1. Improper adjustment of correction frame
Bending phenomenon: Rigid steel tube bends from finishing element to one direction.


2. Uneven coil thickness
Bending phenomenon: The bending phenomenon of steel tube is serious, and the bending direction of steel tube is not one direction.


3. Temperature non-uniformity on the upper and lower surfaces of steel pipes
Bending phenomenon: The steel pipe in the production after cutting is straight, but it will bend when it is cooled on the finishing mill stand. The overall bending direction of the steel pipe is the same.


4. Insufficient size
Bending phenomenon: Before hydrostatic pressure test, the steel tube is straight, but after hydrostatic pressure test, the bending phenomenon occurs, and the bending direction is fixed.