Continuous Circulation Systems
Enables continuous circulation during the drillpipe connection process for drilling and tripping narrow pressure window wells and providing continuous hole cleaning
Since the introduction of conventional rotary drilling, the process of pumping drilling fluids into the well has been interrupted in order to turn pumps on and off every time a new joint of drillpipe is added to (or removed from) the drillstring. Continuous circulation is the ability to maintain uninterrupted flow of drilling fluid into the well throughout the process of adding drillpipe joints to (or removing these joints from) the drillstring. This process improves the success rate for challenging projects such as wells with narrow pore pressure/fracture gradients, along with high-pressure/high temperature (HP/HT) wells and extended-reach wells.
The e-cd™ and e-cd Plus continuous circulation systems are used in drilling and tripping operations, enabling the pumps to continue running while making connections. This keeps the bottomhole pressure constant during these activities, maintains the same fluid rheology and temperatures, and ensures that the cuttings are kept moving at all times.
The e-cd™ system is an Eni patented system used as a standalone system or in conjunction with managed pressure drilling (MPD) operations to enable continuous circulation – the ability to maintain uninterrupted flow of drilling fluid to the well via the drill string during connections while drilling and tripping out of the hole.