Do you know how to solve the issue of screws automatically loosening in the rolling mill?

During the normal operation of the rolling mill, abnormal work of its combined equipment, such as the roughing mill and the strip coarse rolling mill, can cause the opening and change of the roll gap in the rolling mill, thereby affecting the accuracy of the rolled piece and resulting in uneven thickness of the rolled piece. The usual reason for this situation is that, under medium pressure in the rolling mill, the screw pitch is too large, and the helix angle is greater than or close to the self-locking angle of the thread. The self-locking property of the rust removal machine's pressing down mechanism is easily damaged during the rolling process.

The structure of the screw head is mainly divided into three parts: the head, the tail, and the thread body. Under medium pressure, the head can come into contact with the bearing seat of the roll by a spherical pad or thrust bearing, bearing the rolling force from the roll neck and the balancing force from the upper roll. The thread body generally uses sawtooth or trapezoidal threads, mostly single-threaded, to increase the self-locking ability. Understanding the structure allows us to better solve the problem of screws automatically loosening.

Common solutions include: increasing the friction resistance distance between threads, appropriately increasing the diameter of the pressing thread, reducing the thread helix angle to increase self-locking ability. However, an excessively large diameter causes the size of the rolling mill to be too large. Increase the diameter of the pressing thread spherical pad (d3) and the opening diameter (d4) to increase the friction torque. In addition, use appropriate lubricants and adopt two systems that can operate independently and in conjunction to meet the requirements of adjusting the parallelism of the rolls.