We have 42" crude oil pipe line which is constructed 20 yrs before. Now they are replacing launcher, not receiver. there is a requirement of leak detection system based on leak sensitivity study. if it is pressure method, how many sensors required? only launcher there is pressure, temp, flow transmitter available. receiver side no instruments. since pipe line is 20 yrs old, is there any possibility to install PT, TT and FT since there is no tapping point?