[1A1] Ultrasonic NDT for non-intrusive inspection of pressure vessels and pipework at elevated temperatures
S F Burch and H R Peramatzis
ESR Technology, UK
The reduction of down-time related costs and the safety benefits make Non-Intrusive Inspection (NII) an attractive alternative to Internal Visual Inspection (IVI) for pressure vessels. The HOIS joint industry project has developed publicly available guidance for NII, HOIS-RP-103, which clarifies the requirements planning, implementation and evaluation of NII. The document also provides some guidance on techniques that are aligned to the performance requirements for NII. This does not, however, include recommendations for in-service inspection of components at elevated temperatures.
To address this, a project in HOIS has been focussing on NII of components at temperatures up to 250°C (at the upper end of typical upstream applications) with an emphasis on scanning ultrasonic systems used for methods such as corrosion mapping, TOFD and angled-beam pulse-echo. Trials of different systems, which require probes to be in contact with the hot surface much longer than those used for spot thickness measurements, have been performed on ex-service and manufactured test samples.
This paper will highlight the technical challenges associated with ultrasonic scanning systems at elevated temperatures. The results of the trial programme will lead to the development of recommendations for inspection to support NII at elevated temperatures.
To address this, a project in HOIS has been focussing on NII of components at temperatures up to 250°C (at the upper end of typical upstream applications) with an emphasis on scanning ultrasonic systems used for methods such as corrosion mapping, TOFD and angled-beam pulse-echo. Trials of different systems, which require probes to be in contact with the hot surface much longer than those used for spot thickness measurements, have been performed on ex-service and manufactured test samples.
This paper will highlight the technical challenges associated with ultrasonic scanning systems at elevated temperatures. The results of the trial programme will lead to the development of recommendations for inspection to support NII at elevated temperatures.
