There are several methods of quenching the OCTG pipes
, dipping, axial injection, laminar jet and laminar jet combined with axial injection. It will form the centrifugal force when quenching OCTG pipes and the centrifugal force will cause the deformation on pipes, which has serious influence on the quality and application of pipes.
Therefore, it’s significant to have distortion control during quenching OCTG pipes.
1. Apply the quenching step by step.
Since the quenching water is flowing from one end to other end, therefore, the cooling rate is different in the two ends of pipes, which will make the pipes to be bent. Manufacturers can water the outer surface and then the inner, so that can prevent pipes from bending. Prolong the tine about 2 to 10 seconds for inner cooling.
2. Reduce the hanging length of pipes in the rotating wheel.
Through reasonable length control, make the hanging length with 600mm, which can reduce centrifugal force during quenching and decrease the bending degree of OCTG pipes.
3.Control the speed of rotating wheels reasonably.
4.Control the center of quenching rotating wheels reasonably.
The deviation of rotating wheels has a great impact on the bending degree of pipes. Tests show that, the control of rotating wheel center should be controlled with 5mm.
5. Control the amount of quenching water.
The amount and speed of quenching water are also important factors to cause the distortion of OCTG pipes. For instance, the OCTG pipe with 127mm outer diameter and 10mm wall thickness, the speed of quenching water should control in 1300 to 2000 cubic meters per hour for outer side and 200 to 100 cubic meters per hour for inner side.