In this case the fallowing equation will solve for the volu me of slug to by pumped in barrels (V1). Density of the fluid in the well measurd in PPg (Ph)is multiplied by the desired length of empty drill pipe (Lp) in feet, and then multiplied by the capacity of the drill pipe (Cdp)articulates in barrels perfoot, The numerator is then divided by the densily of the slug fluid (p1) subtracted by the de nsily of the fluid in the well.