The tension fluctuations between the Enlarging Stand and the Reducing Stand of the rolling mill are mainly caused by four aspects.
1. Rectification of Geometry Data
Due to the inertia of the mechanical system, the tension change speed measured by the ADC sensor is slow during the rectification process of the geometry data on the rolling mill due to the change of geometry parameters such as slab internal stress, slab width, etc. The tension of the small rolling mill is also slowly stretched, and the tension is large.
2. Out-of-roundness of rolls
The most serious problem of tension fluctuations is the out-of-roundness of rolls. The existence of out-of-roundness of rolls will cause unevenness and irregularity of the rolled strip. In particular, the rolling mill in the thin strip production = process is even worse, the strip extends in width, direction occur deviations, and then leads to the tension fluctuations.
3. Vibration of Speed Reducer
The vibration of the speed reducer of transient roll forming also has a direct effect on the fluctuation of the tension. The vibration of the speed reducer can cause the materials to bump and roll forward, resulting in uneven speed and tension.
4. Mechanical Friction and Roll Sticking
The mechanical friction of the Enlarging Stand and the Reducing Stand affects the stability of the tension, and will cause raw material slippage in the case of large tension and then cause tension fluctuations. In addition, when the rolling speed is too slow or too fast, or when foreign matter such as steel scraps and water are mixed in the rolling material, sticking occurs and the tension fluctuates.
In summary, the tension fluctuations between the Enlarging Stand and the Reducing Stand of the rolling mill are mainly caused by the rectification of geometry data, the out-of-roundness of rolls, the vibration of the speed reducer, and the mechanical friction and roll sticking. In order to reduce the tension fluctuations, operators must pay attention to the real-time operation of the entire production process of the rolling mill, optimize various parameters in time, ensure the dynamic balance of the rolls, properly maintain the equipment, and abide by the operation rules.
