TORXS saves a well Baker Hughes has introduced an expandable liner hanger system that the company says is the only system of its type that is installed and released prior to a cement job, eliminating the risk of running tools becoming fixed in place during cementing. The system has been used to recover an offshore well after the customer had already decided to P&A the well.
There had been continued fluid loss and fluid level around 4265ft during drilling, so the client needed to perform three sidetracks. The customer considered P&A. Baker Hughes instead suggested a liner drilling solution, with the client choosing the 7 x 95/8in TORXS expandable liner system and an 81/2in EZCase bit to drill and case the problematic section. The client wanted to drill the 131ft length of 81/2in section from 10,597ft to 10,728ft and case and isolate the troublesome zone. It also wanted to switch from oilbased mud to water-based mud to continue the next section.
Baker Hughes said its liner system drilled a 152.5ft length of 81/2in section to 10,748ft, with 62.3ft of that length drilled with complete lost circulation, saving the well. The system averaged 11.7ft ROP at the transition zone and 9.4ft/hr with complete lost circulation, weight on bit (WOB) of 6 tons and 333gal/min. Additionally, the liner hanger system worked under 6000ft-lb to 18,000ft-lb torque, 80-90rpm and internal pressure from 500-2000psi. No other systems can perform under these conditions, the service company claims, adding that it drilled the hole, set the liner, and set the liner top packer in one trip. After the hole was drilled and cased, the liner was set and the annulus was sealed. The liner drilling running tools were pulled.
The 61/8in section was drilled and completed with Equalizer inflow control devices and REPacker reactive element packers. According to Baker Hughes, TORXS Expandable Liner System and EZCase Bit saved $7.5 million on the client's offshore well, in addition to the liner system preventing the P&A of the well.
The TORXS system can be used in deepwater, subsalt plays, deviated wells, extended-reach wells and monobore completions, which Baker Hughes says makes it available for more applications than other liner hanger systems.
The TORXS system offers an advanced torsion capability that allows the casing to be worked to depth in challenging or depleted formations. According to the service company, the TORXS system enables seamless, one-trip, two-stage hanger and packer setting for cemented liner applications. Setting the packer independently mitigates the risk of becoming stuck in wet cement. There is also no need to add retarders that compromise the cement formulation or extend the cement pumping time. Optimizing the cementing job extends the life of the well and reduces the potential for future remediation work.
Bit saves time
A new Varel bit saved trip and rig time on a central North Sea well. The challenge was to drill a 121/4in section from the Paleocene, through the Chalks to the Lower Cretaceous formations in a single run in 350ft of water.
Varel supplied its 121/4in six-bladed PDC bit equipped with 13mm x 19mm latest generation, oval-shaped Vulcan class cutters for maximum abrasion resistance. The drill bit (pictured) was also optimized with engineered hydraulics using six jets dedicated to the six blades including three central angled jets for cuttings evacuation.
The 121/4in VB613PDGX drilled the entire planned interval from casing shoe to Lower Cretaceous in a single run. This was the first time this had been achieved in this field, as other operations normally required two drill bits, according to Varel. The bit was also graded 3-2-BT-N-X-I-WT-TD, which is better than typical offset runs despite drilling further into the geological sequence than its predecessors.
Along with eliminating a bit trip, the bit drilled at a fast ROP of 58ft/hr, compared to the average ROP offset from four wells which showed 40ft/hr through similar formations, Varel said. The company estimates this saved the operator $370,000 based on a calculation of rig time and drill bit costs.
The latest addition to Varel's roller cone drill bits lineup has saved a customer trip time and rig time. The 171/2in HR04DJMRSV drill bit was used in well 205/21, West of Shetland on the UK continental shelf. The bit was selected as the first in a two-bit strategy, with the goal being to drill the first 1300ft from the casing point through the pyrite-rich Balder formation and then changed out for a Varel Steel Body VTD619SX PDC bit to drill the rest of the way to 5446ft MD using a Sperry motor with 1.15° bend and up to 260rpm.
The well was vertical and drilling used a water-based mud system. The well encountered the Balder, Vaila, Sullom and Jorsalfarre formations. The Balder formation contained a high concentration of pyrite, necessitating the need to run a tungsten carbide insert roller cone bit product.
On reaching the 1300ft goal using the 171/2in HR04DJMRSV and with ROPs above expectation, the customer decided not to trip and continued drilling using the 171/2in HR04DJMRSV bit to the planned depth of 5446ft for the 171/2in section. The bit ‘performed very well and achieved all customer requirements and with excellent footage achieved and savings in rig costs', Varel said. The IADC dull grade was 0.1.WT.G EFF.IN.NO.TD.
Varel has commercially launched the new Higher Roller series roller cone drill bits, which range from 143/4in to 181/2in. They are sealed roller bearing designs with either mill tooth or tungsten carbide insert cutting structures.
This series responds to increasing demands on larger diameter roller cone drill bits that are being applied with greater WOB and higher rotations per minute than ever before. Varel bit designers worked to tailor specific cutting structure designs to match the challenging operating requirements and parameters directional and rotary steerable drilling require.
Based on the proven High Energy technology, this addition to the roller cone product line includes the company's patented conical seal geometry technology along with a new, larger lubricant reservoir, which allows High Roller bits to support longer bit life and increasingly demanding applications.
The cutting structure has a high cone offset and larger diameter premium bearing configuration high projection chisel inserts to deliver aggressive cutting action. Centre jet hydraulics are in place to clean the cutting structure and ensure efficient transport of bit cuttings to the annulus. Bit gauge protection features include diamond backrow protection, abrasion resistance, hardmetal shirttail protection and rounded dome abrasionprotection, inserts for both protection and bit stabilisation.
Onsite geology characterization
An automated drill cuttings analysis system has characterized carbonate and clastic geological sequences and reservoirs offshore Qatar. FEI's Natural Resources Business Unit's QEMScan WellSite system was used in field tests by Maersk Oil and Qatar Petroleum at a jackup drilling offshore Qatar.
Information from the system was used to help offshore geologists make onsite drilling decisions, FEI said. QEMScan WellSite system provides automated, quantitative mineralogical, lithological and textural analysis of drill cuttings from oil and gas wells. In the field test offshore Qatar, it was used to characterize the carbonate and clastic geological sequences and reservoirs between June and September 2011.
‘The system endured large temperature variations, humidity, and vibrations on the jackup rig, yet the QEMScan WellSite system was reliable,' said Lewis Affleck, managing director, Maersk Oil Qatar.
He said the system's automated analysis and work flow delivered ‘unbiased, quantitative characterization of drill cuttings in less than an hour from sample collection. Getting higherquality information from drill cuttings helped us to make on-site mineralogy determination with greater confidence, supporting the porosity evaluation, and provided valuable data for post-drilling analysis.' Further, Affleck said, ‘we see potential for its use in deepwater drilling operation, especially in complex mineralogical settings.'
The QEMScan WellSite analysis solution uses scanning electron microscopy and x-ray energy dispersive spectrometry in a streamlined sample preparation and analysis workflow to deliver quantitative, consistent, statistically-valid analyses of the mineralogy, texture and lithology of each cuttings sample, FEI said.
The field test was the system's first application on an offshore rig. OE
|Light bubbles A new glass bubbles offering reduces the risks of sampling in oil & gas cementing that are typically associated with cenospheres. 3M said its Glass Bubbles G65 are a lightweight alternative to cenospheres. The company said the engineered hollow glass microspheres provide petroleum engineers with a consistent source of supply as well as performance reliability in low density cementing.|
3M said it believes the product consistency of G65 will help to increase confidence by reducing some of the risks associated with cenospheres and are expected to provide increased reliability for cementing in demanding applications.
The glass bubbles offer a high strength-todensity ratio and are designed to be lightweight with a high compressive strength for processing survival, the company said. The density of G65 is 0.65g/cc (kg/m3) compared to commercially available cenospheres, which range anywhere from 0.65-0.9g/cc depending upon source of supply.
Therese Tokles, new product manager at 3M, said G65 performs comparably to cenospheres.
3M's glass bubbles line includes products with a variety of sizes, strengths and densities. 3M intends to continue pre-production of G65 through 1H 2012 and then make them more widely available in the summer of 2012.
Picture this A streamlined version of a ToughPIX camera is helping engineers ensure oilfield equipment and systems are running efficiently and safely. CorDEX Instruments' ToughPIX 2303XP camera is more streamlined than its predecessor and captures still and moving images in AVI format of up to 10 mega pixels. Encased in aluminum with an ultrabright display protected by armored glass, the camera is designed for harsh environments, where traditional digital cameras are not permitted. |
Photography and documenting images for surveys and reports is an everyday activity. The ToughPIX 2303 XP camera is ATEX and American CSA certified to take images within Zone 1 IIC T4 and Class 1 Division I B, C, D hazardous areas.
Weatherford's mechanised systems engineer Michael Wilson regularly uses the camera on the job in the North Sea to capture images to help him ensure oilfield equipment and work systems are running efficiently and safely. He carries out preinstallation surveys, which require highquality photographic coverage to show insitu working environments and how operations are functioning. ‘It is necessary to back up surveys and reports with photographic evidence to show machinery working in complex systems and running smoothly,' he said. Wilson deals with pressure vessels, pumps, control systems, boilers, heat exchangers, piping and all things mechanical required to get his job done to ensure the integrity of company assets.
The camera has ‘cut out the requirement for hot permits and reduced timeconsuming paper work. Offshore you will simply not be given a permit to use a camera outside of the accommodation module unless it is for a specific workrelated activity,' he said.
With traditional digital cameras the battery is a source of ignition in a zone 1 or 2 area and the flash can set off the UV flame detectors, which could lead to fire & gas system activation so a gas monitor must be carried at all times and the flash taped over.
The camera has 8GB memory, an LCD screen and an inbuilt safety flash for use in lowlight areas.
CorDEX Instruments has also developed CAMS – CorDEX Asset Management Software – a desktop package that boosts the capabilities of ToughPIX 2300 XP Series cameras and is included as a complimentary ‘addon' package for customers.
CAMS allows users to organize and manage information and images taken in the field with the ToughPIX 2300 XP Series. It can generate reports and quickly manipulate images downloaded onto the system. Users can simply download images, edit then instantly annotate to produce reports.