Abstract
Pulse echo measurements are used to investigate the conditions on the outside of an oil or gas pipe by sendingultrasound pulses onto the pipe wall from inside the pipe that reverberate within the pipe wall. A range ofdifferent algorithms are used today to analyse this data and derive pipe-wall thickness and impedance ofthe material behind the pipe, with the aim of determining the bonding of the material. To be able to developcurrent algorithms further it is crucial to understand currently used algorithms and their advantages anddisadvantages. The downside with using logging data from real boreholes is that no ground truth exists,making it difficult to evaluate the accuracy of the different algorithms. Therefore, we built a databaseof numerically generated data. This database allows us to investigate the effects of variations like casingdiameter, thickness, bonding, and eccentering on the derived casing thickness and outer- material impedanceusing different analysis algorithms. Here, we use three of the most used algorithms and discuss comparisonsof results gained from the analysis of the simulated data in the case of tool eccentering and existence ofa fluid-filled annulus gap between pipe and cement on the outside showing the value of simulated data toimprove and understand estimates of pipe thickness and outer-material impedance.