Radolid Caps on Subsea Applications

Radolid protective caps are now being used by APL UK to protect the bolts on their specialised subsea and FPSO swivel systems. The swivels are an integral part of offshore oil and gas production and transfer. The caps are being used for their corrosion protection properties, offering an expected operational life of between 15 to 20 years in the extremely harsh environment.

On all swivels, the Radolid caps are grease filled and remain in-situ throughout their working life. “We are very happy with the corrosion protection that the caps are giving us,” commented Mike Seath, General Manager for APL UK, “they are now a standard component for us on all swivels.”

The subsea swivels connect a subsea loading hose coming up from the sea bed to the shuttle tanker, with one side of the swivel remaining geo-stationary and the other side vessel-stationary. This allows for any movement of the shuttle tanker. The caps are also being used on swivels on the deck of the FPSOs to give exposed bolting corrosion protection from salt spray and humidity.

James Walker RotaBolt is the exclusive distributor of Radolid caps in the U.K and offers the caps as part of its comprehensive joint integrity service. The caps provide robust protection for bolts, bolt ends, nuts and screws. Manufactured by Radolid in Germany, the caps offer almost total protection against corrosion, humidity and operational damage and can be used in a wide range of applications and environments.

The caps have a unique design which features a special clamping edge and sealing lip. They were developed by Horst Thiel, the founder of Radolid, who first got the idea after struggling to change rusted wheel nuts on his VW Beetle.

The current range encompasses a wide variety of caps, from self-cutting threaded caps through to special caps for Allen screws and the latest additions to the range, the ESW/EBM caps, have been specially developed for use in offshore applications and feature a see-through cover.

The caps can also be used in conjunction with two high performance lubricants, Graphite and Molyon, which are now available direct from James Walker RotaBolt as part of the same offer. In addition to their anti-seize qualities, the lubricants help to minimise effort by reducing tightening torque, fostering better and more controlled tightening conditions, as well as having the added benefit of reducing wear on all tooling.

Radolid caps are providing protection in industries such as offshore, wind energy, engineering, processing, manufacturing and transport, reducing maintenance costs and down-times and helping to improve operational efficiencies.

About Rotabolt:

James Walker RotaBolt is a member of the James Walker Group. This global manufacturing group, with an annual turnover in excess of £190-million (Euro 240 million), operates through two strategic business units: Sealing Products & Services, and Rail Systems & Products. It has 50 production, engineering, distribution and customer support sites worldwide and sells in over 100 countries.


Rod Corbett

Tel: +44 1384 214 442