At present, the more common length of spiral steel pipe is 12 meters / branch, but there are many other lengths, in order to more accurately know the length of spiral steel pipe, the following are several common methods.
1, camera length measurement.
Camera length measurement is the use of image processing to achieve the length of steel pipe measurement, the principle is to install a series of equal distance photoelectric switch on a section of the steel pipe conveyor roller conveyor, add a light source and camera on another section. When the steel pipe passes through this area, the length of the steel pipe can be determined according to the position of a photoelectric switch on the screen through the image taken by the camera.
The feature is that online measurement can be realized, and the length data can be obtained when the steel pipe passes through the length measurement area without interval. The disadvantage is that: if you do not use ad hoc light source irradiation, the steel pipe will be disturbed by external light, and the use of ad hoc light source due to the high brightness of the tube end after the chamfering and the reflection of light is very strong, easy to cause reading errors.
Spiral steel pipe length several common measurement methods
2, measuring length of the scale
The basic principle is: the outside of the two ends of the steel pipe are set up two fixed length of the scale, the use of rodless cylinder drive the scale near the ends of the steel pipe, the use of light interference phenomenon to achieve the measurement of the length of the steel pipe.
The characteristic is high accuracy. However, the scale is expensive and difficult to maintain, sensitive to the impact of dust and site vibration.
3, encoder length measurement
The principle is to install the encoder at the cylinder, using the cylinder to push the steel pipe in the roller conveyor movement, installed on the other side of a series of equal distance photoelectric switch, when the steel pipe is pushed by the cylinder end touches the photoelectric switch, from the recorded encoder readings, converted to the cylinder stroke, so that the length of the steel pipe can be calculated.
The characteristic is that the steel tube needs to be lifted when measuring the length. In addition, the photoelectric switch detection also has a certain error, may need to be fully measured.
4、Improved encoder length measurement
This method is an indirect measurement method, by measuring the distance between the two ends of the steel pipe and the respective reference point, the length of the steel pipe is measured indirectly. At each end of the steel pipe set up a length measurement trolley, the initial position is zero, the spacing is L. Then move the length of the editor to the respective pipe end of the walking distance (L2, L3), L – L2 – L3, that is, the length of the steel pipe. This measurement method to overcome the huge size of the steel pipe, the production site environment is complex, the measurement mechanism can not cross the lower steel pipe support bench and other difficulties. This method is easy to operate, and the measurement accuracy is within ±10mm, with a repeatability of ≤5mm.