in this way can be synchronized with a server-based database. In addition to the casting process data, the database can also contain other information, such as customer information, master data, product name, material, material batch number, order date, production date, coating, taper, drawing number and weight. In addition, documents such as dimension records, drawings, etc. can be included in the database. The database can also be accessed via a customer portal. The customer portal can display automated statistics on temperature loads and usage times, which can be used to determine the performance of the mold plates.

In particular, the use of several sensors in a mold body makes it possible to determine harmful wobbling movements of the mold body.

Initially, a mold body can be provided with a unique identification, such as a QR code. The QR code can be read by a camera on the smartphone, which correlates with the mold body ID that is stored in the sensor box. If this data is linked, the QR code is superfluous. All casting data and status data of the mold can then be automatically assigned via the smartphone.

With the mold body according to the invention or the method according to the invention for monitoring the mold body, it is no longer necessary to manually link casting process data with mold data, in particular the plate thickness. Process data on the rework status of the mold no longer have to be manually recorded and documented. The performance of the mold can be automatically evaluated. In addition, wobbling movements can be detected on the mold side in order to draw conclusions about increased wear of the mold. The invention is explained in more detail below using an embodiment shown in the drawings. They show:

Figure 1 is a perspective view of a mould body with an enlargement of a detail in its upper corner area;

Figure 2 shows a sensor box inserted into the mold body of Figure 1;

Figure 3 shows the sensor box of Figure 2 in a first side view;

Figure 4 shows the sensor box of Figure 2 in a view of its lid and

Figure 5 shows the overall system for monitoring the mold body.

Figure 1 shows a mold body 1 in the form of a mold plate with a view of its casting side 19. In the upper corner area of the mold body 1, on one end face 2, there is a sensor box 3, which is shown somewhat larger in the detailed illustration. Figure 2 shows the sensor box 3 with further details. The sensor box 3 has approximately the shape of a mortise lock for a door, i.e. its housing 4 has a narrow cuboid-shaped base body 15, on one end of which fastening tabs 16, 17 are arranged at opposite upper and lower ends, which protrude beyond the cuboid-shaped base body 15. The sensor box 3 is inserted into the end face 2 and does not protrude beyond the end face 2 of the mold body 1. The sensor box 3 is located in the upper outer area of the mold plate or mold body 1 shown in order to prevent the sensors from overheating. The sensor box has a length sensor 18 for measuring the thickness of the mold body 1 .

The sensor box 3 has a cover 5 made of plastic, in particular Teflon. The base body 15 with the fastening tabs 16, 17 is arranged countersunk in a recess in the front side 2. The cover 5, which can be screwed to the front side 2 and the fastening tabs 16, 17 using screws 6, 7, is flush with the surface of the front side 2. This protects the sensor box 3 from mechanical damage.

The sensor box 3 contains a battery 8 and a control unit 9. The control unit 9 has a processor, a flash memory, a RAM memory as well as another sensor, which in this case is an acceleration sensor, and a second antenna. The second antenna is a BLE antenna. The NFC antenna 10 is arranged on the front of the sensor box 3, ie in the area of the cover 5. The NFC antenna 10 is used to wake up the sensors and initiate the data exchange upon first contact with a reader (not shown in detail).

The housing 4 of the sensor box 3 has a flange 20 adjacent to the cover 5, which extends to the casting side 19 of the mold body 1 in the installation position according to Figure 1. The flange 20 is completely covered by the cover 5, so that the cover 5 is wider than the base body 15 between the end fastening tabs 16, 17. The flange 20 extends over the entire length of the base body 15, whereby the longitudinal direction, i.e. the length, refers to the casting direction in the installation position. There is a gap 21 between the cover 5 and the flange 20 (Figure 3). The length sensor 18 is arranged in the gap 21 (Figure 2). In the installation position according to Figure 1, the flange 20 and the cover 5 with the length sensor 21 located between them protrude up to the casting side 19. When the casting side 19 is reworked, i.e. milled, material from the flange 20, material from the length sensor 18 and material from the cover 5 are removed at the same time. In the initial situation, the flange 20 and the cover 5 each have their narrow edges together with the length sensor 18 located between them flush with the casting side 19 (Figure 1). The cover 5 and the flange 20 hold the length sensor 18 and support it, especially during material-removing processing.

The length sensor 18 has conductor tracks that run at a distance from one another, the number of which decreases incrementally as material is removed. When the mold body 1 is reworked, the thickness of the mold body 1 is changed incrementally. These incremental changes are recorded by the length sensor 18 and the sensor box 3 and allow conclusions to be drawn about the thickness of the mold body 1.

Figure 5 shows an overall system for monitoring the mold body 1. A reading unit 11 in the form of a smartphone can scan a QR code 14 by means of a Camera reads and is also in wireless contact with the sensor box 3 on the mold body 1, evaluates the read data and transmits this to a server architecture 12 in order to supply the data for further processing. A customer portal 13 can be made available via the server architecture 12 in order to provide customers with mold-specific data.

Reference symbol:

1 - mold body

2 - Front side

3 - Sensor box

4 - Housing

5 - Lid

6 - Screw

7 - Screw

8 - Battery

9 - Control unit

10- N FC antenna

11 - Reading unit

12- Server architecture

13- Customer portal

14- QR code

15 - base body

16- mounting tab

17- Mounting tab

18- Length sensors

19- pouring side

20 - flange

21 - gap

Claims

patent claims 1. Mould body (1) with a sensor box (3) with the following features: a. The sensor box (3) has a length sensor system (18) for measuring a thickness of the mould body (1), wherein the length sensor system (18) has a plurality of conductor tracks arranged at a distance from one another in the thickness direction, wherein the sensor box (3) determines a measured value based on the number of conductor tracks present, which correlates with the thickness of the mould body (1), b. The sensor box (3) has an NFC antenna (10); c. The sensor box (3) has a control unit (9) and a battery (8); d. The control unit (9) has a processor, a flash memory, a RAM memory, at least one further sensor and a second antenna. 2. Mould body (1) according to claim 1, characterized in that the second antenna is a Bluetooth Low Energy antenna. 3. Mould body (1) according to claim 1 or 2, characterized in that the sensor box (3) has a housing (4) and a cover (5). 4. Mould body (1) according to claim 3, characterized in that the housing (4) consists of Teflon. 5. Mould body (1) according to one of claims 1 to 4, characterized in that it is a mould plate which has an end face (2) into which a base body (15) of the sensor box (3) is inserted, so that it is arranged at a distance from a casting side (19) of the mould plate (1), and wherein the length sensor (18) for measuring the thickness of the mould plate is arranged on a flange (20) of the sensor box (3) projecting towards the casting side (19). 6. Mould body (1) according to one of claims 1 to 5, characterized in that it has several sensor boxes (3). 7. Method for monitoring the mold body (1) according to one of claims 1 to 5, characterized in that the at least one further sensor detects an oscillation of the mold body (1) during casting, the time of the oscillation being stored. 8. The method according to claim 7, characterized in that the NFC antenna (10) is activated by a reading unit (11), wherein the NFC antenna (10) activates the control unit (9), wherein the control unit (9) establishes a connection between the control unit (9) and the reading unit (11) via the second antenna, whereupon a data transfer to the reading unit (11) takes place. 9. Method according to claim 8, characterized in that the data transfer comprises the transfer of a mold body ID stored in the control unit (9), which is checked in an evaluation unit of the readout unit (11) and, after successful checking, enables a further data transfer to the readout unit (11). 10. Method according to one of claims 7 to 9, characterized in that a wobbling movement of the mold body (1) is determined via the acceleration data read from several sensor boxes (3) of a single mold body (1).