The multiple Compton backscattering (MCBS) technique has been used to investigate the detection and imaging corrosion under the insulation pipe. An energy source with a mono – energy 0.662MeV of 137Cs has been used. Gamma ray photons have been allowed to be incident vertically on the insulator pipe whose outside diameter, wall and asbestos insulation thickness are (28, 1, 4)cm respectively. The steel pipe has a corrosion defect with a diameter (8) cm. The count rate of scattered γ – photons with scattering angle in the range (130 – 140) degrees has been collected by NaI(Tl) detector with different radius. Assuming the source and detector locations are in the same side from the pipe. Monte Carlo simulation has been written in FORTRAN95 language programming to follow the history of photons.
This study provides the ability of this technique to detect and imaging the corrosion under the insulator pipes. The radius of detector which gives good results for corrosion detection and imaging is 6cm among five different selected radius.