The negative strip of continuous casting machine playys a vital role while casting quality steel. Negative stip of machine is reffered to the amount of time the mould is in downward direction when the mould speed is greater than casting speed.The basic formula for negative strip time is as follows:
Ns = (Vc-Vm)/Vc
where,
Vc = casting speed (mtr/min)
Vm = mould oscillation speed (cycles/min)Mould osciallation speed can be calculated as follows:
Vm = 2 x f x l
where,
f = frequency at casting speed in cycles/min
l = length of stroke