Category Archives: Drilling fluid
TOTAL E&P Australia (Total) has signed up to use AGR’s Riserless Mud Recovery (RMR®) system. The contract is for two exploration wells to be drilled over the next year in the Browse Basin off North West Australia.
Bernt Eikemo, AGR’s Vice President of the Enhanced Drilling Solutions (EDS) division (Asia Pacific), said: “AGR is delighted to be part of Total’s drilling team during the forthcoming exploration campaign. We hope that this is the start of a long, successful relationship with Total E&P Australia.”
He added: “Our previous experiences with several operators in the Browse Basin and the North West Shelf have shown that unconsolidated sand formations become much more benign when drilled with RMR® using a proper mud system.”
RMR® has been used by Total on several other projects internationally but this is the first time that the operator has used the system in Australia.
The main reason for using RMR® on these wells is to be able to drill through the unconsolidated sands of the Grebe Formation. It is renowned for stuck-pipe problems when drilling riserless using seawater and sweeps.
RMR® (system example attached) enables the use of weighted, engineered mud in the top-hole section. All mud and cuttings are returned to the rig with no discharge to the seabed. The top-hole section can be drilled more safely, quickly and with less impact on the environment.
RMR®, together with its sister technology the Cutting Transportation System (CTS™), has been deployed on more than 500 wells worldwide to date.
Jan 18, 2011 Marie Brannon
Before Baroid offered commercial mud testing services to the petroleum industry, mud men experimented with various techniques to test drilling fluids
Drilling mud was first tested for commercial purposes by the Baroid Division of the National Lead Company in 1929 in Houston, Texas. They also produced the first commercial mud testing products. Before 1929 drillers dug clay out of any nearby bank or used native earth.
From Mud Buckets to Precise Instrumentation
Between the discovery of Spindletop in 1901 and the appearance of Baroid in 1928, there were nearly three decades of rotary drilling. The old-timers tested their mud by “rule of thumb”. They knew two kinds of mud: thick and thin. New workers learned from the veterans how to pick up a handful and determine just the right thickness needed.
By 1913, drillers were aware of gelation. Since the well was often shut down for lunch break or other delays, the mud would gel during the break, and the workers called this “getting logy”. They discovered that if they started the pumps occasionally during shutdowns, it would keep the circulation free.
They also could tell if the mud was gas-cut by observing the froth or foam in the mud pit. During the winter of 1913, the Bureau of Mines conducted the first engineering studies by sending J.A. Pollard and A.G. Heggem to Oklahoma oil fields to test the properties of drilling mud. The resulting report was published in 1916 and holds the distinction of being the first ever technical bulletin on the subject.
In early field tests, samples of clay were mixed by hand in an ordinary wash basin. Circulation tests were made by adding two quarts of red paint into the drill pipe at the surface and timing the period required for the color to appear in the mud pit. One record of such a test provided a time of two hours and 33 minutes for circulation in a hole that was slightly more than 3,300 feet deep.
Heavy Drilling Muds
Early on, researchers discovered that all “thick” muds did not weigh the same. It was believed that heavier muds could be useful in drilling against gas pressures, so the California Department of Petroleum and Gas conducted some tests with five-quart containers.
These were calibrated so that one gallon fluid would fill exactly 4/5 of the inside and was marked with a ridge. They also had scales that would accurately record weights up to 30 pounds showing a difference in just one ounce. This was the prototype for the first piece of mud-testing equipment ever produced, by Baroid in 1929.
Between 1917 and 1922, when college degrees were first awarded in the field of Petroleum Engineering, mud testing began to receive serious attention from both scholars and manufacturers. The specific gravity (weight) of drilling mud was tested using oilfield hydrometers that were adapted for this use.
Several different terms and scales were used to express results, including pounds per cubic foot or pounds per gallon. They also developed a specific gravity scale. In 1921, petroleum geologist Dorsey Hager said “Mud-laden fluid has a specific gravity of from 1.15 to 1.3, and weighs from 72 to 81 pounds, as against 62.5 pounds per cubic foot of water. It exerts a pressure of 0.499 to 0.564 pounds per square inch, as against 0.434 for pure water”.
Gradually, oil men realized that not only weight but viscosity should be considered. Standard Oil Company of California engineers used a McMichael viscometer to test mud. It measured the friction of a liquid against a disc suspended from a calibrated wire, in a cup of liquid which was rotating at a constant speed. The ancestor of the Marsh funnel was the Engler viscometer, originally developed by Dr. Charles Engler in Germany in 1884 for use in the railroad industry.
Testing the Viscosity of Drilling Mud
Various rotary viscometers were also in use to test the viscosity of oil. The Napier and Cockrell types were early predecessors of the Stormer, Fann and Baroid devices. Napier and Cockrell apparatus was in use for more than fifty years and utilized paddle wheels revolving in oil or other fluids. There is no record that these were used to test mud, but they were described in oil engineering texts of the time and may have been used in this manner.
In 1930, Baroid introduced the first mud bucket and scale as a test instrument. These were given away as free samples, but by 1934 they began to equip vehicles for field testing. These cars carried a Marsh funnel, a Stormer viscometer, a portable mixer, an electric hot plate, screens, graduates, a Mudwate Hydrometer, a Wulff pH tester, a balance, and a mortar and pestle. Around 1936 they added a mud balance that had been developed by Phil Jones of the Union Oil Company of California.
“The History of Mud Testing”, Baroid News Bulletin October 1960
Shale Shakers and Drilling Fluid Systems, by American Association of Drilling Engineers, Gulf Publishing Company, 1999
Oil Field Practice, by Dorsey Hager, McGraw-Hill, 1921
Read more at Suite101: The History of Mud Testing
An ambitious exploratory well project has entered the record books – with AGR’s Riserless Mud Recovery (RMR™) system from their Enhanced Drilling Solutions division helping to make it possible.
Woodside called a total section depth of 1,905m (6,250ft) on the Tidepole East-1 exploration well off Western Australia. It was the first time that Woodside had used the Casing While Drilling (CWD) method on one of its wells and the depth reached sets a new world record for the technique.
RMR™ enabled Woodside to use the type of drilling mud needed to maximize the wellbore smearing effect that CWD provides, which helps keep the wellbore stable.
The system allows top-holes to be drilled using weighted mud, with fluid and cuttings returned to the rig and no discharge. It is also able to supply the low pump rates and good hole-cleaning capability required to drill efficiently, despite the relatively narrow annulus that was a feature of this project.
Thanks to RMR™ and the casing being run during the drilling process, there were no losses to the formation during that stage – an all-too-common occurrence with conventional drilling method.
AGR’s ingenuity solves the challenge
Standard internal or external wellhead adapters could not be used on this project for the RMR’s™ Suction Module (SMO) without extensive modification to the Permanent Guide Base, or without causing difficulties when it came to landing the High Pressure Well Head (HPWH) on the Low Pressure Well Head (LPWH) later on in the operation.
AGR’s ingenuity provided the solution, with an internal adapter being devised that could be split. This meant that the casing could be drilled down with the SMO in place.
General Manager EDS Asia Pacific, Bernt Eikemo, said: “When it was time for the HPWH to be landed on the LPWH, the SMO could simply be lifted off the LPWH using two ‘tugger’ winches on the rig, with an ROV performing the split.
“This of course has never been done before but, with a simple design and good communication with the ROV Company, it proved to be a great solution and it took next to no time for the ROV to release the locking pins and split the adapter.”
The operation went smoothly, with an impressive Rate of Penetration (ROP) achieved of some 60m (197ft) per hour. Bernt added: “This would have been impressive even with conventional drilling. To be able to drill these kinds of wells and others in a quick, simple way like this can potentially create great savings for operators.
“Working within areas with challenging geotechnical conditions, a proper mud system and the ability to have full returns are vital for success. RMR™ is perfect for this application.”
AGR recently surpassed the 500-well landmark for its Cutting Transportation System (CTSTM) and RMR™. Next year will see the first deployment of the company’s EC-Drill™ Managed Pressure Drilling system.
- AGR Signs Deal to Supply RMR to Woodside for Use on Australia’s North West Shelf
- UK: Aquaterra Wins Drilling Riser Contract
- Norway: Eni Norge Chooses AGR ‘s Technology for Multi-Well Projects in Barents and Norwegian Sea
- Norway: AGR’s Drilling Technology Break Through 500 Wells Milestone
- Norway: NPD Announces Oil Discovery East of Ula Field
- Milestone Achievement for AGR’s Drilling Technology in Chirag Field, Azerbaijan (mb50.wordpress.com)
- USA: Aker Solutions to Open Hi-Tech Drilling Equipment Simulator in – Houston (mb50.wordpress.com)
Cairn Energy PLC, the Edinburgh-based oil and gas exploration and production company, has successfully deployed Centek’s Itsfu Auto Fill Sub in drilling operations in its 2011 Greenland Drilling campaign. The Itsfu provides controlled drill string filling in one third of the time of alternative methods and prevents uncontrolled, hazardous spillage of well drilling fluids onto the rig floor.
“After learning how the Itsfu works, we are now able to fill 10 stands of 5 7/8″ TT585 connection string in around three minutes,” said John Boyle, Drilling Manager, with Cairn Energy. “This saves both time and ensures the immediate area of the rotary table remains clean compared with conventional filling practices.”
Around every 1,000 feet of running in, the drill string must be filled with fluid to equalize the pressure inside and outside the pipe to avoid it collapsing and to balance the well. The filling process interrupts running in, so speed is very important.
Every 10 stands the Itsfu is made up to the drillpipe by means of the integral swivel and the charge pump is started. The gooseneck outlet is automatically closed by a plastic disc to prevent air entering, and the closed-system drillpipe can now be filled in around one third the time of conventional methods. Once the drill pipe is full, the plastic disc comes free, discharging fluid from the gooseneck as a tell-tale. The mud pump is switched off, and with no pressure or air present, the Itsful fill-up tool can be readily removed by hand from the drillstring, without fluid spurting, and hoisted back to its storage area.
“The Itsfu offers real savings of time as it minimises spillages and cleaning up,” said Cliff Berry, Sales and Marketing Manager at Centek Limited. “Also because it screws into the drill pipe at the rotary table rather than by disconnecting the top-drive, the next pipe stand can be made ready while drill string filling is in progress.”
The Itsfu is drill-team friendly and as simple to install as a circulating sub. In addition, as the top drive is not involved in filling, there is no danger of damaging the top drive saver sub threads and the top drive is also available if needed in the open hole.
The Itsfu is available to drilling teams now and can be rented on a daily basis.
- Cairn draws a blank at second Arctic well (guardian.co.uk)
- Cairn Energy setback in Greenland (bbc.co.uk)
- Cairn Energy stays optimistic with Arctic drilling (cbc.ca)
Blue Dolphin and HOS Centerline
Published: Mar 1, 2010
When Hornbeck Offshore Services Inc. introduced its 370-ft (113-m) HOS Centerline last year, it not only gave the Gulf of Mexico the world’s largest support vessel, but also one designed to transport everything from drilling fluid to crude oil. With a more than 8,000-dwt (7,258-metric ton) capacity, the Centerline brings multi-purpose support vessels to an entirely new dimension. Not only is the triple-certified newbuild designed to transport supplies for drilling and production, it can be “flipped over” in two to three days and work as a crude oil tanker, says Todd M. Hornbeck, chairman, president and CEO of the Covington, Louisiana-based company that also operates the HOS Port in Port Fourchon. What’s more, Hornbeck says the newest entry to the company’s global fleet also is fully certified to haul hazardous wastes.
“It’s the only time in the world this has been done,” he says of his new support vessel/tanker combination. A sister-vessel, the HOS Strongline, was expected to join the Hornbeck fleet in February and is destined to receive the same regulatory pedigree.
The HOS Centerline is not only the world’s largest multi-purpose supply vessel, it also is the most versatile, says Hornbeck.
Hornbeck says the uniquely engineered vessels can transport more than 30,000 bbl of liquid drilling mud and fuel. The vessels’ 400 kW of available propulsion, power, and DP-2 capability allows it to work safely in sea and weather conditions that keep smaller vessels in port. The design of the vessel reduces fuel consumption in half, he adds.
“These vessels really provide a wider weather window, and they are equipped and designed to safely transfer cargo in high seas,” he says. “They really give us a cradle-to-grave approach to serving our customers, from spud to production.”
The HOS 370-class cargo deck is 240 ft x 58 ft (1,287 sq m) and is complemented by an additional 30 ft x 58 ft (9 x 18 m) of covered deck space, which is unprecedented. The large deck and living quarters for 78 crew members also makes the Centerline functional for subsea construction.
While the commissioning of the Centerline, gives Hornbeck 85 vessels working worldwide, he says the company will continue to focus on the Gulf of Mexico.
“Any place we look at first has to pass the smell test and convince us it is a better place to be than in the Gulf of Mexico.”
- USA: Harvey Gulf BOD Approves Construction of LNG-Fueled Offshore Supply Vessels (mb50.wordpress.com)
- Westshore Shipbrokers: Ultra-Deepwater, What is Next for the Shipowner? (Brazil) (mb50.wordpress.com)
- Westshore Shipbrokers: A Closer Look at Vessel Scrapping and Attrition in the OSV Market (mb50.wordpress.com)
- Re-inventing subsea intervention to keep economics above water (mb50.wordpress.com)