Improved Inspection of CRA-Clad Pipeline Girth Welds with the Use of Accessible Advanced Ultrasonic Phased-Array Technology André Lamarre, Olympus Scientific Solutions Americas 11th European Conference on Non-Destructive Testing, Prague, October 2014
Contents Ultrasonic phased-array inspection for pipeline girth weld inspection CRA-clad pipes inspection issues and solution Validation study Automated solutions Summary
ULTRASONIC PHASED-ARRAY FOR PIPELINE GIRTH WELD INSPECTION
Phased-array basics principles Wedge Electronic focusing at different angles without moving the probe Weld Note the rebound on the ID
Phased-array advantages Offers all the benefits of Ultrasonics with the following advantages Increased coverage and detection capabilities through multi-angle, electronic rastering and beam control Imaging and recordable data in manageable file sizes viewable by all parties as needed. Reduced mechanics and difficulties over multi-probe techniques
CSCCAN Weld inspection with portable ultrasonic phased-array instrument: OmniScan PA Typical display ASCAN SSCAN
Automated girth weld inspection system: PipeWIZARD Strong field experience : > more than 180 units in the field > 3 million welds inspected > hundreds operators trained on PipeWIZARD
Advantages of AUT phased-array vs. radiography High probability of detection - Accurate sizing of defects height > less repair using ECA(Engineering Critical Assesment) - No radiation > no hazard > no licensing - No chemical > no waste material - Real-time analysis for instant evaluation and welding adjustment - Setup and inspection reports in electronic format
AUT phased-array vs. radiography
PipeWIZARD qualification All major oil and gas companies already qualified the PipeWIZARD system for one of their pipeline construction projects : Exxon Mobil Shell Chevron PetroChina Total BP CNOOC Sinopec Saudi Aramco Petrobras Eni Kuwait Oil Company and more
Codes governing pipeline AUT inspection ASTM E 1961 API 1104 DNV-OS-F101
Zone discrimination technique Receiver Emitter Zones Cap F5 F4 F3 F2 F1 HP LCP Root Description: - The weld is separated in zones - Emitter and receiver hit each zones - Beam size is adjusted to maintain overlap between zones - Results presented in a strip chart imaging
CRA-CLAD PIPES INSPECTION ISSUES AND SOLUTIONS
Main problems for UT inspection of clad pipes Zone discrimination cannot be used on clad pipes Skipping on the ID of the pipe is hazardeous or impossible because of the clad layer Anisotropic structure and grain size of the weld is difficult to penetrate with transverse waves(sw)
Solution description Acoustic solution who can work on the first leg (without skipping on the ID of pipe) Low-frequency and L-wave configuration to penetrate the weld with sufficient energy Capable to generate surface waves and high-angles to inspect upper part of the weld Easy set-up creation Off-the-shelf instrumentation
Dual matrix array description 7X4 element configuration utilizing 28 elements for the transmitter and 28 elements for the receiver with an aperture of 19 x 12 mm Frequency: 2.25 MHZ mounted on LW wedges Modeling showed it can perform full weld coverage
Dual Matrix Array Capabilities DMA allows to create a sector scan (such as 30 to 70 LW with highresolution) Can adjust the focusing at differents depth in the symetric plane Can adjust the beam size by selecting different aperture sizes Can perform skew angles looking for oblique defects Plus the known advantages of the TRL conventional: No wedge echos (allowing the use of main gain) No dead zones
VALIDATION STUDY
Validation block description Carbon steel pipe with Inconed 625 cladding Inconel 625 weld Outside diameter: 30 in 39 mm CS INCONEL 625 CS 19 mm 40 mm INCONEL 625 CLADDING 3 mm
Reference defects description Toe notch: Centerline notch: Root notch: Height = 2 mm; Length 10 = mm Height = 2 mm; Length 10 = mm Height = 2 mm; Length 10 = mm Side Drilled Hole 1: Depth 1/4T = mm; Diameter = 2.5mm Side Drilled Hole 2: Depth 1/2T = mm; Diameter = 2.5mm Side Drilled Hole 3: Depth 3/4T = mm; Diameter = 2.5mm
Equipment description Dual Matrix Array : 2 x (7x4) elements: @2.25Mhz OmniScan: MX2 Phased Array Module : PA2 32-128 PR TomoView (2.10R12) Software (Not mandatory, DMA could be used with OmniScan only, import.law file required) Set-up Builder Software 1.0R5 (Mandatory to compute focal laws) PROBE: 2.25DM7X4PM-19X12-A17-P-2.5- OM: (U8331715) WEDGE: SA17-DN55L0- IHC (U8831948)
Weld inspection scenario DMA probe used to assure full coverage with 2 Sectors Scan Each sector covers a range of angles from 35 to 76 deg LW One sector focused at 2 mm depth The other sector focused at 20 mm Gain is adjusted to maintain noise level below 20% for all angles Inspection is done manually without scanner L wave angle from 35 to 76 Full Coverage with correct SNR detection required 2 groups Group 1 : Focal Depth = 2mm, Gain = 50dB Group 2 : Focal Depth = 20 mm, Gain = 45 db
Detection of reference defects in the weld volume HOLE ¼ T Focal Depth = 2 mm Gain = 50 db Optimum angle = 75 Focal Depth = 20 mm Gain = 45 db HOLE ½ T HOLE ¾ T Optimum angle = 59 Focal Depth = 20 mm Gain = 45 db Optimum angle = 54
Detection of reference surface notch at the toe position TOE NOTCH (depth ~ 2mm) Focal Depth = 2 mm (Gain = 50 db) Focal Depth = 20 mm (Gain = 45 db) Optimum angle = 65
Detection of reference surface notch at the center of the weld CENTERLINE NOTCH Focal Depth = 2 mm Optimum angle = 76
About surface breaking flaws This probe wedge combination can detect a surface EDM notch up to 50mm from the wedge face.
Conclusions of the tests A 2.25 MHz DMA probe paired with the OmniScan MX2 32:128 PR can be advantageous for the inspection of CRA-clad pipelines with large diameters. Full coverage of the dissimilar weld was ensured. SDHs located in the volume and notches located on the ID and OD can be detected using an inspection scenario of two groups steering the beams from 30 to 76 LW, focusing at 2 and 25 mm.
AUTOMATED SOLUTIONS
Integration to automated solutions The next step is to integrate this solution with scanner to perfrom high-productivity inspection of pipes Semi-automated solution with the Chain Scanner Full automated solution with the PipeWizard
Semi-automated solution: Chain scanner Calibration verification scan on 5% ID notch. Chain scanner description: Manual encoded scanner One or 2 axis Pipe range OD: 1.75 in to 38 in CRA-clad pipe solution already integrated Inspection scan on production weld.
Automated solution with the PipeWizard Integration in process for highproductivity inspection PipeWizard has all the tools to assure succesful integration Sector scan and weld imaging Set-up creator Completion target date: December 2014
Summary A 2.25 MHz DMA probe paired with the OmniScan MX2 32:128 PR can be advantageous for the inspection of CRA-clad pipelines with large diameters Full coverage of the weld is ensured and all referenced defects are found Some players of the industry have already adopted this solution integrated with the off-the-shelf instrumentation and software of the OmniScan Olympus is working to integrate these tools to the PipeWizard to provide a fully automated CRA-clad pipeline solution
Thank you Questions?