introduction
Wire rolling is developed along high speeds and in two consecutive directions. At the same time as the modern wire rod mill was built, the existing wire rod mills continued to tap into their potential and transform and innovate. In recent decades, wire rod rolling technology The rolling mill has been driven separately, the roll has been replaced quickly and the tension control system has been installed. The AGC automatic control system enables high-pressure sizing control and so on. The dimensional tolerance of wire products and the mechanical properties of the products have been greatly improved. The quality of production and control, accurate measurement of the wire size is also very important, this article describes the automatic measurement of wire rod on-line caliper.
1, special requirements for measuring rod diameter
With the continuous improvement of bar and wire rolling technology, the rolling speed is faster and faster. The maximum rolling speed of bar has reached 18 to 36 m/s, and the high line rolling speed has reached 120 m/s. At the same time, the quality of rod and wire products has been improved. The control requirements are also getting higher and higher, among which the requirements for measuring the diameter of rolled products are summarized as follows:
(1) It can meet the rolling speed and can perform high-precision testing in the case of jitter.
(2) Better discrimination of ear and other cross-sectional shape defects.
(3) It can record in detail the shape change of the 'head' and 'tail' of more than ten meters in order to facilitate the analysis of rolling production.
(4) It can record the amount of fluctuation of the same rolling stock before and after each direction to understand the situation of roll wear and pressure.
(5) It is necessary to have an enlarged deviation map of the outside diameters in all directions to facilitate monitoring of the roll gap surface and the whirling condition of the rolled material.
2, diameter measuring principle
The on-line diameter measuring instrument adopts the principle of optical measurement. A parallel beam of light is formed by the optical system. An electronic image is formed on the line array CCD by the receiving lens. The image size of the object corresponding to the parallel beam is determined by image processing.
The advantage of this measurement method is that there are no mechanical moving parts, there is no error caused by wear; the shadow of the object can be captured at the same time, so the lateral jitter error is much smaller than the laser scanning method. The shooting speed is fast and the measurement frequency is high.
In order to detect the deviation in all directions, the online diameter measuring instrument uses the eight-axis measurement method to measure the outside diameter of the steel under test. It can also use the four-axis, three-axis. , Double-axis caliper instrument, can also detect ellipticity information, according to the required detection requirements to select the appropriate online diameter measuring instrument.
3, the solution
(1) Rolling speed
The rolling speed of steel is very fast, the online diameter measuring instrument also needs to adapt to its speed, and carries out high-speed measurement. At present, the measuring frequency of the online diameter measuring instrument can reach 500Hz. According to the measurement needs, it can also be customized to 1000Hz. High-speed measurement can be realized. The measurement of the rolling stock does not affect the measurement at all.
(2) Detecting basic defects
For the detection of basic defects, the online diameter measuring instrument can also be well completed. At present, in the course of use, common defects of the steel can be detected such as: 'ears', 'wrong roll', etc., and the detection effect is good.
(3) Record head and tail changes
The online diameter measuring instrument has a storage function and can store the measurement data for a long time of more than one year. Not only the change of the recording head and tail, but also the measured data of the rolled material of the entire measured object are recorded, and the measurement data can also be tabled. Form export.
(4) Fluctuations in all directions
Of course, the online diameter measuring instrument also has an analysis function. It can display the fluctuation maps in all directions, and can see the trend of the entire outer diameter of rolling stock. When the mouse points to the corresponding time position (left click), a The vertical cursor can observe the corresponding diameter condition. In addition to displaying the fluctuating map, the diameter measuring instrument can also display the defect map in all directions. The overshoot type of the eight-way measurement value can be observed, such as overshoot, undershoot , ellipticity and so on.
(5) Magnification of the deviation of the outside diameter in each direction
The online diameter measuring instrument is an eight-direction diameter measuring instrument, which means that it can measure the dimension of the wire diameter in eight directions. The same cross section can be detected. The distance between each probe is 22.5°, which can be measured in all directions. The wire size in each direction can be displayed in detail. The cross-section can show deviations in all directions and is very intuitive.
Conclusion
The online diameter measuring instrument is a precision measuring device specially designed for measuring the outer diameter of a wire bar. It can not only detect the outer diameter of a round rolling stock, but also can be used for the inner diameter of rebar, cross ribs, longitudinal ribs, cross sections. Area measurement. Easy to use and easy to operate, providing operators with professional measurement data.
This article consists of Baoding Lanpeng Measurement & Control Technology Co., Ltd. write
