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Come up with something to prevent the many rejections of PE welds, or soon you won't be allowed to use the method. That was the assignment Netbeheer Nederland received several years ago from regulator State Supervision of Mines. How all those involved joined forces and jointly arrived at an NTA and two certification schemes, two of them explain.
Roger Janssen works at Enexis, one of the Dutch grid operators, and is a member of the board of experts working on the certification schemes for PE electrofusion welding. Previously, he was involved in the development of the NTA 8828. The same goes for Jorn Bronsvoort of certifying body QS, who has also participated in the process from the beginning. That makes them the right people to tell about the process.
Network operators are responsible for thousands of kilometers of gas pipelines lying in Dutch soil. These pipes today are made of a plastic that is fused together using a technique called Polyethylene-Electromof welding. The more accurately this is done, the safer the weld and the longer the lifespan.
The State Supervision of Mines (SSM) is the independent regulator of gas network safety. Inspections several years ago showed that many of the electro-welds were rejected. Too many according to SSM, which announced that the quality had to improve. If this did not happen, an embargo on the method lay ahead.
All market stakeholders decided to join hands to solve the problem. The causes were quickly identified. 'People thought a little too easily about welding technology. There was no specific training, people did it on the side," says Jorn. Furthermore, everyone worked according to their own instructions, which did not help the quality either. The first conclusion was therefore that joint agreements had to be made. Then you quickly end up at NEN if you are looking for an organization that can supervise that process.
Together with industry associations of network operators and contractors, as well as material suppliers and training institutes, the NTA 8828 was developed. This contains comprehensive guidelines for making a good and safe PE connection. Subsequently, those involved drew up two certification schemes containing the requirements for well-qualified welders and welding supervisors. The NTA and certification schemes were created for gas pipelines, but can also be applied to water pipelines, for example.
A solid training course was developed and completed with a theory and practical exam. This was sorely needed, because the requirements of NTA and of the certification schemes do not lie. 'We deliberately set the bar very high, because quality in work is becoming increasingly important,' Roger says about this.
The training departments of the certifying institutions provide the courses. 'We have the knowledge of the technology and know the rules regarding training and practical examinations,' says Jorn. The questions for the theory exam were devised by a group of people from the College of Experts. These are representatives from the market who deal with the development, validation and management of a certification scheme. To ensure independence, exam specialist Cito was asked to supervise the development of the exam questions and administer the theory exams. In this way, the role of examiner remains separate from the role of trainer.
Initially, those involved were not really convinced of the need for SSM's order to make agreements on PE welds. Although many welds were rejected, there had never been a major incident. Meanwhile, the benefits are coming more and more into focus. Roger and Jorn can list a few. One new position is that of welding supervisor. A necessary function. 'If you don't exercise strict control, there is a high risk that the quality of the work will deteriorate,' Roger knows. 'An inferior weld may not immediately give leaks, but it does last much less. A good weld has a lifespan of up to 50 years,' says Jorn.
Also, everyone now works to the same guidelines and far fewer welds are rejected than before. The approval rate has increased in recent years from 80% to almost 100%. One of the consequences of this is that work is not delayed. This is reflected in the cost.
An additional advantage is the ability to keep a good finger on the pulse of the process. Roger: "The welding supervisors see what is going on in the field and can provide feedback on any problems. Then we as a board of experts can investigate whether we need to adjust the certification scheme or the NTA, for example. The training courses also sometimes raise issues that can lead to an improvement of the NTA.'
The NTA and certification schemes have had quite an impact on welders. PE welding is now a specialized profession. 'There are about a third of welders left,' Jorn says. 'A certificate is also a stick to do your job well. Because there are still regular inspections, and if the quality is not good enough, a warning follows. If there are several warnings, the welder loses his certificate and is no longer allowed to do the work. Of course, nobody wants that.
All great arguments for the development of NTA and certification schemes, which not only apply to PE welding, but give the entire standardization and certification process reason to exist. Working according to standards means all working in the same way. With great attention to reliability and safety. Certification results in better professionals. Well trained and attentive to their work.
If you ask Roger what the most important thing about the whole process has been, he knows the answer immediately: the cooperation of all those involved. 'If you have participated in the development of NTA and certification scheme, you also stand behind it and propagate it to the rest of the market.'
Jorn adds, "Everyone had an interest in restoring trust and improving quality. That made it easy to get all parties together.' That applied to the grid managers and the members of Bouwend Nederland, but also to suppliers of materials, for example. These have an interest in being able to continue supplying their materials.
In addition, participation makes it possible to monitor the enforceability of the guidelines and rules. Roger did so as a representative of a grid operator, Jorn on behalf of a certifying body, and other participants sat there with the interests of contractors in mind, for example. Roger: "That regularly caused tough discussions, but always with a joint decision as a result.
Achieving consensus is not always straightforward, "Fortunately, the consultants at NEN are very adept at leading discussions in a good way," Roger reveals.
NEN has an important role in the process. The consultants provide the secretariat for drafting and, if necessary, revising the NTA and the certification schemes. In addition, NEN is the administrator of the certification scheme and of the register. On the NEN website you can find the details of all the certified PE welders and welding supervisors and find the NTA and certification schemes.
