While paying attention to the advantages of short stress line mill, we can not ignore the problems_ Causes of two kinds of marks on the surface of cold rolled ribbed steel bars

[I. while paying attention to the advantages of short stress line cold rolling mill, the existence of problems cannot be ignored]
There are many types of cold rolling mills, but there are still some special cold rolling mill types that are more concerned, such as short stress line cold rolling mill. Compared with ordinary cold rolling mill, it has more advantages and many problems to be solved. The following detailed instructions on this should be helpful to everyone.
As the stress loop of the short stress line mill is greatly shortened, the stiffness of the mill will be improved and the accuracy of rolled products will be improved. In addition, the structural design of the short stress line mill is relatively compact, which greatly reduces the difficulty of assembly and parts replacement.
The above is the performance of advantages, but the focus is still on the problems to be solved, which is the key to the progress of cold rolling mill. Because there are usually more than two sets of roll groups in the short stress line mill, the cost of replacing the roll is also relatively high. In addition, due to the large stress on the compression nut, it is easy to cause damage. In this case, other matching parts must be replaced. If these two problems can be solved, the application of short stress line mill will be further expanded.
[II. Causes of two kinds of marks on the surface of cold rolled ribbed reinforcement]
The cold-rolled ribbed steel bar has just been introduced from the cold rolling plant. Roll marks and scratches were found when checking the surface quality. what is it? In order to find out the reason, we specially consulted professional manufacturers and obtained the following results:
This paper mainly analyzes the causes of indentation of cold-rolled ribbed bars in two cases. If periodic indentation occurs on the surface of ribbed reinforcement, it may be caused by too little preload or roll meat falling during large-scale rotation of the cold cold rolling mill. In this case, it is necessary to repair or replace the work roll, and give a certain rolling pressure or use bending roll when the cold cold rolling mill is idling, so as to avoid local damage to the roll, find local damage to the intermediate roll and backup roll, and reduce the indentation depth on the roll surface.
If periodic convex marks appear on the surface of ribbed reinforcement, it is mainly caused by cracks or spalling on the surface of work roll. Before replacing a new work roll, strictly check the surface quality of the roll to prevent the roll without wear and crack from being put into use. Ensure that the process lubrication of each frame is good, and the temperature, concentration and pressure of rolling fluid are kept within the normal range.