Foam cementing can provide wellbore integrity, ensure proper zonal isolation, and protect the environment while offering significant benefits over traditional cement applications. Its unique properties:
Permit flexible job designs
Provide superior hole cleaning and coverage in non-gauge wellbores
Offer improved thermal insulation
Deliver superior mechanical properties at lower densities.
Foam cementing is an ideal solution for shutting off shallow water or gas flows and in applications with narrow pore pressure windows. And, because a small foam slurry can effectively expand to cement a larger section of the wellbore without compromising set cement properties, the volume of bulk cement and additives required for a job is minimized—significantly improving economics in large-volume applications.
The Baker Hughes FoamSetTM cementing system is designed to provide wellbore integrity and ensure proper zonal isolation for diverse environments. The versatile, all-liquid FoamSet system saves time and money by mitigating lost circulation as well as shallow water/gas flows. The system also improves fluid displacement efficiencies as compared to conventional cements.
Achieve improved cleanup and displacement
Conventional Cement ：Insufficient contact time or contamination can result in poor mud removal by a spacer system.；Mud debris or an oil-wet surface can prevent a good bond when the cement forms, compromising zonal isolation.
FoamSet Cement ：The highly viscous FoamSet slurry provides additional cleaning and debris removal as it expands over the desired zone—helping overcome a compromised spacer application, if necessary；The properly conditioned wellbore permits a reliable cementing operation for superior zonal isolation—minimizing the risk of annular gas or water migration and eliminating the need for costly remediation and squeeze- cement operations.
With any cement job, spacer design and application are crucial. Even thin layers of synthetic or oil-base drilling fluid on the casing or formation can prevent a slurry from forming a good bond to these surfaces. Without that bond, it is difficult to achieve effective zonal isolation and often results in costly remediation.
Minimize losses in weaker formations
Conventional Cement ：Heavier conventional fluids are known to induce fractures in weak formations；Conventional cement slurries follow the path of least resistance and often travel directly up the annulus—bypassing faults, thief zones, and gaps in an irregular wellbore.
FoamSet Cement：The energized FoamSet system expands across the annulus and into fissures, cracks, voids, and washouts—ensuring proper zonal isolation；FoamSet slurries deliver superior set properties at a relatively low hydrostatic pressure to minimize induced fracture risks or formation breakdown and the resulting losses.
Whether it results from a weak, unstable formation, a low fracture gradient, or a fault or another type of thief zone, it is very difficult to properly seal an irregular wellbore or one prone to losses. With conventional cement systems, the slurries tend to follow the path of least resistance. This can result in voids and gaps in the cement and also poor zonal isolation.
The FoamSet slurries can be engineered to deliver superior set properties at relatively low densities. This minimizes the risk of an induced fracture or formation breakdown that could lead to losses.
Control shallow water and gas flows
Conventional Cement ：Shallow gas or water flows can contribute to unwanted communication between zones；Shallow water/gas flows can infiltrate the wellbore and increase the risk of losing well control, as well as result in sustained casing pressure.
FoamSet Cement：Pressure in the system’s N2 bubbles compensates for volumetric losses as the cement sets，FoamSet helps hold formation fluids in place during the critical static gel strength phase；N2 bubbles in the FoamSet system enhance fluid loss control；The system’s improved coverage creates more torturous paths for influxing fluids to pass through—limiting invasion risks.
Controlling shallow water and gas flows is critical to rigsite safety and wellbore integrity. Should these flows occur, there is a substantial risk of interzonal communication and, in a worst-case scenario, the possibility of losing control of the well. During cementing operations, wells are especially susceptible to shallow water and gas flows as the slurry transitions from a liquid to a solid.
The FoamSet system offers increased protection against these hazards because it maintains a more constant pressure to keep the water or gas in the formation and out of the cement in the annulus.
integrated foam cement solution
In addition to its use in job design, the CemFACTS software also provides field personnel with an invaluable real-time simulation tool if unplanned events force them to deviate from plan—allowing them to update job parameters and proactively address any potential issues before they occur.
CemFACTS is also used for post-job analysis, and that knowledge is incorporated into future jobs to help accelerate learning curves and the adoption of best practice.
Deploy state-of-the-art process control
In the past, some operators have been slow to embrace foam cement due to the perceived added risk associated with an energized system. However, with Baker Hughes’ new automated process control system, the application of a FoamSet system is safer and more efficient than most conventional cementing deployments.
With real-time monitoring and control, the system can automatically adjust the nitrogen injection rate to precisely mirror the job design, regardless of whether the plan calls for a constant nitrogen ratio or a constant slurry density.
And each operation is staffed with a crew possessing advanced classroom and field training on the application of foamed cement systems. This experienced field team is assisted 24/7 by a network of engineering and laboratory support personnel.
Benefit from customized offshore and onshore cementing systems
Each FoamSet application is executed using an automated system designed to provide the critical performance and reliability required by the operating environment—whether offshore or onshore
Count on flawless field execution
Because foam cementing applications presenttheir own set of unique challenges that must be addressed, our teams undergo rigorous, specialized training. This includes both classroom sessions and hands-on training with the foam cementing equipment. The individual learning is supplemented with a full week of team training that teaches all four core members of a foam cement team (Field Coordinator, Field Specialist, Field Engineer, and Nitrogen Supervisor) how to better understand the critical role they play and how their work impacts the work of others.
Subsequent to the training, these crews undergo competency reviews to ensure that they are following the necessary processes and procedures. If any competency gaps are identified, supplemental training is implemented immediately to address the problem.
Applications
Offshore/deepwater environments
Geothermal wells
Horizontal and extended- reach applications
Wells prone to lost circulation nnSingle-stage cement jobs with long columns
Wells with narrow pressure windows
Features and benefits
Enhanced mechanical properties nnImproved zonal isolation nnFlexible designs and formulations
– All-liquid additive slurry designs allow for system modification on location
Improved hole cleaning and increased coverage in non-gauge wellbores
Superior thermal insulation properties
Enhanced shallow hazard mitigation
– Performance properties reduce impact of shallow water flows, shallow gas, and hydrate disassociation
石油圈
