Precautions for wall thickness calculation of 15CrMo boiler oil cracking steel pipes. The method for calculating wall thickness in the production of 15CrMo boiler oil cracking steel pipes is: first, calculate the roller speed of each pass according to the given main and auxiliary motor speeds (Formula 1), and then set the tension coefficient of each pass. Since the hole size is certain, after setting the tension coefficient of each pass, the working diameter of the roller of each pass and the wall thickness of the 15CrMo boiler oil cracking steel pipe after each pass can be calculated according to formulas (2, 3). Based on this, the elongation coefficient and outlet speed of each pass of the 15CrMo boiler oil cracking steel pipe can be calculated (Formula 4), and then the number of roller revolutions of each pass can be calculated according to the outlet speed and rolling diameter (Formula 5). If the set tension coefficient is not appropriate, then there will be a difference between the calculated roller revolutions and the roller revolutions converted from the main and auxiliary motor revolutions. At this time, the sum of the absolute values of the difference in the number of revolutions of each pass can be used as the basis for whether to terminate the calculation. If this value is small enough, the calculation can be terminated.
After the hole size is determined, the outer diameter size of the finished 15CrMo boiler petroleum cracking steel pipe is also determined. When the spindle motor speed is given, the number of roller revolutions of each pass is determined accordingly, and the tension of each pass is determined accordingly. However, the tension coefficient of each pass needs to be calculated.
The tension coefficient of the first frame entrance and the last frame exit is set to 0
Two factors should be considered when setting the tension of the intermediate frame:
1) The number of roller revolutions after setting the tension should be consistent with the actual number of revolutions
2) After setting the tension coefficient, the neutral angle of the next frame should also be calculated. If the neutral angle of the next frame is less than 0, it means that the set tension coefficient is too large. At this time, the tension coefficient should be appropriately reduced.
3) Since there are many rolling mills for tension reduction, there are many unknown numbers to be calculated. If you want to optimize the calculation, you need to program it.
4) The calculation accuracy depends on the requirements. Generally, the higher the calculation accuracy, the longer the program will run.
In the actual production of 15CrMo boiler petroleum cracking steel pipes, you also need to verify your theoretical algorithm through card rolling experiments, because many intermediate parameters need to be processed in advance.
Post time: May-31-2024