High temperature ultrasonic measurements of plant and components for defect detection and monitoring

Lead Research Organisation: University of Warwick
Department Name: Physics

Abstract

There are many instances where components and plant operate at elevated temperatures such as turbines, high temperature processing pipework, power generation boilers and reactors. Currently, most non-destructive testing (NDT) is carried out at lower or ambient temperature, necessitating at least partial shut-down of the process. Planned outage of plant is costly but the cost of unplanned outage due to catastrophic failure can run to millions of pounds, and can have extremely serious consequences for the safety of personnel and the public. In addition, some plant contains areas that are extremely difficult to access even during an outage meaning that the only viable approach is to use permanently installed monitoring. We propose devices and concepts to enable high temperature monitoring and inspection where it is currently impossible. This is stimulated not only by the industrial imperative, but also by major advances in knowledge and understanding of high temperature piezoelectric materials, in thick film and thin film form, operating at temperatures up to 800C. The attraction in developing high temperature sensors from these materials is that they can be robust, inexpensive and permanently installed on plant. In a novel hybrid system concept, not previously applied to high temperature inspection, we will combine these with improved non-contact ultrasonic generation techniques.

Publications

10 25 50
 
Description There are many instances where components and plant operate at elevated temperatures such as turbines, high temperature processing pipework, power generation boilers and reactors. Currently, most non-destructive testing (NDT) is carried out at lower or ambient temperature, necessitating at least partial shut-down of the process. Planned outage of plant is costly but the cost of unplanned outage due to catastrophic failure can run to millions of pounds, and can have extremely serious consequences for the safety of personnel and the public. In addition, some plant contains areas that are extremely difficult to access even during an outage meaning that the only viable approach is to use permanently installed monitoring.

We developed three key strands of research in this project to address some of the challenges experienced for high temperature ultrasonic transduction.

1) The preparation of high temperature piezoelectric material (Bismuth Titanate) by a true Sol-Gel method was developed and demonstrated, leading to the development of thick film materials that could be screen printed onto flexible foils of stainless steel.

2) The development of high temperature electromagnetic acoustic transducers (EMATs) that have been demonstrated operating in a true send-receive mode at temperatures in excess of 900C on steel.

3) We successfully demonstrated the combination of non-contact ultrasonic generators (EMATs and pulsed lasers) with other high temperature piezoelectric transducers such as vacuum deposited AlNi thin film materials, for the generation and detection of ultrasonic guided waves.



In developing these transduction methods we have extended the range of currently available high temperature ultrasonic probes, and characterised the degradation performance of a Sol-Gel prepared high temperature piezoelectric material. We did not have the opportunity of testing these probes in situ, but undertook extensive lab based demonstrations on representative samples at representative temperatures. One of the major challenges that we faced relates to bonding the piezoelectric transducers to steel samples in such a way that a robust bond is formed that is capable of being cycled up to temperatures of 400C.
Exploitation Route The method has been duplicated and referenced by other researchers.
Sectors Aerospace

Defence and Marine

Manufacturing

including Industrial Biotechology

Other

 
Description Published findings for new high temperature NDT measurements using ultrasound.
First Year Of Impact 2014
Sector Aerospace, Defence and Marine,Manufacturing, including Industrial Biotechology,Other
Impact Types Societal

Economic

 
Description BP British Petroleum 
Organisation BP (British Petroleum)
Country United Kingdom 
Sector Private 
PI Contribution RCNDE industrial support
Start Year 2009
 
Description RWE nPower 
Organisation RWE AG
Department RWE nPower
Country United Kingdom 
Sector Private 
PI Contribution RCNDE industrial support
Start Year 2009
 
Description Shell Global Solutions International 
Organisation Shell Global Solutions International BV
Country Netherlands 
Sector Private 
PI Contribution RCNDE support funding
Start Year 2009
 
Description Tenaris 
Organisation Tenaris SA
Country Luxembourg 
Sector Private 
PI Contribution RCNDE industrial support
Start Year 2009