Minimum Tension Control In Rolling Mill

A non linear state space process model which represents the mill dynamics has been developed and a control scheme is proposed which incorporates an extended kalman filter for estimation of bar tension and optimal state feedback to provide appropriate control action.

Minimum tension control in rolling mill.

During production the loop and tension control automatically adjust the r factor ensuring minimum material stress between the stands. F t t r t m 3 where t r is the output torque of motor in tension free rolling. Control target of minimum tension control the definition is as follows. Roundness is defined as the difference between maximum diameter and minimum diameter.

The aim of the tension control in the mill is to control the stands speed and to maintain the stable and low tension conditions. Looper and tension control shown in fig. This parameter directly related to rolling fundamentals simplifies the setup and operator control. 2 is important in hot strip mills because they affect both the dimensional quality and the mass flow of a strip the high strip tension between stands induces width shrinkage thickness reduction and moreover can produce an edge wave on a strip.

Rolling force decreases with the increase of interstand tension while the tension torque increases with the increase of back tension and decreases with the increase of front tension. Changing roll velocity stabilizes the interstand tension. Interstand tension should be maintained at acceptable levels. Cobble grooves mill speed motor roll gap rolling mill rolls tension control yield.

Tension control is one of the most important process parameters in tandem cold mill tcm. δt k t m k t r f t 4. Tolerance is the allowable difference in maximum minimum dimensions with respect to nominal dimensions. The error of motor torque in the k th sample is as follows.