?? KT(??-????) = (E x d4)/[(3667 x D x N) + (389 x (a1 + a2))] KT(??-?????) = (E x d4)/(3667 x D x N) M (????) = KT x Q (Q=??? ??) T (???? ??? ??) = (K x 32 X M)/(3.14 x d3) K (??????)= (4 x C2 + (C-1))/4 x C x (C +1)) F (??? ?? ???? ???) = (Q x D)/(360 x N) Ds (??? ??) = 0.9 x (D-d-F)