Materials Engineering: Fully Funded Swansea University and UKOPA PhD Scholarship: Fatigue performance of dented pipes (RS620)

Funding providers: Swansea University's Faculty of Science and Engineering, and UKOPA

Subject areas: Materials Science & Engineering

Project start date: 

• 1 October 2024 (Enrolment open from mid-September)

Supervisors:

• Dr Elizabeth Sackett (e.sackett@swansea.ac.uk)
• Tim Rudd (Industrial Supervision)

Aligned programme of study: PhD in Materials Engineering

Mode of study: Full-time 

Project description: 

UKOPA (the United Kingdom Onshore Pipeline Operators’ Association) members operate a network of more than 27,000 km onshore pipeline. UKOPA is the authoritative industry body behind this essential part of energy infrastructure. Pipelines provide the safest and most energy efficient means of transporting a range of hazardous fluids, and pipeline operators are constantly working to improve safety and protect the environment. Since UKOPA was established in 1996, it has brought operators together and helped them engage more effectively with each other, as well as with regulators and other key stakeholders. As the UK prepares for the energy transition a number of these legacy pipelines may be converted to Hydrogen service or to CO2 pipelines. As such, it is vitally important that they remain available for use.

The pipelines that form the network date from many different periods, with significant amounts constructed pre-1970’s. As such, these are now ageing assets so it is vital to ensure they remain safe to operate. To do this we need to understand fully the mechanical properties of the pipelines. Due to the age of the network, a lot of the older pipeline sections will have been constructed to less stringent standards/procedures than in place today, and will have had less Inspection & Testing during construction.

Pipelines are constructed of individual segments (spools) joined together in the field. The circumferential joints are known as Girth welds. Where pipe has been rolled and joined to form the pipe, the longitudinal joint is known as a Seam Weld. During operation, the pipeline can become damaged or dented. Dents most commonly occur due to impact damage after construction, but can sometimes become dented due to poor construction practises (such as laying them on rocks). Dented pipelines can suffer from local work hardening in this area, along with the presence of stress concentration factors. These can dramatically reduce the fatigue life vs. un-dented pipe sections.

The fatigue life of un-dented pipe segments is well understood, and the applicability of current S-N curves to historical pipelines has previously investigated by UKOPA and Swansea University. However, there is currently a lack of research and experience on how the presence of dents effects the fatigue life of vintage welds. This project aims to better understand the mechanical properties and fatigue performance of vintage Girth Welds and Seam Welds in pre-stressed pipe sections in order to model behaviour in dented sections and better inform remaining life assessments.

This research will make use of a number of historical samples to enable UKOPA to evaluate the fatigue performance of pre-stressed pipe sections. It will compare and contrast the results with those obtained from modern pipe sections, constructed to the standards in place today. The project may include an evaluation of the material properties of vintage pipe sections after being stressed. Assessments of material composition will be made, and fatigue testing will be performed on samples to determine if the current BS-7608 fatigue curves are applicable for use with historical pipe sections that have seen service for extended time.

Key assessments will be:

1. The fatigue performance of historic girth welds subject to dent strains equivalent to a 2%, 4% and 6% OD dent depth, and 6% strain, to investigate the impact of dents on historic girth weld performance.
2. The fatigue performance of current standard girth welds subject to dent strains equivalent to a 2%, 4% and 6% OD dent depth, and 6% strain, to investigate the impact of dents on girth weld performance.
3. Inspection of weld quality and examination of metallurgical and mechanical properties of historic seam weld samples (will need to specify seam weld type).
4. The fatigue performance of current standard seam welds subject to dent strains equivalent to a 2%, 4% and 6% OD dent depth, and 6% strain, to investigate the impact of dents on seam weld performance (will need to specify seam weld type).

These assessments will feed into the remaining life evaluations used to determine if pipelines can continue to be operated into the future or re-purposed as part of the energy transition.

The desired candidate will have a BEng or higher in Materials Engineering, Aerospace Engineering or Mechanical Engineering (or related disciplines) or relevant work experience in steel fabrication, welding or NDE.

The project will be based out of Swansea university, but the successful student will have the opportunity to travel to attend UKOPA meetings to present results (usually held near Derby) or to visit industrial sites for meetings or to gain site experience. There may also be opportunities to present the research at industrial conferences within the UK or Europe.

Candidates must hold a UK bachelor’s degree with a minimum of Upper Second Class honours or overseas bachelor’s degree deemed equivalent to UK honours (by UK ECCTIS) and achieved a grade equivalent to UK Upper Second Class honours in Engineering or similar relevant science discipline. If you are eligible to apply for the scholarship but do not hold a UK degree, you can check our comparison entry requirements (see country specific qualifications). Please note that you may need to provide evidence of your English Language proficiency. 

English Language: IELTS 6.5 Overall (with no individual component below 5.5) or Swansea University recognised equivalent. Full details of our English Language policy, including certificate time validity, can be found here. 

This scholarship is open to candidates of any nationality.

International Fee Eligible Students:

Swansea University is pleased to offer the Swansea University International Postgraduate Research Excellence Scholarship (SUIPRES) which covers the difference between the International and the Home/UK tuition fee for the duration of the PhD/Professional Doctorate programme. All International applications will be considered for a SUIPRES Scholarship. You will be informed whether a SUIPRES Scholarship will be offered within your offer letter.

ATAS

Please note that the programme requires some applicants to hold ATAS clearance, further details on ATAS scheme eligibility are available on the UK Government website. 

ATAS clearance IS NOT required to be held as part of the scholarship application process, successful award winners (as appropriate) are provided with details as to how to apply for ATAS clearance in tandem with scholarship course offer. 

If you have any questions regarding your academic or fee eligibility based on the above, please email pgrscholarships@swansea.ac.uk with the web-link to the scholarship(s) you are interested in. 

This scholarship covers the full cost of tuition fees and an annual stipend of £19,237.

Additional research expenses will also be available.

To apply, please complete your application online with the following information:

1. Course choice – please select Materials Engineering / PhD / Full-time / 3 Years / October

   In the event you have already applied for the above programme previously, the application system may issue a warning notice and prevent application, in this event, please email pgrscholarships@swansea.ac.uk where staff will be happy to assist you in submitting your application.

2. Start year – please select 2024
3. Funding (page 8) –

• ‘Are you funding your studies yourself?’ – please select No
• ‘Name of Individual or organisation providing funds for study’ – please enter ‘RS620 - Fatigue Performance’

*It is the responsibility of the applicant to list the above information accurately when applying, please note that applications received without the above information listed will not be considered for the scholarship award.

One application is required per individual Swansea University led research scholarship award; applications cannot be considered listing multiple Swansea University led research scholarship awards.

We encourage you to complete the following to support our commitment to providing an environment free of discrimination and celebrating diversity at Swansea University: 

• Equality, Diversity and Inclusion (EDI) Monitoring Form (online form) 

As part of your online application, you MUST upload the following documents (please do not send these via e-mail). We strongly advise you to provide the listed supporting documents by the advertised application closing date. Please note that your application may not be considered without the documents listed:

• CV
• Degree certificates and transcripts (if you are currently studying for a degree, screenshots of your grades to date are sufficient)
• A cover letter including a ‘Supplementary Personal Statement’ to explain why the position particularly matches your skills and experience and how you choose to develop the project.
• Two references (academic or previous employer) on headed paper or using the Swansea University reference form. Please note that we are not able to accept references received citing private email accounts, e.g. Hotmail. Referees should cite their employment email address for verification of reference.
• Evidence of meeting English Language requirement (if applicable).
• Copy of UK resident visa (if applicable)
• Confirmation of EDI form submission (optional) 

Informal enquiries are welcome, please contact Dr Elizabeth Sackett (e.sackett@swansea.ac.uk).

*External Partner Application Data Sharing – Please note that as part of the scholarship application selection process, application data sharing may occur with external partners outside of the University, when joint/co- funding of a scholarship project is applicable.