阅读说明：本技术 一种射线式测厚仪及其温度补偿系数计算方法 (Ray type thickness gauge and temperature compensation coefficient calculation method thereof ) 是由 喻尧 孔祥兵 郑旭涛 马明 付有彭 王诗 鲍振振 马帅 杜栓林 孙运涛 于 2021-08-30 设计创作，主要内容包括：本发明公开了一种射线式测厚仪温度补偿系数计算方法,属于钢铁生产领域,包括：步骤(1)获取温度补偿系数K；步骤(2)设定偏差限幅值；步骤(3)获取数字量温度信号；步骤(4)温度补偿；步骤(5)带钢冷态厚度值获得。与现有技术相比较,本发明可以提高厚度检测精度,避免异常温度带影响厚度计算及检测,达到准确测量带钢厚度、凸度和楔形的目的,同时提高产品质量和生产稳定性。(The invention discloses a method for calculating a temperature compensation coefficient of a radial thickness gauge, which belongs to the field of steel production and comprises the following steps: the method comprises the following steps of (1) obtaining a temperature compensation coefficient K; step (2) setting a deviation amplitude limit value; step (3) acquiring a digital quantity temperature signal; temperature compensation is carried out; and (5) obtaining the cold-state thickness value of the strip steel. Compared with the prior art, the thickness detection precision can be improved, the influence of an abnormal temperature zone on thickness calculation and detection is avoided, the purpose of accurately measuring the thickness, the convexity and the wedge shape of the strip steel is achieved, and meanwhile, the product quality and the production stability are improved.)

1. A method for calculating a temperature compensation coefficient of a radial thickness gauge is characterized by comprising the following steps: the method comprises the following steps:

step (1): obtaining a temperature compensation coefficient K

Let S₂Is the thermal state thickness value S under different temperature values₁For the cold-state thickness value of the strip steel, the formula (1) of the temperature compensation coefficient and the cold-state thickness of the strip steel can be expressed as follows:

K＝(S₂-S₁)/S₁；

taking a standard thickness sample plate, heating to different temperatures under a laboratory condition, measuring the thickness of the standard sample plate by using a radial thickness gauge under the condition of canceling temperature compensation to obtain compensation coefficients under different temperatures, and fitting the compensation coefficients and temperature values into a sextic polynomial curve to obtain an expression formula (2) of the temperature compensation coefficients and the temperature: 1.082e^-18*t⁶-4.054e^-15*t⁵+6e^-12*t⁴-3.065e^-9*t³-1e^-6*t²+0.0015t+0.596

Writing the formula (1) and the formula (2) into a temperature compensation program of a control system of the thickness gauge;

step (2): setting a deviation margin

Setting a deviation limit value in a temperature compensation program of a thickness gauge control system;

and (3): obtaining a digital temperature signal

The pyrometer is used for measuring surface radiation heat energy in the width direction of the strip steel, measuring signals are transmitted to a temperature measuring system processor, the measured temperature value is amplified and subjected to A/D conversion, and digital quantity temperature signals are transmitted to a temperature measuring control system;

and (4): temperature compensation

The temperature data of each point of the cross section acquired in the step (3) is accessed into the temperature compensation program of the control system of the thickness gauge in the step (1);

if the temperature in the width direction does not exceed the deviation limit value set in the step (2), calculating the temperature compensation coefficient of each point in the width direction according to the formula (2);

if the temperature in the width direction exceeds the set deviation limiting value in the step (2), substituting the average value of the temperature in the width direction into the formula (2) to calculate the temperature compensation coefficient of the point;

and (5): obtaining the cold thickness value of the strip steel

And (5) substituting the temperature compensation coefficient obtained in the step (4) into the formula (1) to obtain the thickness of the strip steel at each point on the cross section in the cold state.

2. The method for calculating the temperature compensation coefficient of the radial thickness gauge according to claim 1, wherein: the deviation limiting value in the step (2) is 20 ℃.

3. The method for calculating the temperature compensation coefficient of the radial thickness gauge according to claim 1, wherein: and (5) calculating to obtain correct thickness, convexity and wedge values according to the thickness of the cold-state strip steel in the step (5).

Technical Field

The invention relates to a measurement and calculation method, in particular to a radial thickness gauge suitable for strip steel thickness detection and a temperature compensation coefficient calculation method thereof.

Background

Steel rolling is an important link for producing steel by steel enterprises, the thickness is a key for determining the quality of steel, the thickness of strip steel is not as long as the length and the width, the strip steel can be cut and processed according to the requirements of customers, and the thickness of the strip steel must be accurately detected and controlled in the rolling process, so that a high-precision thickness gauge must be adopted in the production process to detect the thickness of the strip steel in real time. When the radial type thickness gauge is used for measuring the thickness, a hot-state thickness detection value of the strip steel needs to be converted into a cold-state thickness value, a temperature compensation coefficient used in an algorithm is calculated according to the temperature measured by a single-point type pyrometer in the thickness gauge, but in a thin slab continuous casting and rolling production line, because a traditional gas heating furnace is not arranged in front of a rough rolling frame for heating, the problem of uneven temperature distribution generally exists in the transverse direction of the strip steel, if the strip steel temperature in a detection area of the point type pyrometer is abnormal, the strip steel temperature compensation coefficient is calculated according to the temperature compensation coefficient, the phenomenon that the deviation is overlarge in the cold-state thickness value conversion process is inevitably caused, the strip steel thickness, the convexity and the wedge shape calculated according to the temperature compensation coefficient can generate larger errors, and the strip steel shape and the quality are not favorably controlled.

Therefore, the company develops a temperature compensation method and a temperature compensation device for improving the detection precision of the radial thickness gauge (application number CN202011579550.5), the equipment comprises the thickness gauge and a scanning pyrometer, the scanning pyrometer detects the temperature on the whole cross section of the strip steel, the collected signals are accessed into a special processor for processing, the signals are transmitted to a thickness gauge control system through a serial port or an Ethernet and other modes, and the temperature compensation calculation program block in the thickness gauge control system is utilized to calculate the temperature compensation coefficient of each point in the width direction; and sets an offset value to correct the data. However, the formula of the temperature compensation calculation method of the equipment adopts a calculation method in an inherent calculation program block in a thickness gauge control system, the calculation method takes single-point calculation as background, and in the actual production process, the coefficient calculation formula is applied to multi-point calculation, so that the deviation from the actual result is large.

Therefore, a method for detecting the temperature and calculating the temperature compensation coefficient of the radial-type thickness gauge suitable for the continuous casting and rolling production line of the thin slab is urgently needed.

Disclosure of Invention

The technical task of the invention is to provide a method for detecting the temperature and calculating the temperature compensation coefficient of the radial thickness gauge, aiming at the defects of the prior art, so as to improve the thickness detection precision, avoid the influence of an abnormal temperature zone on the thickness calculation and detection, achieve the aim of accurately measuring the thickness, the convexity and the wedge shape of the strip steel, and simultaneously improve the product quality and the production stability.

The technical scheme for solving the technical problem is as follows: a method for calculating a temperature compensation coefficient of a radial thickness gauge is characterized by comprising the following steps: the method comprises the following steps:

step (1): obtaining a temperature compensation coefficient K

Let S₂Is the thermal state thickness value S under different temperature values₁For the cold-state thickness value of the strip steel, the formula (1) of the temperature compensation coefficient and the cold-state thickness of the strip steel can be expressed as follows:

K＝(S₂-S₁)/S₁；

taking a standard thickness sample plate, heating to different temperatures under a laboratory condition, measuring the thickness of the standard sample plate by using a radial thickness gauge under the condition of canceling temperature compensation to obtain compensation coefficients under different temperatures, and fitting the compensation coefficients and temperature values into a sextic polynomial curve to obtain an expression formula (2) of the temperature compensation coefficients and the temperature: 1.082e^-18*t⁶-4.054e^-15*t⁵+6e^-12*t⁴-3.065e^-9*t³-1e^-6*t²+0.0015t+0.596

Writing the formula (1) and the formula (2) into a temperature compensation program of a control system of the thickness gauge;

step (2): setting a deviation margin

Setting a deviation limit value in a temperature compensation program of a thickness gauge control system;

and (3): obtaining a digital temperature signal

The pyrometer is used for measuring surface radiation heat energy in the width direction of the strip steel, measuring signals are transmitted to a temperature measuring system processor, the measured temperature value is amplified and subjected to A/D conversion, and digital quantity temperature signals are transmitted to a temperature measuring control system;

and (4): temperature compensation

The temperature data of each point of the cross section acquired in the step (3) is accessed into the temperature compensation program of the control system of the thickness gauge in the step (1);

if the temperature in the width direction does not exceed the deviation limit value set in the step (2), calculating the temperature compensation coefficient of each point in the width direction according to the formula (2);

if the temperature in the width direction exceeds the set deviation limiting value in the step (2), substituting the average value of the temperature in the width direction into the formula (2) to calculate the temperature compensation coefficient of the point;

and (5): obtaining the cold thickness value of the strip steel

And (5) substituting the temperature compensation coefficient obtained in the step (4) into the formula (1) to obtain the thickness of the strip steel at each point on the cross section in the cold state.

In an optimized scheme, the deviation limiting value in the step (2) is 20 ℃.

In the optimization scheme, the correct thickness, convexity and wedge value are calculated according to the thickness of the strip steel in the cold state in the step (5).

Compared with the prior art, the invention has the following outstanding beneficial effects:

1. according to the invention, the calculation method of the temperature compensation coefficient in the system is innovated, so that the thickness detection precision is improved, the influence of an abnormal temperature zone on thickness calculation and detection is avoided, and the purpose of accurately measuring the thickness, the convexity and the wedge shape of the strip steel is achieved;

2. the invention avoids the influence of abnormal thickness on the product quality and steel scrap accidents, reduces the proportion of defective and defective products caused by abnormal thickness, improves the product quality and production stability and increases the economic benefit.

Drawings

Fig. 1 is a schematic structural view of the ray thickness gauge of the present invention.

FIG. 2 is a schematic diagram of the structure of the pyrometer of the present invention.

Detailed Description

The invention is further described with reference to the drawings and the detailed description.

The invention provides a ray-type thickness gauge and a temperature compensation coefficient calculation method thereof. In this embodiment, the radial thickness gauge is installed at the outlet of the finishing mill in the continuous casting and rolling production line of thin slabs and is a device for detecting the final thickness of rolled strip steel.

As shown in fig. 1, the ray thickness gauge includes a ray source 1, an ionization chamber 2, a C-shaped frame 3 and a central control unit. The number of the ray sources 1 and the ionization chambers 2 is multiple.

The radiation source 1 is arranged on the upper arm of the C-shaped frame 3, the ionization chamber 2 is arranged below the lower arm of the C-shaped frame 3, and the strip steel 4 is positioned between the upper arm and the lower arm of the C-shaped frame 3. The ionization chamber 2 is in data connection with a central control unit. The ionization chamber 2 receives ionization energy passing through the strip steel, and the central control unit is used for displaying and receiving instructions of an operator, converting received signals and calculating thickness. The upper arm of the C-shaped frame 3 is also provided with an altimeter which is in data connection with the central control unit, the altimeter comprises a scanning pyrometer 5 and a single-point altimeter 6, and the scanning pyrometer 5 is arranged in the middle of the upper arm of the C-shaped frame 3. The central control unit comprises a temperature measurement system processor and a temperature measurement control system. In this embodiment, an M-client control system of the thickness gauge is adopted. The scanning pyrometer 5 and the single-point altimeter 6 are designed to effectively prevent abnormal deviation, namely the scanning pyrometer 5 is a main data source, the single-point altimeter 6 is a review data source, and when the data of the same measuring point and the data of the two significantly deviate, manual review is prompted to switch the high-temperature counting data, so that the error of calculating the compensation coefficient is prevented.

As shown in FIG. 2, an air blowing device 8 with a cooling air pipe 7 is connected below a measuring window of the pyrometer, and a blowing air port 9 of the air blowing device 8 is connected with the bottom of the pyrometer through a fixing bolt, so that the detection of the pyrometer is prevented from being interfered by on-site water vapor and dust.

The shell of the pyrometer is provided with an interlayer, and the interlayer is provided with a water inlet and a water outlet which are used for connecting a cooling water pipe 10 and used for cooling the pyrometer body.

Except for special description, the hardware and the operation control system have different specifications and data connection modes due to different models, and the specific connection mode and the data acquisition, conversion and processing mode are not described in the prior art again.

The method for calculating the temperature compensation coefficient of the radial thickness gauge comprises the following steps:

step (1): obtaining a temperature compensation coefficient K

Let S₂Is the thermal state thickness value S under different temperature values₁For the cold-state thickness value of the strip steel, the formula (1) of the temperature compensation coefficient and the cold-state thickness of the strip steel can be expressed as follows:

K＝(S₂-S₁)/S₁；

taking a standard thickness sample plate, heating to different temperatures (such as 800 ℃, 900 ℃, 1000 ℃ and the like) under a laboratory condition, measuring the thickness of the standard sample plate by using a ray thickness gauge under the condition of canceling temperature compensation to obtain compensation coefficients under different temperatures, and fitting the compensation coefficients and temperature values into a sextic polynomial curve to obtain an expression formula (2) of the temperature compensation coefficients and the temperature:

K＝1.082e^-18*t⁶-4.054e^-15*t⁵+6e^-12*t⁴-3.065e^-9*t³-1e^-6*t²+0.0015t+0.596

where e is a real number, this formula can also be written as:

K＝1.082*10^-18*t⁶-4.054*10^-15*t⁵+6*10^-12*t⁴-3.065*10^-9*t³-1*10^-6*t²+0.0015t+0.596

and writing the formula (1) and the formula (2) into a temperature compensation program of a control system of the thickness gauge.

Step (2): setting a deviation margin

Setting a temperature deviation amplitude limit value in the width direction in a temperature compensation program of a thickness gauge control system to prevent thickness value calculation errors caused by temperature detection abnormity at a certain point;

in this embodiment, the deviation limiting value is 20 ℃.

And (3): obtaining a digital temperature signal

The pyrometer measures the surface radiation heat energy in the strip steel width direction, and the measurement signal transmits to the temperature measurement system processor through the serial port line, amplifies and A/D conversion processes the measurement temperature value, and transmits the digital quantity temperature signal to the temperature measurement control system through serial ports or Ethernet and other modes.

And (4): temperature compensation

The temperature data of each point of the cross section acquired in the step (3) is accessed into the temperature compensation program of the control system of the thickness gauge in the step (1);

if the temperature in the width direction does not exceed the deviation limit value set in the step (2), calculating the temperature compensation coefficient of each point in the width direction according to the formula (2);

if the temperature in the width direction exceeds the set deviation limiting value in the step (2), substituting the average value of the temperature in the width direction into the formula (2) to calculate the temperature compensation coefficient of the point;

and (5): obtaining the cold thickness value of the strip steel

And (5) substituting the temperature compensation coefficient obtained in the step (4) into the formula (1) to obtain the thickness of the strip steel at each point on the cross section in the cold state, and further obtaining the correct thickness, convexity and wedge value.

In the optimization scheme, the temperature deviation amplitude limits of the same temperature measuring point scanning pyrometer 5 and the single-point altimeter 6 are also set in the step (2), and if the temperature deviation amplitude limit value of the same point exceeds the limit, an alarm prompt is triggered, and high-temperature counting data checking and data substitution switching in the step (4) are manually carried out.

It should be noted that while the invention has been described in detail with respect to specific embodiments thereof, it will be apparent to those skilled in the art that various obvious changes can be made therein without departing from the spirit and scope of the invention.