Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - PolyTest (Ultrasonic Phased Array Non-Destructive Testing and In-Service Inspection System for high integrity Polyethylene Pipe Welds with automated analysis software.)

Teaser

• A need arises from greater use of PE pipes with lower capital, installation, operation & maintenance cost and corrosion free service life but is limited through no suitable NDT technique to check integrity of welded joints between pipes. • The objective is to take...

Summary

• A need arises from greater use of PE pipes with lower capital, installation, operation & maintenance cost and corrosion free service life but is limited through no suitable NDT technique to check integrity of welded joints between pipes.
• The objective is to take recently developed FP7 inspection/NDT technology for polyethylene (PE) pipe welds, from TRL6 to TRL9 commercial product, exploited globally by consortium partner providers to the end user, Tier1/2 suppliers and other customers.
• €1.9m of funds is requested from consortium members TWI, M2M, Palad, Tecnitest.
• Money will be used for the enhancement, meeting specific site testing requirements and commercialisation of Ultrasonic Testing technology, software, technique validation, standards and technician training/certification.
• Funds will enable the application specific product enhancements to be made and to support product/service/support commercialisation.
• Target market covers end users, Tier 1/2 suppliers, in Power Generation (Nuclear Power Plant – NPP), Gas & Water Utilities, Mining industry and Process Plant industries, with a total size of 11.5billion welds. Additionally UT equipment, transducers, software suppliers and service inspection/NDT companies will benefit.
• A unique TRL9 product made suitable for industry use i.e. radiation hardened, ingress protected, site ruggedized, automated data analysis software, validated with appropriate standards, will meet target industry specific inspection applications

Work performed

\"D1.1: Scanner hardware ruggedisation. Developments have enhanced the FP7 original system: • PA probes are a standardised format reducing wedge requirements by 50%; butt fusion (BF) or electrofusion (EF) wedge is now capable of being fitted with two probe frequencies according to weld thickness, • array element specification is standardised across all PA probes, • new link grips improve scanner handing and address safety concerns, • manufacturing wedge body in 3D printed polymer reduces cost, quickens lead time and allows rapid redesign of EF wedge for very thick joints, • replacement of NDT competitor encoder with standard commercial item prevents potential conflict of interest, meets project IP67 requirements and fits within the carriage footprint, • link system redesign in lighter materials aids manual handling and transportation of system, • standardisation of mechanical fasteners permits single tool use for every day operations, • redesign of fill and bleed system integrates components into wedge body, reduces parts count, enhances appearance, • carriage design utilises enclosed constant force spring improving probe contact force, includes an ergonomic cover to aid scanner manipulation and reduce dirt ingress. Initial testing with new probe and wedge designs yield good scan data with image improvements, minor work is required on wedge anechoic features to eliminate noise at angular extremities for BF weld scanning. A DOW deviation removes the ‘radiation hardened’ requirement, following expert advice from the Nuclear NPP sector advising that HDPE pipe would not be used in an environment where radiation levels would necessitate ‘radiation hardened’ equipment.

D1.2: Instrument software enhancement and Automatic Defect Recognition integration. The GEKKO PolyTest GUI offers an image based step-by-step interface to define part and PAUT setup configuration for BF and EF inspection. A dedicated analysis panel displays data and offers a range of analysis tools, including the ADR algorithm used instead of manual analysis saving time and simplifying analysis. ADR code is developed to convert scan data from PAUT unit into a format for manipulation in MATLAB to display C-, S- and A-scans with user control. ADR algorithm covers a selected region of interest with GUI widgets \"\"ADR1\"\" and \"\"Validate\"\" used to compare ADR results against manual results.

D1.3: Validation Samples: BF and EF welded samples are required for a number of reasons; to determine the probability of detection (POD) of planar lack of fusion flaws; to validate the automatic defect recognition (ADR) procedures; to validate defect-sizing capabilities of the system; for training and examination of inspection personnel. Each welded joint contains a number of lack of fusion (LOF) flaws of different size with each flaw positioned randomly around the joint and in through wall position for BF welds, to ensure that repeated patterns are avoided to alleviate defect location prediction by system operators. To simulate LOF flaws in a consistent and reproducible way, thin (40μm) aluminium discs are used.
• For BF joints, pipe wall thickness range between 10 and 73mm. Three wall thicknesses ranges will be investigated; 10-15mm, 25-35mm and >50mm. Chosen pipe sizes to cover the ranges are – diameter 110mm SDR11 (t=10.0mm); 315mm SDR11 (t=28.6mm); 630mm SDR11 (t=57.2mm). The smallest flaw should have a diameter of 1mm and the largest flaw a diameter of 8mm or 50% of the pipe wall thickness, whichever is smaller.
• For the EF joints, pipe diameter range between 90 and 800mm. EF fittings from three different manufacturers and three pipe size ranges for each EF fitting manufacturer is being investigated; 90-125mm, 180-315mm and 450-800mm. The chosen pipe sizes that cover these ranges are; 110mm SDR11, 225mm SDR11 and 630mm SDR11. Inserted LOF flaws should be between 2 and 50mm in diameter and, in addition, pipe under-penetration should be investigated, wh\"

Final results

There has been great interest in the PolyTest system from the HDPE pipe installation/utilisation community with the main hurdle being the absence of relevant standards and acceptance criteria. An ASTM standard for BF welds is now in circulation with a standard for EF joints, and the equivalent standards from ISO being under development. There is high potential that the finalised enhanced PolyTest system and its associated certified training is likely to coincide with the release of some of the standards that will trigger a need from end users.
A concept design for system accessories may permit manual non-encoded scanning of reduced access EF fittings and saddle joints with real-time cross sectional imaging of the EF joint fusion zone. Interest exists in the gas utilities sector to use the PolyTest system for smaller bore pipe EF joints (<90mm) and from the water and sewage sector for larger diameter BF welds (>900mmDIA and/or >72mm wall thickness); each would require system re-design and validation to extend the current capability range

Website & more info

More info: http://www.polytestsystem.com.