Phased Array Training
November 3, 2011
As a supplier in phased arrays, Olympus NDT organizes AUT training courses on phased arrays and related subjects. These courses are comprehensive, but are primarily aimed at the lower end of the market, i.e. portables and related instruments. The rationale is that higher-end instruments typically require specialized, well trained operators, while limited application instruments require “go/no-go” interpretation. This leaves a large market for portable phased array instruments requiring general training and certification.
One of the main limitations of training is the requirement to be “certified.” Not surprisingly, certification means different things in different countries. Europe and Asia are working on harmonizing EN 473 and ISO 9712, while North America is working on a different approach. With the U.S., the dominant player in North and South America for NDE training and certification, ASNT has modified the ISO qualifications accordingly. The ASNT-modified ISO 9712 document is reduced, compared with the original ISO document, and the differences between the ASNT ISO version and the global ISO 9712 are illustrated. ASNT is also looking at a new phased array approval process, which would use standard headings, formats and questions for training, but it is unclear when this will be approved. Conveniently, the Nuclear Research Commission has also required improved certifications (i.e. with a blind examination), and the ASME NDE (ANDE) program was developed accordingly.
Hopefully, this will introduce North America to global certifications for NDT training. This would resolve one of the major issues facing manufacturers–a globally accepted phased array certification program.
However, time and again, training has proven to be the limiting factor with phased arrays. One of the main objectives to improve training is to illustrate that certification is a key. Specifically, there are two main factors to look at for training, though as a viewer, not as a regulator:
Ensuring that all operators have globally recognized certification works reasonably well in Europe, Asia, Australasia and maybe Africa where ISO 9712 (3) and its related codes-EN 473 (4), PCN and CSWIP-are functioning. However, this leaves us with limitations in North America, where ASNT (American Society for Non-destructive Testing) is dominant.
North American CertificationsASNT has two types of certifications: one is the well-known company certifications, which have their uses (5). To quote, “Employers are responsible for administering the visual acuity, practical and any job-specific examinations required by their written practice to complete the certification process.” This type of certification is company-specific and cannot be transferred by the operator on changing jobs.
The other certification is the ASNT Central Certification Program (6) or ACCP, which is exam-based and transferrable. Neither certification includes advanced techniques like phased arrays and Time-Of-Flight Diffraction (TOFD). Thus there is a hole in North America’s advanced (read: phased arrays) NDT certifications, which is covered elsewhere in the world. According to the ASNT web site, the ACCP Level II UT meets the ISO requirements (though which version of ISO is not clear). ASNT is developing a Body Of Knowledge (BOK) for phased arrays, supplied by one of the Olympus NDT Training Academy Members. This is work in progress, though apparently the outline has been published.
ASNT has developed their own version of ISO 9712 (7), with local adaptations – as permitted by the World Trade Organization. Here, we have some interesting modifications, for example, reducing the required hours for Level II Phased Array training from 80 to 40. In reality, these changes may not be globally acceptable, as Non Tariff Barriers (NTBs) may be erected to eliminate North American manufactured products in export markets.
North American Nuclear CertificationsThere are also nuclear-specific qualifications, in both Europe and North America. In Europe, we have the ENIQ (European Network for Inspection Qualification) (8). This is more of a general framework, with each country having qualification rights to regulate NDE procedures and techniques. ENIQ allows judgment in assessing the need for and extent of physical trials in demonstrating adequate performance.
In the USA, ASME has recently supported another type of qualification, through ANDE (ASME Non-destructive Examination). ANDE does not use ASNT as a certification body, but uses the ASME certification instead from Section XI Article VII 4000 on Qualification Requirements (9). Thus, for a direct-to-Level II candidate, 80 hours of classroom training would be needed (plus experience, of course).
ANDE is developing a Body Of Knowledge, which will cover all techniques, e.g. UT, EC, MT, PT, and phased arrays as well. Perhaps the main question for ANDE certifications is: “Will they be acceptable outside the North American nuclear industry?”
In contrast, the qualification requirements for (non-nuclear) ASME Section V Article 4 for AUT inspections (10) reads:
“Only qualified UT personnel trained in the use of the equipment and who have demonstrated the ability to properly acquire examination data, shall conduct production scans. Personnel who analyze and interpret the collected data shall be a Level II or III who have documented training in the use of the equipment and software used. The training and demonstration requirements shall be addressed in the employer’s written practice.”
There are differences between ENIQ and ANDE. Specifically with ENIQ, there is no qualification of equipment and probes by themselves. As each inspection procedure is case-by-case, a manufacturing company cannot develop a general inspection process to get its equipment qualified. Only service companies can run qualification of their NDT system, which includes procedure, manpower, instrument and probe.
With ANDE, there is the possibility/probability of getting equipment approved by EPRI to go onto their acceptance list. As such, the direct involvement of an inspection company per se is not essential.
And Where Now?So, where does certification stand in North America? Reading this article, it sounds like North America is in major disarray, but in practice things are not that bad. Specifically, Olympus has been encouraging the introduction of ISO-related phased array training courses into North America, with some success. Lavender International is introducing PCN courses (ISO-related) for phased arrays and for TOFD; Davis NDE and Eclipse Scientific are also introducing ISO-related courses.
In addition, other companies outside North America, like Global School of NDT and Jubail Industrial College, are developing ISO courses. Given that it has taken years to get EN 473 and ISO 9712 to settle minor differences (11), our progress can be considered as reasonably brisk. However, the situation will be more comfortable when all trainers can offer globally-acceptable phased array certifications, most likely based on the ISO model.
Not surprisingly, there are issues with the ISO approach as well. For example, ISO breaks down components into several sectors.
The other issue, from one perspective, is the number of hours appropriate for training. For example, when Olympus started training, it ran a two day course only–called “Introduction to Phased Arrays”. Naturally, this course was not planned for qualifications, but proved woefully inadequate in terms of certification. This course was really only useful for engineers and managers, to get an idea of what phased arrays could do. Training courses have now expanded to 40, then 80, hours–many in keeping with ISO, PCN and other certifications. In fact, some training companies are even offering (private) courses of three or more weeks.
ConclusionsThe phased array training programs, like Olympus NDT’s, have been very successful. Ideally, the industry could benefit from seeing all courses using the same certification. There is a significant difference between ISO-controlled certifications and ASNT-company certifications–for both global acceptance and for content. In other words, there is a mish-mash of certifications, but we are slowly iterating towards acceptable, transportable certifications–probably ISO 9712. NDT
References3. ISO/DIS 9712: 2005. “Non-destructive testing – Qualification and certification of personnel”.
4. EN 473: 2009, “Non-destructive testing - Qualification and certification of NDT personnel - General principles”.
7. ANSI/ASNT CP-106 (ISO 9712:2005, Modified), “Nondestructive Testing – Qualification and Certification of Personnel”, 2008 Edition.
9. ASME Section XI Article VII-4000 “Qualification Requirements”, 2010, p. 277.
10. ASME Section V Article 4 Mandatory Appendix VI, “Ultrasonic Examination Requirements for Workmanship Based Acceptance Criteria”, 2010.
11. For more information, visit www.nordicinnovation.net/article.cfm?id=1-834-685