VersaFlex Big Bore System
Halliburton’s VersaFlex expandable liner hanger (ELH) system helps operators reduce both risk and capital costs. Designed specifically for the deepwater and subsea markets, the VersaFlex Big Bore system is ideal for complex well conditions. The VersaFlex Big Bore system does not require landing in a pre-determined profile, helping to eliminate complications common to positioning in mudline/casing wellhead profiles.
The system does not require liner-top cement integrity to achieve a liner-top seal upon setting. It incorporates casing-placement flexibility that helps eliminate related liner installation issues, and our elastomeric seal technology is unmatched in the industry. With our ground-breaking clean-form design, the VersaFlex Big Bore system is an all-in-one integral hanger/packer. It has no moving parts, which helps eliminate costly tool failures associated with conventional liner hangers.
CAPEX savings do not end at operations, they continue throughout the life of the well. With its “set and forget” reliability, the redundant leak-proof design helps eliminate sustained casing pressure. Rotation and reciprocation also help ensure the best possible cement placement and cement bond. Surge and ECD risks are greatly reduced with an optimized OD and lack of a profile ring.
One of the biggest payoffs for operators is a cost reduction in materials. Liner overlap is greatly reduced with the VersaFlex Big Bore system because pressure bearing tieback strings are not required. The VersaFlex Big Bore system also minimizes many of the operating steps required to set the liner hanger/packer, compared to conventional systems while virtually eliminating remediation costs.
VersaFlex Big Bore system’s rotating and reciprocation capability during cementing allows for zonal isolation integrity. An ideal solution for extreme well conditions, its high-torque rating permits reaming through downhole cave-ins, kicking-off ledges from previously drilled segments, and drilling new hole sections.
Features
? Simplified installation – operational steps cut in half compared to conventional systems
? Fully integral hanger/packer design
? Minimized potential leak paths
? Designed to hang 13 3/8-in. – 18-in. liners
? Large radial clearance (clean-form design)
Benefits
? Proven reliability
? “Set and forget” – design simplicity helps eliminate risks associated with conventional liner hangers
? Improves wellbore integrity
? Solves issues associated with larger casing strings installed in deepwater or subsea wells
? Holds in tension and compression during the life of the well
? Sets in deviated wellbores
? Improved bypass area for reduced ECDs
Halliburton Installs First VersaFlex Big Bore System in Angola
OVERVIEW
A major deepwater operator had been drilling offshore Angola for several years in an ongoing exploration campaign in two different blocks. Although the operator had supplemental casing adaptors in its stock, it was experiencing nonproductive time (NPT) related to casing hanger issues and needed a reliable solution to allow the hanger to move safely through tight tolerances and casing anomalies. Halliburton was tapped to install its VersaFlex? Big Bore system due to its robust hanger and running tool. The installation was a success, and the liner was set to depth – the first such installation in Angola.
CHALLENGE
The Angola operator was experiencing NPT issues specifically related to supplemental casing adaptors. It was discovered that there were welded restrictions inside the 20-in. casing. This presented concerns, since the liner hanger had to pass through a tight tolerance for more than 671 m (2,200 ft).
SOLUTION
The VersaFlex Big Bore system was a natural fit for this application because the tool provided a liner-top packer and liner hanger in a single trip. The smooth-form exterior allowed the hanger to move safely through tight tolerances and casing anomalies. Additionally, unlike a casing hanger, the system can be set and sealed reliably anywhere in the parent casing, independent of, and without the need for, cement or a landing adapter to seat the hanger. Multiple sealing elements were preferred over the delicate external machined profile of the casing hanger. This provided unprecedented casing placement flexibility, because it is not necessary to hang-off at the wellhead. The robust running tools can withstand more than 100,000 ft/lb of torque, and have the ability to wash, ream, or drill the liner into position.
After thorough pre-job planning and careful examination of the casing between the operator and Halliburton, a VersaFlex Big Bore expandable liner hanger system was installed in 1,805 m (5,922 ft) of water depth from a drillship.
RESULT
The VersaFlex Big Bore system was deployed flawlessly without any safety and service quality issues. Most importantly, there was no NPT during the operation and three days of remediation were potentially avoided, saving the operator a significant amount of money, considering the uncertainties and risks associated with deep water.
With a 97.5 percent reliability performance rating, the VersaFlex Big Bore system helped Halliburton achieve a benchmark for its first installation in Angola’s challenging deepwater environment.
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