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

• Frame: Steel fabricated by M.I.G. welding duly stress relieved.
  
• Pinions/Gears: EN353/354 integral case carburized and heat treated to 60+-2 HRC.
• Blade Shafts: EN9 forged and heat treated from 260 to 280 BHN
• Lubrication: the frame is provided with spray lines to the gears and the lubrication lines to bearings, including pumping unit complete.

CONTROL FOR FLYING SHEAR COMPRISES OF :

• DC motor for the Rotary dividing shear
• Four quadrant Digital drive rated for 725 Amps for the DC motor
• Encoders - Two nos.
• Proximity switch for positioning - One no.
• Hot metal detector - One no.
• Control desk facility for Test, Speed variation commands and digital speed indicator.

Crank Driven Flying Shear

Flying Shear Machine