Encyclopedia of Ocean Engineering

Living Edition
| Editors: Weicheng Cui, Shixiao Fu, Zhiqiang Hu

Catenary Anchor Leg Mooring

  • Liping SunEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-981-10-6963-5_141-1



A typical CALM system consists of the mooring buoy, chain and anchor system, mooring assemblies, and floating and submarine hose strings. The buoy body provides the necessary buoyancy to keep the system afloat. A rotating deck or turntable is mounted on top of the buoy body to transmit mooring force from the mooring assemblies through the buoy to the anchor chains. The CALM anchoring system consists of 4–8 anchor chains extending from the buoy body radially out and terminating at firmly embedded anchors or anchor piles (Luo et al. 2015).

Scientific Fundamentals

System Composition

The CALM system consists of a large buoy, which supports a number of catenary chain legs anchored to the sea floor (Fig. 1). Riser systems or flow lines that emerge from the sea floor are attached to the underside of the CALM buoy. Some of the systems use a hawser, typically a synthetic rope,...
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Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.College of Shipbuilding EngineeringHarbin Engineering UniversityHarbinChina

Section editors and affiliations

  • Liping Sun
    • 1
  1. 1.Harbin Engineering UniversityHarbinChina