When starting and pressurizing the systems on Åsgard A and B, the packing boxes on the Bonney Forge valves that were installed on the gas lines failed.
Statoil (equinor) then invited div. packaging suppliers to the Rotvoll research center to test their proposed packaging solutions.
Fuglesangs recommended shortening the packing box with split graphite sleeves and packing with Chesterton 1600 - (3 - 5 packing rings).
This solution was chosen both because of it. low emissions - below 50 ppm, and low friction. Ie the valves were still operable by hand.
In the years 2001 - 2002, 7 - 8000 Bonney Forge valves on gas - 580 bar - were re-packed with Chesterton 1600 gasket on Åsgard A and B.
Of these, less than 10 valves have been repackaged in 18 years.
Reference Specialist mechanical Åsgard A and B - Tore Kristian Rothaug.