Cellar deck centralizers

CELLAR DECK CENTRALIZERS ARE INSTALLED AT THE CELLAR DECK LEVEL TO PROTECT THE UPPERMOST SECTION OF THE CONDUCTOR AND REDUCE FLOWLINE MOVEMENT TOLERANCE.

Cellar deck centralizers consist of two halves that clamp to the guide or to the deck structure. The method of the interface depends on the conductor guide type. The design includes the use of adjuster shoes with a moulded polyurethane layer to ‘cushion’ the interface with the conductor and prevent wear. The clearance is adjusted to a minimum – some clearance is required for riser axial expansion and movement. These centralizers are typically suitable for standard lateral loads at the level of 2-7 tonnes, although Claxton has supplied units capable of withstanding up to 30 tonnes of lateral load. Working to specific project requirements to provide a design that interfaces seamlessly with the rest of the components, the primary purpose of this type of centralizer is to prevent excessive flowline movement to avoid fatigue issues that would negatively affect the life of the well.

There are four main types of cellar deck centralizer, each requiring slightly different designs:

• Internal – The centralizer is fitted inside a guide can
• External – The centralizer is fitted around a guide can
• External Cone – The centralizer is fitted onto the cone of a guide
• Rectangular – The centralizer is fitted directly into an opening in the deck structure.