Riser guide system
AssigneeMoss Maritime AS
InventorsHåkon Strømberg, Tom Strandbakken
Life of this patent
Estimating the term…
Abstract
A riser guide system is for use on a floating offshore platform, the platform having a topside and a substructure having a lower pontoon, and at least one riser extends from a subsea location to the topsides. A permanent guide is secured to the pontoon, a primary guide is located in the permanent guide, a secondary guide is located in the primary guide, and riser guides are located in the secondary guide and face the riser. In a method for installing the riser guide system, both the primary guide, the secondary guide and the riser guides are placed around the riser at the topsides, and lowered down to the pontoon.
Claims14
A riser guide system for use on a floating offshore platform, the platform comprises a topside and a substructure having a lower pontoon, at least one riser extends from a subsea location to the topside, the system comprising:
- a permanent guide having the shape of a housing and having a through-going opening for the riser, the permanent guide being secured to the pontoon,
- a primary guide having the shape of a housing and having a through-going opening for the riser, the primary guide being located in the permanent guide and being longitudinally divideable in two or more mechanically interconnectable parts,
- a secondary guide having the shape of a housing and having a through-going opening for the riser, the secondary guide being located in the primary guide, and
- riser guides located in the secondary guide and facing the riser.
A riser guide system for use on a floating offshore platform, the platform comprises a topside and a substructure having a lower pontoon, at least one riser extends from a subsea location to the topside, the system comprising:
- a permanent guide having the shape of a housing and having a through-going opening for the riser, the permanent guide being secured to the pontoon,
- a primary guide having the shape of a housing and having through-going opening for the riser, the primary guide being located in the permanent guide,
- a secondary guide having the shape of a housing and having a through-going opening for the riser, the secondary guide being located in the primary guide, and
- riser guides located in the secondary guide and facing the riser,
- the primary guide is provided with hooks and the permanent guide is provided with at least one holding element engageable by the hooks, for securing the primary guide to the permanent guide.
A method for removing riser guides on a floating offshore platform, the platform comprises a topside and a substructure having a lower pontoon, at least one riser extends from a subsea location to the topsides, the riser guides face the riser and are located in a secondary guide having the shape of a housing and having a through-going opening, the secondary guide is located in a primary guide having the shape of a housing and having a through-going opening, the primary guide is located in a permanent guide having the shape of a housing and having a through-going opening, the permanent guide is secured to the pontoon, the riser extends through the openings of the secondary guide, the primary guide and the permanent guide, wherein the method comprises the following steps:
- lifting the primary guide including the secondary guide up from the permanent guide to the topside,
- removing the riser guides from the secondary guide, and
- dividing the primary guide into at least two parts and removing them from the secondary guide after the primary guide and the secondary guide have been lifted up to the topside.
Dependencies are inferred from the claim text.