If a pipe of diameter of D1 having pressure P1 and length L1 is to be plugged for abandonment and to check the integrity of plug this pipe is to be scaled to a smaller pipe Pipe of Diameter D2 and Length L2 can you please help me finding formulas to calculate the pressure required (P2) in scaled pipe to check plug's integrity, as diameter and length is to be decreased so pressure is also to be changed.