Slab continuous casting swing oil cylinder double-position sensor control method

Abstract

The invention relates to the technical field of slab continuous casting sensors, in particular to a slab continuous casting swing oil cylinder double-position sensor control method, which comprises the following steps of: synchronously acquiring position data through double sensors, checking signal validity in real time through a PLC (Programmable Logic Controller), immediately switching to a normal signal and triggering an alarm if a fault is detected, periodically checking switching logic through a self-checking module, and automatically checking the switching logic. And the maintenance module prompts preventive maintenance according to the operation data to ensure continuous and stable operation of the system. The problems that a position sensor is installed in an oil cylinder of an existing swing frame and used for controlling the swing speed of the oil cylinder to be matched with the continuous casting pulling speed, once the position sensor breaks down, a swing shear cannot operate normally, and serious accidents of continuous casting production interruption are caused are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of slab continuous casting sensors, and specifically refers to a control method for double-position sensors of swing cylinders in slab continuous casting. Background Art

[0002] The CSP continuous casting swing shear is a key equipment to ensure continuous casting production. When the swing shear cuts, the swing cylinder of the frame swings with the continuous casting drawing speed to ensure that the swing shear can smoothly cut the cast slab. A position sensor is installed in the swing frame cylinder to control the swing speed of the cylinder to match the continuous casting drawing speed. Once this position sensor fails, the swing shear will not be able to operate normally, resulting in a serious accident of interrupting continuous casting production. Summary of the Invention

[0003] The technical problem to be solved by the present invention is that there is a position sensor installed in the existing swing frame cylinder to control the swing speed of the cylinder to match the continuous casting drawing speed. Once this position sensor fails, the swing shear will not be able to operate normally, resulting in a serious accident of interrupting continuous casting production.

[0004] To solve the above problems, the technical solution adopted by the present invention is a control method for double-position sensors of swing cylinders in slab continuous casting, including a double-sensor module: respectively installed on the dummy cylinders of the left and right cylinders of the swing shear, and each module includes a position sensor and a signal transmission unit for real-time acquisition of cylinder position data;

[0005] A PLC control unit: configured with a dual-channel data interface to synchronously receive the position signals of the double-sensor module and execute the following logic: perform validity verification on the two signals, including signal range judgment, change rate monitoring, and cross-difference comparison; when any one signal is determined to be faulty, automatically switch to the other normal signal as the control basis for the swing shear;

[0006] A fault alarm module: connected to the PLC control unit to output an alarm signal when a signal switch occurs.

[0007] Furthermore, the position sensor is an absolute encoder or a linear displacement sensor, and the ranges, resolutions, and installation positions of the two sensors are the same to ensure the synchronism and comparability of data acquisition;

[0008] Furthermore, the validity verification logic executed by the PLC control unit specifically includes: determining whether the signal exceeds the preset physical stroke range; calculating the change amount of the signal per unit time, and if it exceeds the threshold, it is determined to be abnormal; periodically comparing the absolute value of the difference between the two signals, and if it exceeds ±0.5% of the stroke, a switch is triggered;

[0009] Further, the fault alarm module is implemented in the following manner. A fault flag bit is set in the PLC control unit and set when a signal switch occurs. An external audible and visual alarm is driven through a digital output port, or an alarm message is sent to the host computer via the industrial Ethernet.

[0010] The advantages of the present invention compared with the prior art are as follows:

[0011] Now, a dummy cylinder with a position sensor is installed on each of the left and right cylinders of the swing shear. It moves synchronously with the swing shear cylinder. Once a fault occurs in one of the position sensors, it is automatically switched to another normal position sensor through the PLC program, thus ensuring the normal function of the swing shear and maintaining the normal production of continuous casting. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings are used to provide a further understanding of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation to the present invention. In the drawings:

[0013] Figure 1 It is a PLC control diagram in a method for controlling a swing cylinder of a slab continuous casting with a dual position sensor according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the scope of protection of the present invention.

[0015] The present invention provides a technical solution: to solve the existing problems proposed in the background art.

[0016] It includes a dual-sensor module: respectively installed on the dummy cylinders of the left and right cylinders of the swing shear. Each module includes a position sensor and a signal transmission unit for real-time acquisition of cylinder position data.

[0017] A PLC control unit: configured with a dual-channel data interface to synchronously receive the position signals of the dual-sensor module and execute the following logic: perform validity verification on the two signals, including signal range judgment, change rate monitoring, and mutual difference comparison; when any one of the signals is determined to be faulty, automatically switch to the other normal signal as the basis for swing shear control.

[0018] A fault alarm module: connected to the PLC control unit to output an alarm signal when a signal switch occurs.

[0019] Further, the position sensors are absolute encoders or linear displacement sensors, and the ranges, resolutions, and installation positions of the two sensors are the same to ensure the synchronization and comparability of data acquisition;

[0020] Further, the validity check logic executed by the PLC control unit specifically includes: determining whether the signal exceeds the preset physical stroke range; calculating the change amount of the signal per unit time, and determining it as abnormal if it exceeds the threshold; periodically comparing the absolute value of the difference between the two signals, and triggering a switch if it exceeds ±0.5% of the stroke;

[0021] Further, the fault alarm module is implemented in the following way. A fault flag bit is set in the PLC control unit, which is set when a signal switch occurs, and an external acoustic-optic alarm is driven through a digital output port, or an alarm message is sent to the upper computer through the industrial Ethernet.

[0022] The working process of this application is as follows:

[0023] When the system starts, the dual-sensor module synchronously collects the false cylinder position data of the left and right cylinders of the swing shear and sends it to the PLC control unit through the independent signal transmission unit. After receiving the two position signals in real time, the PLC control unit first performs a validity check, including determining whether the signal is within the preset stroke range, monitoring whether the change rate per unit time is abnormal, and periodically comparing whether the absolute value of the difference between the two signals exceeds ±0.5% of the stroke. If any signal check fails, it is determined as a fault and immediately switched to the other normal signal as the basis for swing shear control. At the same time, the fault alarm module is triggered to drive an external acoustic-optic alarm through a digital output port or send an alarm message to the upper computer through the industrial Ethernet. In addition, the built-in self-check module in the system will periodically simulate sensor faults to verify the effectiveness of the PLC switching logic, record the switching response time to generate a self-check report, the signal transmission unit uses a twisted pair shielded cable and a digital filter at the PLC input end to achieve anti-interference design, and the maintenance prompt module generates maintenance suggestions based on the sensor operation time or the number of faults. When the cumulative operation duration is close to the design life or the failure rate per unit time exceeds the threshold, it prompts for preventive maintenance. The entire process ensures that the swing shear system can still operate continuously and stably when a single sensor fails.

[0024] The above describes the present invention and its implementation manners. This description is not restrictive. What is shown in the drawings is only one of the implementation manners of the present invention. The actual structure is not limited to this. Generally speaking, if those of ordinary skill in the art are inspired by it and without departing from the purpose of the present invention creation, they design similar structural manners and embodiments to this technical solution without creative efforts, which should all fall within the protection scope of the present invention.

Claims

1. A control method for a double-position sensor of a swing oil cylinder in slab continuous casting, characterized in that: It includes a double-sensor module: respectively installed on the dummy oil cylinders of the left and right oil cylinders of the swing shear. Each module contains a position sensor and a signal transmission unit, which are used to collect the oil cylinder position data in real time; A PLC control unit: configured with a dual-channel data interface, synchronously receiving the position signals of the double-sensor module, and executing the following logic: performing validity verification on the two signals, including signal range judgment, change rate monitoring, and cross-difference comparison; when any signal is determined to be faulty, automatically switch to the other normal signal as the basis for swing shear control; A fault alarm module: connected to the PLC control unit, and outputting an alarm signal when a signal switch occurs.

2. A control method for a slab continuous casting swing oil cylinder with dual position sensors according to claim 1, characterized in that: The position sensor is an absolute encoder or a linear displacement sensor, and the measuring ranges, resolutions, and installation positions of the two sensors are the same to ensure the synchronism and comparability of data collection.

3. A control method for a slab continuous casting swing oil cylinder with dual position sensors according to claim 1, characterized in that: The validity verification logic executed by the PLC control unit specifically includes: determining whether the signal exceeds the preset physical stroke range; calculating the change amount of the signal per unit time, and if it exceeds the threshold, it is determined to be abnormal; periodically comparing the absolute value of the difference between the two signals, and if it exceeds ±0.5% of the stroke, a switch is triggered.

4. A control method for a slab continuous casting swing oil cylinder with dual position sensors according to claim 1, characterized in that: The fault alarm module is implemented in the following way: setting a fault flag bit in the PLC control unit, setting it when a signal switch occurs, driving an external audible and visual alarm through a digital quantity output port, or sending an alarm message to the upper computer through an industrial Ethernet.

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