A coke oven top scale calibration device and a method for reducing the production and delivery difference of a coke oven top scale by using the calibration device

Abstract

The present application relates to a kind of coke oven top scale calibration device, the calibration device includes weighing sensor, one PLC (4-20mA) interface, one RS232 communication serial port, one RS485 communication serial port, relay KM1 and relay KM2, a switch, several communication lines and two weighing instruments;Weighing sensor's input, analog quantity (4-20mA) output, RS232, RS485 four-way signal is connected with the normally closed upper end of relay KM1, KM2, and the lower end is connected with the corresponding interface of 1# instrument with four groups of communication lines, then it is connected with the normally open end of relay KM1, KM2 respectively through four groups of communication lines, and the other end of four groups of communication lines is connected with the corresponding 2# instrument;Switch S1 controls the action of relay KM1 and KM2 to switch two instruments.

Description

Technical Field

[0001] This invention relates to a calibration device, specifically a coke oven top scale calibration device, belonging to the technical field of calibration structural components. Background Technology

[0002] In modern coking, coal is transported to a hopper (hopper scale) by a conveyor belt. After being weighed, the coal is poured into a mobile weighing vehicle. The weighing sensor transmits the signal to the weighing instrument to obtain the weight data of the coal.

[0003] The furnace top scale is installed on a 20-meter-high rooftop, with a coking oven located 10 meters below. This places the scale in a high position with limited space. To meet production needs, the scale is mounted on two mobile weighing carts, which alternately weigh on the same measuring rail. If only one mobile weighing cart were operating, the step difference calibration (meaning dividing the scale length into sections and pressing objects of equal weight onto each section to achieve a step difference within ±0.5%) could be met. However, with two mobile weighing carts operating on the same measuring rail, the step difference calibration requirement cannot be met. This is because a single weighing instrument cannot simultaneously calibrate mobile weighing carts of different weights; it cannot correct the parameters of two carts, but can only adjust them to be as close as possible to obtain an approximate reading of the cart's weight. The furnace top scale has two 30-meter-long rails, each with 37 weighing sensors. When the scale is empty, the weighing trolley can move 180 tons, and the full scale is 212 tons. The calibration of the segmented weighing exceeds ±0.5%, resulting in a large discrepancy between material input costs and the production and sales difference of the output products, that is, low weighing accuracy. Therefore, there is an urgent need for a new solution to solve the above technical problems. Summary of the Invention

[0004] This invention addresses the problems existing in the prior art by providing a coke oven top scale calibration device. This technical solution has a simple structure, enables function switching, and ensures weighing accuracy.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: a coke oven top scale calibration device, the calibration device comprising a weighing sensor, a PLC (4-20mA) interface, an RS232 communication serial port, an RS485 communication serial port, relays KM1 and KM2, a switching switch, several communication lines, and two weighing instruments.

[0006] The weighing sensor's input, analog (4-20mA) output, RS232, and RS485 signals are connected to the normally closed upper terminals of relays KM1 and KM2. The lower terminals are connected to the corresponding interfaces of instrument #1 via four sets of communication lines. The four sets of communication lines are then connected to the normally open terminals of relays KM1 and KM2 respectively. The other ends of the four sets of communication lines are connected to the corresponding interfaces of instrument #2. The changeover switch S1 controls the operation of relays KM1 and KM2 to switch between the two instruments.

[0007] A method for reducing the production and sales difference of a coke oven top scale, using the aforementioned coke oven top scale calibration device, comprises the following steps:

[0008] Step 1: Install the electrical schematic diagram in the original instrument box, and install the rotary switch S1 in the control room of the No. 1 mobile weighing vehicle. The weighing instrument will be switched by the control room of the No. 1 mobile weighing vehicle.

[0009] Step 2: Turn the rotary switch S1 to the position connected to instrument #1. The load cell signal is output to instrument #1. When there is no load on the scale, instrument #1 will show a value of 0. If there is an error, clear the value to zero.

[0010] Step 3: When the No. 1 mobile weighing cart (furnace top scale) is empty, drive it to the bottom of the No. 1 unloading hopper, determine the weighing position, and the No. 1 instrument displays and records the tare weight value of the No. 1 mobile weighing cart (furnace top scale);

[0011] Step 4: Mark the load cells below the four wheel flanges and the metering rail contact points. This ballast point is called the first weighing position. When the scale is empty, the tare weight of the No. 1 mobile weighing car (furnace top scale) is the first segment weighing value.

[0012] Step 5: Move the No. 1 mobile weighing vehicle forward one vehicle distance, with the last two wheel flanges pressing against the positions of the two wheel flanges in front of the first weighing point. This ballast point is the second weighing position. If the No. 1 instrument displays an error in the second weighing value, find the bearing load cell number in the No. 1 instrument, adjust the coefficient of the single bearing load cell below the first two wheel flanges to meet the requirement of being within ±0.1% of the first and second weighing values, and record the second segment weighing value of the tare weight.

[0013] Step 6: Move the #1 mobile weighing cart back two distances away from the first weighing position when it is empty. That is, the two wheel flanges of the mobile weighing cart should be pressed against the first weighing position, and the two wheel flanges should be positioned to form the third weighing position. Adjust the coefficients of the two weighing sensors under the two wheel flanges until the weighing values ​​of the first and third segments are within ±0.1%.

[0014] Step 7: The No. 1 mobile weighing cart (furnace top scale) is removed from the scale, and then the first, second and third weighing positions are rechecked in the above order to see if the weighing values ​​of each weighing position meet the original recorded weighing values ​​of the three weighing points. Ensure that the weighing values ​​are within ±0.1%. At this point, the tare calibration operation of the No. 1 mobile weighing cart (furnace top scale) is completed and the cart is removed from the scale.

[0015] Step 8: After the No. 1 mobile weighing cart (furnace top scale) is fully loaded with standard weights at the stop weighing position, it is driven to the bottom of the No. 1 unloading hopper, which is also the first weighing position. The No. 1 instrument displays the gross weight (tare weight plus weight of the weights) of the No. 1 mobile weighing cart (furnace top scale). This gross weight is the first full load value. If the full load value exceeds the ±0.1% requirement, the total coefficient of the weighing sensor in the No. 1 instrument is corrected until the first full load value meets the ±0.1% requirement, and the weight value displayed by the No. 1 instrument is recorded.

[0016] Step 9: Move the No. 1 mobile weighing cart (furnace top scale) fully loaded with standard weights to the second weighing position first, and then to the third weighing position. Adjust the total coefficient of the correction weighing sensor in the No. 1 instrument to ensure that the full load value of the three weighing positions is within ±0.1%.

[0017] Step 10: The No. 1 mobile weighing cart (furnace top scale) is lowered and the weights are unloaded. At this point, the calibration of the No. 1 mobile weighing cart (furnace top scale) is completed.

[0018] Step 11: The #1 mobile weighing cart (furnace top scale) is lowered onto the scale. The rotary switch S1 in the control room is turned to the position connected to the #2 instrument. The #2 instrument is powered on and starts. The weighing sensor outputs a signal to the #2 instrument. At this time, the scale body has no load, and the #2 instrument has a value of 0. If there is an error, the value will be cleared to zero.

[0019] Step 12: When the #2 mobile weighing cart (furnace top scale) is empty, drive it to the bottom of the #1 unloading hopper and mark the first weighing position below the four wheel rims; the #2 instrument displays and records the tare weight value of the #2 mobile weighing cart (furnace top scale);

[0020] Step 13: When the No. 2 mobile weighing cart (furnace top scale) is empty and fully loaded, determine the three weighing positions, correct the tare weight weighing value, and adjust the full load value of the loaded weight. The order and requirements of calibration are the same as those of the No. 1 mobile weighing cart (furnace top scale).

[0021] In the above steps, when the weighing vehicle is empty and fully loaded with weights, the weighing position error of the wheel flange ballast does not exceed 0.5 meters.

[0022] In the above steps, the rotary switch (S1) is installed in the operating room of the No. 1 mobile weighing car (furnace top scale), which makes the switching of other instruments simple and reliable.

[0023] In the above steps, the second and third weighing values ​​and full-load values ​​of the mobile weighing cart (furnace top scale) are adjusted based on the first weighing value and full-load value.

[0024] In the above steps, the first weighing position is below the unloading hopper (hopper scale), the second and third weighing positions are one vehicle distance before and after the first weighing position, the rear wheel flange of the second weighing position is pressed against the front wheel flange of the first weighing point, and the front wheel flange of the third weighing position is pressed against the rear wheel flange of the first weighing point.

[0025] Compared with the prior art, the present invention has the following advantages: 1) The technical solution uses a rotary switch (S1) to control the relay, which transmits the sensor input signal to two weighing instruments, resulting in low modification cost and simple operation;

[0026] 2) This solution can determine the corresponding unloading bin for mobile weighing vehicles of different weights, thus avoiding feeding errors in the unloading bin itself;

[0027] 3) This scheme determines the weighing sensors of three weighing positions and ballast for mobile weighing carts (furnace top scales) of different weights. When reducing or shortening the segment calibration, large deviations occur in the segment difference values.

[0028] 4) The mobile weighing cart (furnace top scale) has three weighing positions. The first weighing position is the standard and is also the middle position of the three-segment ballast. There is a distance between the mobile weighing carts in front of and behind this position, which are the second and third weighing positions. This specification effectively controls the accuracy of the calibration value, and makes it easier and more accurate to correct the coefficient of the weighing sensor and the total coefficient of the weighing instrument, eliminating interference from other non-load-bearing and long-distance unloaded weighing sensors.

[0029] 5) This electrical control circuit enables the operation of a mobile weighing cart (furnace top scale) with multiple instruments on a single metering rail to weigh different weights, while meeting a weighing accuracy of ±0.5%.

[0030] 6) This technology also changes the previous erroneous method of using a single weighing instrument to measure mobile weighing vehicles of different weights, which resulted in a large discrepancy between material usage and output.

[0031] 7) One weighing instrument weighs one mobile weighing vehicle, which also changes the previous method of calibrating mobile weighing vehicles with different self-weights, and cannot eliminate the weighing error caused by weight difference.

[0032] 8) This technology requires low investment and does not require improvements to weighing equipment. Simply extending the calibration time can improve the accuracy of weighing. Attached Figure Description

[0033] Figure 1 A schematic diagram of the actual calibration of the coke oven top scale;

[0034] Figure 2This is a schematic diagram of electrical principles;

[0035] Figure 3 This is a schematic diagram of electrical principle two;

[0036] Figure 4 Electrical Principles III Schematic Diagram

[0037] Figure 5 This is a schematic diagram of electrical principle four.

[0038] In the diagram: 1-1# Feeding bin 2-2# Feeding bin 3-1# Mobile weighing cart 4-2# Mobile weighing cart 5- Weighing sensor 6- Metering rail 7- Rotary switch (S1) or (S2) 8- Weight 9-1# Instrument 10-2# Instrument. Detailed implementation method:

[0039] To enhance understanding of the present invention, the embodiments will be described in detail below with reference to the accompanying drawings.

[0040] Example 1: See Figures 1-5 A coke oven top scale calibration device, the calibration device includes a weighing sensor, a PLC (4-20mA) interface, an RS232 communication serial port, an RS485 communication serial port, relays KM1 and KM2, a switch, several communication lines and two weighing instruments.

[0041] The weighing sensor's input, analog (4-20mA) output, RS232, and RS485 signals are connected to the normally closed upper terminals of relays KM1 and KM2. The lower terminals are connected to the corresponding interfaces of instrument #1 via four sets of communication lines. The four sets of communication lines are then connected to the normally open terminals of relays KM1 and KM2 respectively. The other ends of the four sets of communication lines are connected to the corresponding interfaces of instrument #2. The changeover switch S1 controls the operation of relays KM1 and KM2 to switch between the two instruments.

[0042] Example 2: See Figures 1-5 A method for reducing the production and sales difference of a coke oven top scale, using the aforementioned coke oven top scale calibration device, comprises the following specific steps:

[0043] Step 1: Refer to the appendix Figure 4 The electrical schematic diagram was installed in the original instrument box, and the rotary switch S1 was installed in the control room of the No. 1 mobile weighing vehicle. The weighing instrument was switched by the control room of the No. 1 mobile weighing vehicle.

[0044] Step 2: Turn the rotary switch S1 to the position connected to instrument #1. The load cell signal is output to instrument #1. When there is no load on the scale, instrument #1 will show a value of 0. If there is an error, clear the value to zero.

[0045] Step 3: When the No. 1 mobile weighing cart (furnace top scale) is empty, drive it to the bottom of the No. 1 unloading hopper, determine the weighing position, and the No. 1 instrument displays and records the tare weight value of the No. 1 mobile weighing cart (furnace top scale);

[0046] Step 4: Mark the load cells below the four wheel flanges and the metering rail contact points. This ballast point is called the first weighing position. When the scale is empty, the tare weight of the No. 1 mobile weighing car (furnace top scale) is the first segment weighing value.

[0047] Step 5: Move the No. 1 mobile weighing vehicle forward one vehicle distance, with the last two wheel flanges pressing against the positions of the two wheel flanges in front of the first weighing point. This ballast point is the second weighing position. If the No. 1 instrument displays an error in the second weighing value, find the bearing load cell number in the No. 1 instrument, adjust the coefficient of the single bearing load cell below the first two wheel flanges to meet the requirement of being within ±0.1% of the first and second weighing values, and record the second segment weighing value of the tare weight.

[0048] Step 6: Move the #1 mobile weighing cart back two distances away from the first weighing position when it is empty. That is, the two wheel flanges of the mobile weighing cart should be pressed against the first weighing position, and the two wheel flanges should be positioned to form the third weighing position. Adjust the coefficients of the two weighing sensors under the two wheel flanges until the weighing values ​​of the first and third segments are within ±0.1%.

[0049] Step 7: The No. 1 mobile weighing cart (furnace top scale) is removed from the scale, and then the first, second and third weighing positions are rechecked in the above order to see if the weighing values ​​of each weighing position meet the original recorded weighing values ​​of the three weighing points. Ensure that the weighing values ​​are within ±0.1%. At this point, the tare calibration operation of the No. 1 mobile weighing cart (furnace top scale) is completed and the cart is removed from the scale.

[0050] Step 8: After the No. 1 mobile weighing cart (furnace top scale) is fully loaded with standard weights at the stop weighing position, it is driven to the bottom of the No. 1 unloading hopper, which is also the first weighing position. The No. 1 instrument displays the gross weight (tare weight plus weight of the weights) of the No. 1 mobile weighing cart (furnace top scale). This gross weight is the first full load value. If the full load value exceeds the ±0.1% requirement, the total coefficient of the weighing sensor in the No. 1 instrument is corrected until the first full load value meets the ±0.1% requirement, and the weight value displayed by the No. 1 instrument is recorded.

[0051] Step 9: Move the No. 1 mobile weighing cart (furnace top scale) fully loaded with standard weights to the second weighing position first, and then to the third weighing position. Adjust the total coefficient of the correction weighing sensor in the No. 1 instrument to ensure that the full load value of the three weighing positions is within ±0.1%.

[0052] Step 10: The No. 1 mobile weighing cart (furnace top scale) is lowered and the weights are unloaded. At this point, the calibration of the No. 1 mobile weighing cart (furnace top scale) is completed.

[0053] Step 11: The #1 mobile weighing cart (furnace top scale) is lowered onto the scale. The rotary switch S1 in the control room is turned to the position connected to the #2 instrument. The #2 instrument is powered on and starts. The weighing sensor outputs a signal to the #2 instrument. At this time, the scale body has no load, and the #2 instrument has a value of 0. If there is an error, the value will be cleared to zero.

[0054] Step 12: When the #2 mobile weighing cart (furnace top scale) is empty, drive it to the bottom of the #1 unloading hopper and mark the first weighing position below the four wheel rims; the #2 instrument displays and records the tare weight value of the #2 mobile weighing cart (furnace top scale);

[0055] Step 13: When the No. 2 mobile weighing cart (furnace top scale) is empty and fully loaded, determine the three weighing positions, correct the tare weight weighing value, and adjust the full load value of the loaded weight. The order and requirements of calibration are the same as those of the No. 1 mobile weighing cart (furnace top scale).

[0056] In the above steps, when the weighing vehicle is empty and fully loaded with weights, the weighing position error of the wheel flange ballast does not exceed 0.5 meters.

[0057] In the above steps, the rotary switch (S1) is installed in the operating room of the No. 1 mobile weighing car (furnace top scale), which makes the switching of other instruments simple and reliable.

[0058] In the above steps, the second and third weighing values ​​and full-load values ​​of the mobile weighing cart (furnace top scale) are adjusted based on the first weighing value and full-load value.

[0059] In the above steps, the first weighing position is below the unloading hopper (hopper scale), the second and third weighing positions are one vehicle distance before and after the first weighing position, the rear wheel flange of the second weighing position is pressed against the front wheel flange of the first weighing point, and the front wheel flange of the third weighing position is pressed against the rear wheel flange of the first weighing point.

[0060] Working principle: See Figure 1 — Figure 5 ,

[0061] 1. The sensor output signal is sent to instrument #1 via the normally closed terminal of relay (KM1), and the rotary switch (S1) is in the off state.

[0062] 2. The signal output from instrument #1 is transmitted to the PLC (4-20mA) module, RS232 communication serial port and RS485 communication serial port via relay (KM1).

[0063] 3. When the rotary changeover switch (S1) is turned on, the coils of relays (KM1) and (KM2) are energized, the relays are activated, the input and output signals of instrument #1 are interrupted, and the input and output signals are connected to instrument #2 via relays (KM1 and KM2).

[0064] 4. The signal output from instrument #2 is transmitted to the PLC (4-20mA) module, RS232 communication serial port and RS485 communication serial port via relay (KM2).

[0065] 5. Similarly, by rotating the selector switch (S1) or (S2), the relay is switched to achieve the same series of load cells transmitting signals for objects of different weights, which are then recorded by multiple weighing instruments, eliminating calibration errors and improving weighing accuracy. Figure 4 ).

[0066] The coke oven top scale used in our unit consists of two mobile weighing carts with different weights, moving along a metering rail for loading and unloading. A single weighing instrument measures the weight of the furnace charge. Previously, calibrating the two mobile weighing carts with different weights involved driving them to the same weighing position on the metering rail. No matter how the instrument was adjusted, it was impossible to make both carts meet the ±0.5% calibration requirement, let alone modify the mobile weighing carts (furnace top scale) to have the same weight. This resulted in a large discrepancy between input and output, and also contributed to the significant differences in cost accounting between large-scale metallurgical projects both domestically and internationally. This new technology involves modifying the electrical equipment and adding a weighing instrument. A switch is used to switch between the corresponding weighing instruments on the mobile weighing carts (furnace top scale). Three weighing positions are specified during calibration, determining the empty and full load conditions, and methods for correcting the pressure sensor coefficient and adjusting the overall instrument coefficient to avoid operational errors. The application of this technology in the coke oven top weighing system not only improves weighing accuracy and optimizes calibration methods, eliminating the problem of large calibration errors in mobile weighing vehicles, but also shortens the input-output gap and reduces the investment of manpower and material resources.

[0067] It should be noted that the above embodiments are not intended to limit the scope of protection of the present invention. Equivalent transformations or substitutions made based on the above technical solutions all fall within the scope of protection of the claims of the present invention.

Claims

1. A method of reducing the coke balance of a coke oven battery, characterized in that, A coke oven top scale calibration device is used. The calibration device includes a load cell, a PLC interface, an RS232 communication serial port, an RS485 communication serial port, relays KM1 and KM2, a changeover switch, several communication lines, and two weighing instruments. The input, analog output, RS232, and RS485 signals of the load cell are connected to the normally closed upper terminals of relays KM1 and KM2. The lower terminals are connected to the corresponding interfaces of instrument #1 via four sets of communication lines. These four sets of communication lines are then connected to the normally open terminals of relays KM1 and KM2, respectively. The other ends of the four sets of communication lines are connected to instrument #2. The changeover switch S1 controls the operation of relays KM1 and KM2 to switch between the two instruments. The method includes the following steps: Step 1: Install the electrical schematic diagram in the original instrument box, and install the rotary switch S1 in the control room of the No. 1 mobile weighing vehicle. The weighing instrument will be switched by the control room of the No. 1 mobile weighing vehicle. Step 2: Turn the rotary switch S1 to the position connected to instrument #1. The load cell signal is output to instrument #1. When there is no load on the scale, instrument #1 will show a value of 0. If there is an error, clear the value to zero. Step 3: When the #1 mobile weighing cart is empty, drive it to the bottom of the #1 unloading hopper, determine the weighing position, and the #1 instrument displays and records the tare weight value of the #1 mobile weighing cart. Step 4: Mark the load cells below the four wheel flanges and the metering rail contact points. This ballast point is called the first weighing position. When the scale is empty, the tare weight of the No. 1 mobile weighing vehicle is the first segment weighing value. Step 5: Move the No. 1 mobile weighing vehicle forward one vehicle distance, with the last two wheel flanges pressing against the positions of the two wheel flanges in front of the first weighing point. This ballast point is the second weighing position. If the No. 1 instrument displays an error in the second weighing value, find the bearing load cell number in the No. 1 instrument, adjust the coefficient of the single bearing load cell under the first two wheel flanges to achieve the requirement of being within ±0.1% of the first and second weighing values, and record the second segment weighing value of the tare weight. Step 6: Move the #1 mobile weighing cart back two distances away from the first weighing position when it is empty. That is, the two wheel flanges of the mobile weighing cart should be pressed against the first weighing position, and the two wheel flanges should be positioned to form the third weighing position. Adjust the coefficients of the two weighing sensors under the two wheel flanges until the weighing values ​​of the first and third segments are within ±0.1%. Step 7: Remove the #1 mobile weighing cart from the scale, and then recheck the first, second and third weighing positions in the above order to see if each weighing value meets the original recorded weighing value of the three weighing points, ensuring that each weighing value is within ±0.1%. At this point, the tare weight calibration operation of the #1 mobile weighing cart is completed and it is removed from the scale. Step 8: After the #1 mobile weighing cart is fully loaded with standard weights at the stopping position, it moves to the area below the #1 unloading hopper, which is also the first weighing position. The #1 instrument displays the gross weight value of the #1 mobile weighing cart. This gross weight is the first full load value. If the full load value exceeds the ±0.1% requirement, the total coefficient of the weighing sensor in the #1 instrument is corrected until the first full load value meets the ±0.1% requirement, and the weight value displayed by the #1 instrument is recorded. Step 9: Move the No. 1 mobile weighing cart, fully loaded with standard weights, to the second weighing position first, then to the third weighing position. Adjust the total coefficient of the weighing sensor in the No. 1 instrument to ensure that the full load value of the three weighing positions is within ±0.1%. Step 10: Unload the weights from the #1 mobile weighing cart. The calibration of the #1 mobile weighing cart is now complete. Step 11: The #1 mobile weighing vehicle is removed from the scale. The rotary switch S1 in the control room is turned to the position connected to the #2 instrument. The #2 instrument is powered on and starts. The load cell outputs a signal to the #2 instrument. At this time, there is no load on the scale body and the #2 instrument shows a value of 0. If there is an error, the value will be reset to zero. Step 12: When the #2 mobile weighing cart is empty, drive it to the bottom of the #1 unloading hopper and mark the first weighing position below the four wheel flanges; the #2 instrument displays and records the tare weight value of the #2 mobile weighing cart. Step 13: When the #2 mobile weighing vehicle is empty and fully loaded, determine the three weighing positions, correct the tare weight value, and adjust the full load value of the loaded weights. The order and requirements of calibration are the same as those for the #1 mobile weighing vehicle.

2. A method of reducing the loss in weight of coke from the coke oven battery as claimed in claim 1 wherein, In the above steps, when the weighing vehicle is empty and fully loaded with weights, the weighing position error of the wheel flange ballast should not exceed 0.5 meters.

3. A method of reducing the loss of coke from the coke balance of a coke oven battery as claimed in claim 2, wherein, In the above steps, Rotary switch S1 is installed in the No. 1 mobile weighing control room.

4. A method of reducing the loss of coke from the coke hoppers of a coke oven battery as claimed in claim 3, wherein In the above steps, The second and third weighing values ​​and full load values ​​of the mobile weighing vehicle are adjusted based on the first weighing value and full load value.

5. A method of reducing the loss of coke from the coke hoppers of a coke oven battery as claimed in claim 4, wherein, In the above steps, the first weighing position is below the unloading hopper, the second and third weighing positions are one vehicle distance before and after the first weighing position, the rear wheel flange of the second weighing position is pressed against the front wheel flange of the first weighing point, and the front wheel flange of the third weighing position is pressed against the rear wheel flange of the first weighing point.

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