BHGE SealBond? cement spacer systems mitigate lost-circulation issues and reduce slurry fallback after placement, preventing induced losses and eliminating costly remedial cement jobs.
In wells with critical fracture gradients, our spacer technology enables the use of standard slurry designs and densities where highly extended or special lightweight slurries were previously required.
SealBond systems minimize filtrate invasion and damage and induced losses while cementing. Based on ultralow-invasion fluid technology, they form a barrier at the wellbore wall to strengthen the wellbore for long-term zonal isolation. With the system’s near 100% return permeability property, formation integrity is maintained for optimized production.
The BHGE SealBond? Plus additive enhances the spacer system’s performance in cases of severe or total loss of returns. This additive allows a SealBond spacer to adhere to the lost circulation zone(s).
SealBond Plus technology is a proprietary blend of 100% organic, biodegradable, lost- circulation materials. Our field-proven blend has been used to seal losses in formations with permeabilities up to 3,500 darcies.
The latest advancement in cement spacer systems, the SealBond Ultra? cement spacer system provides nearly double the sealing and plugging ability of previous systems, while maintaining a superior rheological profile at elevated temperature and improved mud and cement compatibility characteristics.??
The SealBond Ultra system reduces slurry fallback after placement, prevents induced losses, and eliminates the need for costly remedial cement jobs. In wells with critical fracture gradients, the SealBond Ultra system enables the use of standard slurry designs and densities where highlyextended or special lightweight slurries were previously required. This eliminates the need to compromise on thickening times and compressive strength. It is equally effective in fragile, unconsolidated, and fractured formations.
Additionally, the SealBond Ultra system enhances hole cleaning prior to cement placement, by effectively removing gelled drilling fluid by optimizing the flow regime, density, and chemical enhancement properties.
Applications
- High temperature formations
- High permeability formation
- Formations with low fracture gradients
- Fragile, unconsolidated, and fractured formations
Benefits
- Forms a seal to minimize filtrate invasion into the formation for predictable and effective isolation
- Allows increased ECD at casing depth in wells where the fracture gradient limits design density of the cement
- Reduces cement losses and formation damage
- Prevents cement fallback after placement
- Provides wellbore strengthening
- Enhances hole cleaning
- Effective with virtually all cement systems and drilling fluids
- Certified as a OSPAR PLONOR product for reduced HSE risks
SealBond LT Spacer System Helps Isolate Heavy-Fluid-Loss Zone
An operator working in Kenya was preparing to cement the 7-in. casing section of a new well. While running the casing however, the operator began to experience severe lost circulation issues, and had to reestablish circulation after each casing joint was run in-hole. This indicated to the operator that the fracture gradient (FG) was lower than previously thought—which was verified through subsequent analysis—and it became clear that the planned cement program would exceed the FG, leading to lost circulation and failed zonal isolation. With only two days until cementing was scheduled to begin, the operator asked Baker Hughes, a GE company (BHGE) for a re-designed cement program that would achieve the necessary zonal isolation and prevent losses.
After working with the operator’s team to re-design the cement slurries—using CemFACTS? and WellTemp? software to analyze the new data—BHGE recommended the SealBond? LT cement spacer system with the SealBond Plus additive in a ratio of 10 pounds per barrel. The system forms a permeable seal over the formation, mitigating lost circulation issues during cementing and reducing cement loss and formation damage. It helps reduce filtrate invasion, prevent cement fallback, and increase equivalent circulating density (ECD) at casing depth in wells where the fracture gradient limits the design of the cement density. Additionally, the Fiber? lost circulation material would be pumped at 1 pound per barrel with the cement slurry to mitigate losses during the cementing operation.
Because the fracture gradient was low and the zone to be cemented was 7,224 ft (2202 m) long, this newly proposed design needed to be pumped through a stage tool. Discussions with the tool provider were undertaken to confirm the inside diameter of the stage collar ports (approximately 28 mm) and share tool-specific guidelines. This resulted in a tailored slurry design with a lost circulation material (LCM) loading suitable to be pumped through the known tool restrictions.
After the cement was pumped, and despite the reduced slurry weight, post-job logging showed good cement bond and successful zonal isolation, with top of cement (TOC) being achieved as planned. The cementing was finished with no non-productive time (NPT), and the segmented bond log (SBL) showed adequate cement bonding across all zones of interest.
Highly-permeable formations can be a challenge to properly cement and ensure zonal isolation. In Colombia, an operator encountered highly-permeable sand zones, increasing the chances of downhole losses and safety risks.
The key objectives were to assess the situation and provide recommendations prior to running the production liner on the next well in the field. The operator chose to consult with Baker Hughes, a GE company (BHGE), to provide a thorough assessment of previous jobs as well as run simulations to optimize cementing operations for improved performance and to achieve proper zonal isolation.
After reviewing cement evaluation logs on previous wells, it was determined that cementing was affected in front of a highly permeable formation. In addition, the review of a cement evaluation log in preparation for the production liner showed good cement just above and below the target zone. Based on these challenges, BHGE recommended the implementation of its newest cement spacer system, the SealBondTM Ultra. BHGE’s SealBond portfolio of cement spacer systems has been an industryleading flagship technology for more than a decade. Its latest advancement, the SealBond Ultra cement spacer system is an ultralow invasion spacer technology designed to prevent losses while cementing. With nearly double the sealing ability of previous systems, SealBond Ultra mitigates permeable formations by sealing large natural fractures as large as 1 mm in order to effectively cement the well and provide effective zonal isolation.
The production liner job was executed per plan and as directed by the CemFACTS simulation. BHGE provided excellent fluid returns during the production liner job and proper cementing was confirmed with cement logs. Based on this success, the operator awarded BHGE with all of its production liner cementing in all future wells in the field.
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