RF transmissions

am working on modes of propagating low voltage rf signals using a long Al/Zinc pipe (originally used for fluid transmissns) as a medium.

Can anybody help me.

Thankx

Need the RF frequency and the pipe size.

tanx carl

am actually workin on a model of detecting a break in d RF transmission hence the 10m,1.5 ft diameter pipe with about 2inch thickness
all i need is enof frequency to guarantee signal strenght throughout the pipe lenght so a significant signal loss will be easilly detected.