LSAW steel pipe is a steel pipe whose weld seam is parallel to the longitudinal direction of the steel pipe. Generally divided into metric electric welded steel pipes, electric welded thin-walled pipes, transformer cooling oil pipes, etc. Welded pipes with larger pipe diameters can be produced with narrower billets, and welded pipes with different pipe diameters can be produced under the same billet width, but are comparable Compared with long straight seam pipes, the weld length is increased by 30% and 100% respectively, and the production speed is lower. Next, I want to introduce how to measure the length of a straight seam steel pipe.
According to the different processes of the manufacturer, the length of LSAW steel pipe measurement system has a various of measurement methods, are following types:
1. The basic principle of measuring the length of the grating ruler is: two fixed-length grating rulers are set on the outer side of the LSAW steel pipe, the grating rulers at both ends of the steel pipe are driven by a rodless cylinder, and the length of the LSAW steel pipe is measured by light interference. It has the characteristics of high precision, but the grating ruler is expensive, difficult to maintain, and sensitive to the influence of dust and on-site vibration.
2. Camera length measurement. The camera length measurement is to measure the length of the steel pipe through image processing. A series of equidistant photoelectric switches are installed on one section of the LSAW steel pipe conveying roller, and the light source and camera are added to the other section. According to the position of the image taken by the camera on the screen and the photoelectric switch, the length of the steel pipe can be determined. The feature is that online measurement can be achieved. The length data can be obtained when the steel pipe passes through the measurement area without intervals. The disadvantage is that if there is no special light source, the steel pipe will be interfered by external light. After the special light source is used, the pipe end is chamfered. The rear brightness is high, and the reflection of light is strong, which is easy to cause reading errors.
3. Encoder length measurement, the principle is to install the encoder at the cylinder, use the cylinder to promote the movement of the steel tube on the roller table, and install a series of equidistant photoelectric switches on the other side, when the steel tube is hit by the tube end photoelectric switch driven by the cylinder , The stroke of the cylinder can be converted from the recorded encoder readings to calculate the length of the steel pipe. Its characteristic is that the steel pipe needs to be raised when measuring the length. In addition, there are some errors in the photoelectric switch detection, which may require sufficient measurement.
4. The improved encoder length measurement method is an indirect measurement method. By measuring the distance between the two ends of the steel pipe and the respective reference points, the length of the steel pipe can be measured indirectly. This measurement method overcomes the complex environment of the production site, the large volume of the steel pipe, and the measurement The mechanism cannot cross the support platform under the steel pipe, and is easy to operate. The measurement accuracy is less than ±10 mm, and the repeatability is ≤5mm.
The above is to share with you the relevant content of the method of measuring the length of the LSAW steel pipe. I hope that through the above content, everyone can have a better understanding of the method of measuring the length of the LSAW steel pipe.
