TotalSealCare at the Unterweser nuclear power plant

Successful on-site service of the product area packings & static seals

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Sales locations

Situation

  • Nuclear power plant Unterweser in Germany with mechanical seals, supply systems for pumps, compression packings and static seals by EagleBurgmann
Product portfolio

Challenge

  • Planned inspection of all gaskets and stem sealing kits; unforeseen increase of the workload by a tenfold
Advantages (big)

Solution

  • Fully equipped service container on-site with two sealing experts, who conducted an extensive on-site service

The Unterweser nuclear power plant (KKU) is operated in Stadland in the Wesermarsch district of Lower Saxony by E.ON Kernkraft GmbH. It supplies some 3.5 million homes with electricity. KKU came on line in 1978, and was the largest nuclear power plant in the world at the time. The net output is 1,300 megawatts; around 10 billion kWh are fed into the supply networks every year.

Right from the start, EagleBurgmann has supplied seals for the various parts of the plant (including mechanical seals and supply systems for pumps in the primary and secondary circuits, along with compression packings and static seals). In addition, the Packings & Static Seals (PSS) product area has been able to demonstrate the performance of its on-site sealing services for nuclear power plants to the total satisfaction of the operator.

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For a planned inspection, a service container manned with two sealing experts and fully equipped with machinery, tools and sealing materials was set up on site. This allowed instant access to over 70 different gaskets and compression packings. For unforeseen cases, immediate support could be called from Burgmann Wolfratshausen and the nearby service center.

The assignment was to supply and fit all the gaskets and stem sealing kits for the components removed for inspection. This service focused on stem and housing seals for valves in all areas of the power plant. A stock of sealing materials was defined and set up in the mobile container on-site before the inspection started. The service also included the preparation of complete documentation and certification for all fitted seals (nuclear quality), in addition to the production of gaskets on-site. This demanded great flexibility from the personnel (who even had to act as valve specialists), and they all needed the appropriate work permits.

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The scope of the work expanded noticeably in the course of the inspection period. For example, the number of seals that the customer originally thought would be necessary increased almost tenfold. The work included:

  • Production of over 600 gaskets from sheets on site
  • Special seals up to 2,400 mm diameter
  • Rapid procurement of graphite packings and cover plate seals
  • Identification of all seals fitted with a label printer
  • Production of certificates for all seals
  • Management of all the fitted seals and electronic reconciliation with KKU

As the seals were kept in stock or procured by EagleBurgmann, there was no need to make use of the operator’s own seal stock. This alone meant considerable savings in terms of administrative effort. Other positive points:

  • All the certificates were issued at a central point at KKU and were thus immediately available
  • Very fast response times to unscheduled works
  • Expert and experienced contacts on site
  • Even materials that were not planned in advance could be quickly supplied
  • Special seals were quickly procured and made available
  • Straightforward documentation process for creating the documentation for KKU
     

According to Jörg Möller, head of mechanical engineering at the Unterweser nuclear power plant: “It was very important that the EagleBurgmann personnel were well-versed in the special documentation and certification requirements demanded by the nuclear industry. Considerable flexibility was also needed. The fact that over 600 “unscheduled” gaskets ultimately had to be produced on site was a massive challenge that they met brilliantly. Thank you so much for your super commitment.”