Manual Phased Array for small diameter offtake weld inspection.

Completed

Fossil Fuels: Oil Gas and Coal(Oil and Gas, Refining, transport and storage of oil and gas)

Applied Research and Development

PHYSICAL SCIENCES AND MATHEMATICS (Metallurgy and Materials)
ENGINEERING AND TECHNOLOGY (Mechanical, Aeronautical and Manufacturing Engineering)

Not Cross-cutting

Project Contact
National Grid Gas Transmission

Network Innovation Allowance

Ofgem

01 December 2013

01 April 2014

4 months

£56,000

Technical Consultancy

London

Network Innovation Allowance

Project Contact, National Grid Gas Transmission

The objectives of this project are to determine if MPA can be used to detect the presence of subsurface defects in the fillet and butt welds of small diameter branch offtakes, and if so, to develop the method into a fully specified practical technique. Provide National Grid with detailed knowledge about the MPA technique and its applicability for use in the NTS in detecting defects in the butt and fillet welds of small branch offtakes.

An investigation found that subsurface weld defects enabled a gas leak to occur during grit blasting operations on a 2" offtake branch. Detection of these defects using normal NDT techniques such a radiography and manual ultrasonics is not feasible due to the geometry of the components. Such leaks present a risk to personnel and could also result in plant being shut down until the failed component can be replaced. Phase 1 - Feasibility Study (£56,000)The first stage of his project will use the latest available Manual Phased Array (MPA) equipment and a highly skilled practitioner, to inspect four branch offtakes. The offtakes (two defect free, two with defects) will be made up for the project and the work will be conducted under laboratory conditions. It will be conducted as a research project rather than as a blind trial to enable the practitioner to experiment with combinations of transducer heads, operating parameters, signal processing etc. The deliverable from stage one will be a technical report detailing the work undertaken, a review of the findings along with recommendations as to whether MPA can be used for inspection of these components. Phase 2 - Methodology Development (not part of the £56,000, to be costed on completion of phase 1)Further work will be required to develop the specific requirements to enable the technique to be used within National Grid. This will include items such as equipment specification, user guidance, best practice, probability of detection etc. It is anticipated that a blind trial under laboratory conditions and a field trial at an operational site will be required using a range of MPA suppliers. Phase 3 - Business readiness (not part of the £56,000, to be costed on completion of phases 1 and 2)This phase will embed the findings within the business through production of new, and modification of existing company policy, standards and work procedures to ensure fitness for purpose when implementing across the NTS.Note : Project Documents may be available via the ENA Smarter Networks Portal using the Website link above

12/09/18