How to control the precision of seamless steel pipe?

Precision seamless steel pipe has higher precision, so it has very good comprehensive performance. After heat treatment, precision steel pipe can be used in many different working environments.

1. Billet heating
Heating should be uniform, and rapid rise and fall of temperature is forbidden. The temperature rise and fall should be steady and slow every time, and the maximum temperature rise and fall should not exceed 30 ℃.
2. Centering roller
Determine whether the centering roll is installed in place, adjust the center, opening angle and opening size of relevant core holding roll. The center of core holding roll should be on the rolling line.
3. Rolling center line
Ensure that the center line of piercing mill is consistent with the center line of piercing trolley, avoid "up rolling" or "down rolling", so as to keep the force uniform during piercing.

4. Rolling tools
The worn plug, guide plate, roll and other rolling tools should be replaced in time.
5. Installation of rolling tools
The center of roll distance and guide distance must be on the rolling line. Ensure that the center line of guide distance and roll distance is on the center line of piercing rolling, that is, the upper and lower roll distances are equal, and the left and right guide distances are equal.
6. Piercing ejector
Generally, the outer diameter of the piercing ejector is 0 Φ 108mm- Φ 114mm, seamless steel pipe is required to be ≥ 25mm, and seamless steel pipe is uniform thick wall pipe.
7. Mandrel of rolling mill
The mandrel should be made of seamless steel tube and thick wall tube. For smaller mandrel, solid blank can be used instead. The uniform thick wall tube and solid blank of seamless steel tube can greatly reduce the probability of mandrel bending deformation and effectively improve the accuracy of seamless steel tube.