Flying shear / cut to length dividing shear
FUNCTIONAL DESCRIPTION OF FLYING SHEAR
The shear will be located after the finishing mill and before the cooling bed. One no. encoder shall be installed at the motor/pinion stand of the finishing stand. This shall sense the exact RPM of the finishing roll. The mill operator shall decide the length of the bar to be cut, the exact roll dressed and shall feed the data to the MMI (Man Machine Interface).
One no. H.M.D. (Hot Metal Detector) is installed after the finishing mill, which shall see the incoming bar and give signal to the shear. The shear initiates the cut after the time interval T, corrected for the dressed diameter and dip in the motor rpm on load.
V = Velocity of the bar is 3.142 x D x N
D = Dressed roll dia, fed into the MMI
N = Actual motor RPM, data given by the finishing mill encoder. This data is correct
for the dip in the motor rpm on load for improved accuracy.
S = Distance from the HMD to the shear.
T = Time delay for initiating cut = V/S
BASIC SPECIFICATION OF FLYING SHEAR
CONTROL FOR FLYING SHEAR COMPRISES OF :