Continuous Circulation Drilling System

Continuous Circulation Drilling System in use on Kvitebjorn Platform

The "CCS" is a device developed by Maris under ITF sponsorship and supported by Shell, Statoil, BP, BG, Total, Veba, EMI and CDL.

The "CCS" enables continuous mud circulation to the drill string while making drillpipe connections.

No other MPD (Managed Pressure Drilling) method maintains continuous mud circulation and constant ECD.

No other MPD method maintains a steady pressure over the entire exposed formation from the bit to the last shoe, throughout the drilling of each section; or continuous cuttings transportation.

This JIP (Joint Industry Project) is now at the fully commercial stage. NOV (National Oilwell Varco) have been operating with two CCSs, very successfully for ENI onshore in Italy and offshore in Egypt, and then offshore in the North Sea for Statoil Hydro for full field development, and now ConocoPhillips and Petrobras. All these wells could not have been drilled without excellent MPD (Managed Pressure Drilling).

NOV and Maris are continuing to develop this new "Technology" for application to UBD (UnderBalance Drilling), ERD (Extended Reach Drilling) and HPHT (High Pressure High Temperature) wells and for many other applications that require excellent 'Managed Pressure Drilling'.

Some of the many advantages of using the "CCS" are:

Maintains constant mud flow and cuttings mobility
- reduces cuttings bed formation in lateral and ERD wells
- reduces the likelihood of a stuck bit or BHA
- provides an even distribution of cuttings throughout the annulus
- maintains an even temperature throughout the annulus
- provides a steady loading of the mud cleaning equipment
- eliminates circulation time before making connections
- eliminates re-drilling of settled cuttings & debris after making connections
- eliminates need to circulate out accumulated gas after connections in UBD wells

Increases safety
- kicks are less likely due to absence of stop/start pressure transients
- kicks are easier to identify in the absence of stop/start transients
- immediate response to kicks as drillpipe is always connected to the mud supply
- circulating mud pressure can be immediately adjusted while making connections
- kill pressure can be maintained while re-installing drillpipe to bottom, if necessary
- accurate tool joint alignment and 'soft landing' reduces thread damage and bad connections

Continous Circulation Drilling System