Bruce Anchor GP chosen as first ever anchor on R6 chain project

Bruce Anchor was asked to supply twelve drag embedment anchors for the SHEN LAN TAN SUO rig, the first MODU in the world to use 89mm ultra-high-strength Grade R6 anchor chain for the mooring lines.

Project: CMH-182

Client: China Merchants Heavy Industries

Location: Jiangsu Province

Acteon product and service line brands involved: Bruce Anchor, InterMoor, Seatronics, UTEC

The challenge

Bruce Anchor, a brand in Acteon’s Engineering, Moorings and Foundations division, was asked to supply twelve drag embedment anchors for the SHEN LAN TAN SUO rig, a brand new build Mobile Offshore Drilling Unit (MODU), the first in the world to use 89mm ultra-high-strength Grade R6 anchor chain for the mooring lines. The rig is classed by DNV and China Classification Society (CCS).

The anchors for this project had to be 15mT in size but proven as having an ultimate holding capacity (UHC) of over 700mT in a medium clay seabed condition.

Assuming we could carry out the test, a location had to be found with a medium clay seabed.

The solution

Our proposed solution was the Bruce GP anchor. Whilst this anchor has been successfully used all over the globe for many years, we needed to confirm the anchors’ UHC through formal offshore tests.

Bruce Anchor, a brand in Acteon’s Engineering, Moorings and Foundations division, contracted sister companies UTEC Geomarine and InterMoor to locate a suitable test area and carry out some Cone Penetration Testing (CPT) samples to ensure the correct seabed condition was available for an accurate test to be carried out.

The CPT tests were carried out, at a suitable location in the North Sea. Bruce contracted InterMoor again for the offshore installation and Seatronics, for observation support, with the VALOR ROV.

the result

The test was carried out at scale, with a 1.5mT anchor, which had to have a 84mT UHC to represent the 700mT UHC of the 15mT anchor. The tests were completed successfully and exceeded expectations: the 1.5mT anchor, which was used for the test, pulled in excess of 200mT, compared to the goal of 84mT.

Working with complementary Acteon brands allowed us to provide an integrated service, providing ‘in-house’ knowledge and expertise to complete every aspect of this project, from confirming the best location through survey to offshore installation and ROV observation.