Development of Coded Excitation UT and Microwave Inspection for Reinforced Thermosetting Resin Pipes
TWI Industrial Member Report 1216-2026
By Owen Rees-Lloyd and Sam Hurrell
Industrial Need
Fibre-reinforced pipes have been gaining popularity in the oil and gas industry due to their strength to weight ratio and their corrosion resistant properties. X-ray has historically been the inspection method of choice for this piping, however there is a need to shift to inspect via other methods, to reduce costs and eliminate the safety risks associated with ionising radiation. An obvious replacement inspection method is Ultrasonic Testing (UT). However, there is a need to further develop the capability of ultrasonic testing of fibre-reinforced pipes and overcome the limitation of the material’s highly attenuating structure. Coded excitation is a technique that has been proven to dramatically increase the signal to noise ratio (SNR) with low energy systems.
Key Findings
- Coded excitation was successfully implemented via a TPAC Pioneer pulser/receiver system and TWI Crystal™
- No significant increase in SNR between coded excitation using full matrix capture data acquisition and total focussing method reconstruction (FMC/TFM) and FMC/TFM without coded signals
- Microwave inspection was capable of detecting wall thinning within 0.2mm change, however it was incapable of detecting flat bottomed holes present in the samples tested.
Impact
Although coded excitation could not increase the SNR seen when using FMC/TFM on RTR piping, its implementation within TWI software allows it to be used in other industrial applications. The use of microwave on RTR piping (as an alternative NDT method) has resulted in a novel way of analysing collected microwave data.