TPT September 2008

4.4 Tube tracking control (TTC) Tracking of the tube is achieved in different ways: based on the theoretical calculation the position of the tube or tube sections is determined with the HMD signal in front of the mill and the speed measurement at the entry side. Additional HMDs are installed between certain stands in the block. With each HMD signal the track position is corrected to the actual position. Another correction of the tracked position can be carried out with a load detection of the motors. However, this detection is only possible for mills with individually driven stands. 4.5 Neutral place correction (NPC) The exit speed of the stretch reducing block can be kept almost constant by using the integrated NPC function. There is always a ‘theoretical’ position in the block, where the circumferential speed of the roll is

 Figure 5 : Main screen Tumicon inspect

equal to the tube speed. This position is called ‘neutral place’. The NPC functions always keep the speed for the neutral place constant. By shifting the neutral place to a different position for the different rolling phases of the tube – such as entering the block, stationary situation, exiting the block – the exit speed can be kept constant. Different neutral places can be selected in the Tumicon Inspect and can be changed during the rolling of the tube. 4.6 Tumicon Inspect The Inspect system is a visualization tool for the technological functions of the TecBox. Inspect loads the requested values from

In case of a new Kocks SRB or stretch reducing mills with individually driven stands, a minimum number of stands are used for the tension control to influence the wall thickness over a minimum length of the tube. The parameters are loaded from the Tumicon database; the user can restore individual corrections in the database. 4.3 Heavy end control (HEC) Due to the applied tension, heavy ends are created at the head and tail of the tube. The HEC of the Tumicon TecBox minimizes this effect and leads to a higher output of the mill.

 Figure 6 : Tumicon remote control

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S eptember 2008

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