Ringhals AB near Gothenburg is the Nordic Region's largest power plant, producing approx. 20% of Sweden's electricity consumption. The power plant has used FORCE Technology to carry out inspections at its installations for more than 15 years. This collaboration has always been extremely close, despite the existence of national boundaries.

Claes-Göran Bengtson of Ringhals AB is a supervisory engineer and has been on the staff for 25 years. He was thus involved in the decision to choose FORCE Technology as partner back in the late 1980s.

"We chose FORCE Technology for a number of reasons. Partly because FORCE Technology's personnel are proficient when it comes to mechanical testing systems and its equipment is always cutting edge. The short geographical distance between FORCE Technology in Brøndby and Ringhals AB is another advantage. The journey takes less than three hours by car.

Shut-downs must be swift – they make tremendous demands

Because nuclear power is a field full of restrictions, FORCE Technology's first task was to certify a number of operators who would subsequently be in a position to carry out the inspections. In physical terms this meant that a few key individuals were selected, who since then have visited Ringhals AB several times a year to perform the tests.

"In the pressurised water reactors are a number of pressure regulators, known as pressurisers, and various nozzles on these pressure regulators are subjected to ultrasonic testing at each inspection." "These components are critical, so our operators have to be more than just well-trained. They also have to be efficient if they are to complete the inspections in the shortest possible time," explains Hans Ole Olsen of FORCE Technology's Advanced NDE Services.

The inspections themselves are done using ultrasound – and the object of examining the welds is to ensure secure operation of the reactors at Ringhals AB.

"We typically earmark a week to examine five welds. Much of the time is spent waiting for other people, because during shutdown there are a lot of us who have to perform examinations and maintenance. There is also a limit to the number of people who can be inside at any one time, so we have to take it in turns to go in." The shut-down itself is planned in good time, and the whole point is to achieve as swift a shutdown as possible. "In reality, all we have to do is to go in and carry out our examination as quickly as possible, pack up my things and go home," says Hans Ole Olsen.

Key personnel the same after 15 years

"I have been involved for 15 years, and the contact personnel are still the same. Our chemistry is extremely good, and because we know each other so well after many years of collaboration, our relationship is without friction. We have had no conflicts and therefore very much hope that our collaboration will continue," explains Claes-Göran.

Swedes sent on courses in Brøndby

"At the same time, it is necessary to keep up to scratch on our technical skills and understanding of the testing techniques, so something else we have made quite a lot of use of is FORCE Technology's training centre in Brøndby. Many of my colleagues and other people from here have been on courses, where the same personalities have received us time after time. Working with a partner when so many contact personnel have followed us through the years has been easy and uncomplicated. So we also hope that we will continue to benefit from the expertise of the staff at FORCE Technology."

Over the last 3-4 years, Ringhals AB and FORCE Technology have been in close contact in order to plan the inspections. "In this respect it is a tremendous advantage to work with the same people. Because they know our plant as well as we do, everyone makes efficient use of the time available. Our routines here at the power plant have also become FORCE Technology's routines, which makes the entire process – and our collaboration – much easier," concludes Claes-Göran Bengtson of Ringhals AB outside Gothenburg.

About Ringhals AB

Ringhals AB, which is part of the Vattenfall Group, one of the Nordic Region's largest energy companies, is one of four nuclear power plants in the world which both has boiling water and pressurised water reactors. The power plant's four reactors produce enough electricity in a normal year to provide for Gothenburg's consumption six times over.