There will be many problems in the production of ERW steel pipes. The following will mainly talk about some problems of diameter machine analysis. In contrast, the mill with fixed minimum speed has relatively simple process, and there are some types of sizing machines in common use.


1. Dimensional scratches mainly attack the cross section of the pipeline on both sides of the horizontal and vertical axes, and the multi-layers roll through the edges by horizontal and vertical rolling. Especially after edge R circle sharpening, the following problems may cause harm once they occur.


2. Drill pipe doubts are rare, and the opportunity for comparison is usually the occurrence of thin-walled pipes, which is due to poor primary rigid thin-walled pipes and simple rolling bite because of thin-walled pipes. Therefore, it is assumed that the following problems will form drill pipes in the occurrence of accidents.


3. Tubes are not circular - Circular is usually elliptical, circular and ribbed gourd-shaped three kinds.


4. The basic principle of straightening is to use leverage to make the tube axial deformation occur again and then straighten it.