Causes of Piling up of Steel

The phenomenon of piling up of steel will occur during the rough and medium rolling of wire rod, which can be divided into steel piling at the head, middle and tail of rolling piece. Specific reasons and solutions are as follows:

1. Steel stacking at the head of the rolling piece

(1) The friction force of the rolling groove is too small after changing roller and groove, which causes the head of the rolling piece to slip;

(2) The head of the rolled piece is warped after it comes out of the frame so that it can not smoothly bite into the downstream rack or the top guide position of the head;

(3) There are foreign matters in the rolling groove or guide groove;

(4) The billet is seriously off the square and cannot enter the rolling mill or take out the outlet pipe;

(5) Eject the guide or winding roller from the blank split.

Solutions:

(1) Increase the groove friction force when changing the roller and groove, polish the groove with a grinder or adopt spot welding method, and close the cooling water of the roller until it is completely bitten in;

(2) Check whether the guide guard base is loose, whether the rolling line is aligned, and replace the old guide guard in time.

(3) in the rolling process, clean the oxide scale in time;

4) In the rolling process, the unqualified billets shall be removed in time. In the case of splitting, the emergency stop shall be made as soon as possible to reduce the time for scrap treatment.

2. Steel stacking in the middle and tail of the rolling piece

(1) Steel piling due to improper roll gap setting and improper rolling piece size;

(2) The defects of billets, such as inclusions and bubbles, break during rolling causing steel piling;

(3) The rolling mill is in the state of stacking rolling due to improper design of rolling speed. When the front half of the rolled piece is close to the front rolling machine to maintain micro tension rolling, and when the tail of the rolled piece leaves the front rolling mill, the tension at this place suddenly loses, resulting in stacking at this stand;

(4) Steel piling caused by sudden speed up or speed down of frame motor;

(5) Steel piling is caused by sudden fracture of roll or serious damage of guide guard in previous passes.

Solutions:

(1) after changing the roll and groove, set the groove bottom accurately, measure the roll diameter and speed correctly, and reduce the speed error;

(2) Strengthen the inspection of unqualified blank;

(3) Correctly adjust the tension between frames;

(4) Check the electrical equipment and replace the damaged electrical components;

(5) check the cooling water quantity of the roll and adjust the steel temperature, prohibit rolling low-temperature steel and blackhead steel.