New Platforms Design Withstand North Sea Conditions

The pressure to reduce the cost of new developments has never been greater for North Sea operators. The combination of low oil prices, decreased North Sea development opportunities and increased competition from the U.S. shale industry means the industry is being forced to adapt to new ideas.

One development concept that is starting to gain traction is the use of low-cost wellhead platforms for the development of small satellite fields. These are typically newly discovered fields close to an established host platform, which can provide control and power and also carry out fluid processing. Although wellhead platforms have long been a favorite in the shallow waters of the southern North Sea, up until now the preferred option for the development of satellite fields in deeper water has been to use a subsea manifold with a tieback to the host facility. Subsea manifolds are tried, tested and trusted, but WorleyParsons has carried out several studies showing that subsea manifolds don’t necessarily provide the best value solution for a multiple well development. The difficulties and additional costs associated with maintenance and future well intervention operations can all contribute to increased costs over the lifetime of a project.

WorleyParsons has accumulated a reference list of more than 500 installations that are currently operating throughout the world, and its team has combined its experience with ideas borrowed from the shale industry—where standardization and modularization of equipment is the key to low-cost field development. The company has come up with a new concept in wellhead platforms suitable for installation in deeper water and able to withstand North Sea conditions.

The new design uses piled foundations, can be deployed in water depths of up to 120 m (394 ft) and provides space for a maximum of 12 well slots. No accommodation has been provided for personnel, who will gain access for four monthly maintenance visits by vessels equipped with a “walk-to-work” gangway. The platform design includes a 5-tonne crane and sufficient deck space to allow full access for future well intervention. WorleyParsons also has designed the new platform for construction in its covered yard near Stavanger, Norway, with one flat side to permit installation by either barge launch or jackup platform to widen the choice of installation contractor.

The platform is designed with a “design once, build many” approach to capture economies of scale and efficiencies more closely associated with a production line than a North Sea construction yard. The design borrows from the philosophies that WorleyParsons has previously followed in the Persian Gulf and Gulf of Thailand and uses a minimum number of different profiles to reduce procurement and stockholding costs.

Topsides and jacket weights are comparable to more traditional North Sea designs at about 650 tonnes and 3,500 tonnes, respectively, for a 100-m (328-ft) water depth platform, with almost all of the topsides and much of the jacket being identical for any platform regardless of water depth. However, there is scope for significant savings in project schedule by both reducing setup times and by allowing construction to start in parallel with detailed design. The design is so standardized that water depth, seabed conditions and well slot arrangement are the only pieces of information required to completely define an individual platform, further reducing project schedule and minimizing construction risk.

WorleyParsons sees an immediate market for at least 20 lowcost modularized platforms in the Norwegian sector of the North Sea alone and is talking to several operators who have been carrying out studies to assess their viability. They also see applications in U.K. waters, where the upcoming 30th licensing round will be targeting small pool discoveries that will require especially low-cost development schemes.

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New Oil Drilling Technology Will Soon Spark An Explosion Of Oil

Energy stocks have been tearing higher since the election on bets that the Trump administration will relax environmental restrictions and open more federal lands to oil and gas drilling. Crude oil’s staying north of $50 hasn’t hurt, either.

It is up there in part because OPEC threw in the towel and agreed to production limits. Unfortunately for OPEC, those limits don’t apply to US and Canadian shale producers. And the history of OPEC is that they all cheat like crazy, anyway.

There will be no end to oil production

I think it is entirely possible that we will see oil prices climb somewhat further by mid-year, possibly approaching $60, and then pull back as capped US production comes back online. Look at the chart below to see the wide variation among forecasts of major energy analysts working for the big banks.

I also think that this year, we’ll start to see a new pattern: Production could keep rising even as prices fall. Conventional wisdom says that producers stop pumping at some point when it becomes unprofitable, but I think that is about to change.

New technology will lead to greater production and higher profits

If you are an oil producer—or really, any commodity producer—two things can improve your profit margin: higher selling prices for the resource you produce or lower production costs. Some combination of both works as well.

Now, selling prices are mostly outside the producer’s control, though adept hedging can help. Cost reduction is, therefore, the place to concentrate your attention. Back in 2015, I wrote about new drilling techniques and other technology that promised to bring oil and gas production costs significantly lower.

Now, in the last few weeks, people in the business have told me these technologies are moving rapidly toward deployment. They foresee considerably lower drilling and production costs by the end of this year.

I had a confidential briefing recently about some new energy production processes that are coming online in the oil patch. Let me just say that production from an oil well drilled with these new techniques is getting ready to increase substantially.

In some cases, the amount of oil produced per dollar spent on drilling is going to more than double. There are significant chunks of the petroleum-producing parts of the United States where $40 oil will not be a barrier to drilling and new production.

Eventually—in a few years—these techniques will begin to show up in wells around the world, and there will be an explosion of oil. Even as many oilfields dry up, there will be new fields developed from previously unprofitable sources.

This will have massive economic and geopolitical implications

This technology trend means that the current oil price range may well break lower—perhaps this year, but certainly within this decade—without energy companies losing profits.

Not every company will reap the rewards equally, of course; but the industry as a whole is excited. Energy exploration and production is quickly becoming a technology-driven industry with the US as world leader.

If Trump permits construction of more pipelines and natural gas export terminals, we could see North American exports rise considerably in the next few years.

Obviously, over time, a falling energy price will not be good for OPEC or for Russia. Those lower prices will create geopolitical challenges as well as economic ones. I don’t know how it will all shake out. We will likely see some big, energy-driven changes in the world order in the coming decades.

But that is beyond the scope of my crystal ball.

Source: www,forbes.com

Read More → New Oil Drilling Technology Will Soon Spark An Explosion Of Oil

Digitalization Directional Drilling

Super-specification pad-optimal Swiss Army-style walking rigs may generate headlines when it comes to evolution in land drilling, but directional drilling is fast becoming a more accurate indicator of how the sector is evolving as tight formation development enters full field development.

Companies like Baker Hughes, a GE company, have offered sophisticated geo-steering suites combining bits, motors, downhole evaluation and software control to improve ROP for some time. But quietly, and without fanfare, the largest domestic land drilling contractors and their Canadian peers are integrating digital directional drilling capabilities into rig offerings.

The trend accelerated over the last six months when land contractors began purchasing digital directional drilling providers. Acquisitions include Helmerich & Payne IDC’s $100 million purchase of Motive Drilling Technologies Inc. in May, Patterson-UTI Energy Inc.’s $215 million cash and stock purchase of MS Energy Services and Trinidad Drilling Ltd.’s $40 million cash and stock acquisition in August of RigMinder Inc. and its electronic data recorder and bit guidance systems, which integrate the rig and directional drilling tools.

Other drillers, including Nabors Industries Ltd. and Ensign Energy Services Inc., offer directional drilling services and supporting downhole packages that include proprietary mud motors and MWD tools integrated with software to improve directional drilling performance. Nabors, for example, is commercializing a multiple package software suite that includes its recently developed ROCKit directional steering control system.

Meanwhile, Canada’s Precision Drilling aims to “de-man” the directional drilling process via a proprietary directional guidance system that coordinates workflow between the rig’s driller on location and a remote directional driller who oversees several directional drilling projects simultaneously. Precision is using algorithms to convert 14 process and 20 decision points in directional drilling into seven processes and 10 decisions, reducing support crew, time and cost. The system will be fully deployed across Precision’s fleet in 2018.

What’s going on? At the simplest level, it is an opportunity for drilling contractors to capture more revenue per rig in a flat pricing environment. Beyond that, larger drillers are bringing in-house a service that is integral to today’s best practices where precise lateral landing in extended wellbores is as important for boosting hydrocarbon recovery as greater proppant loading.

Digitally enhanced directional drilling integrates software suites, sensors and downhole tools to reduce wellbore tortuosity and generate higher ROP. Digital directional drillers  point to field-tested savings in time and direct costs that are measured in tens of thousands of dollars per well.

Digitalization of directional drilling is disruptive technology. The question is whether it will supplant both personnel and the community of independent service providers.

One other factor promoting the spread of digital directional drilling is that the software is often independent of the rig, allowing smaller contractors to integrate the service into their own rig offerings via third-party access.

Like all wellsite technology, digital directional drilling may require an evolutionary step in perception at the well site that also incorporates specialized human input and flexibility as the best solution for sophisticated problem-solving in a dynamic environment.

Source:Shutterstock.com

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Investment for Offshore Rig

Offshore drilling is a technology-heavy industry, and if you want to invest in companies that work in this space of goods, you want to be familiar with the associated terminology.

Since offshore drilling can take place in unforgiving places, companies need to implement specific boats for specific drilling projects. These ships are among the most technologically advanced man-made structures. Some ships are designed to withstand strong winds and high waves. Others are more suitable for exploratory projects in shallow waters and need to move from one place to another quickly.

Here are the names of some of these pots you can expect to come across as you start investing in offshore drilling companies:

• Barge drilling: The drilling barge is one of the most agile vessels on the market. It is a floating device usually towed by a tug to hit puncture positions. The drilling barge is mainly used in the inland, still shallow waters, such as rivers, lakes and swamps.
• Jack-up rig: The rig jack-up is a hybrid vessel that is part floating barge, part drilling platform. The jack-up drilling rig is towed to the desired position, usually open, shallow waters where its three "legs" are lowered and "jacked" towards the seabed. When the legs are fixed, the drilling platform is raised to the desired levels to allow for safe drilling.
• Submarine Rig: The submersible rig is similar to the rig jack-up, as it is mainly used for shallow water drilling and is fixed to the bottom of the sea.
• Semi-submersible plant: sometimes referred to as a seed, this structure is a stunt of modern technological development. It's like a submersible, except that it has the ability to pierce deep in adverse weather conditions and not forgive. 
• The drilling platform is high and sits on top of a floating structure that is semi-submerged in water (hence the name) and secured by large dowels that can weigh up to 10 tons each.
• Drill Ship: The drilling vessel is essentially a ship with a drilling deck. It is perhaps the most versatile drilling tool as it can easily be sent to remote offshore locations, including deepwater drilling.
• Offshore Oil Platform: When one of the previous vessels discovers a commercially viable offshore oilfield, a company may decide to build a permanent platform to exploit this discovery. Insert the offshore oil platform. These facilities are a spectacle to see and are really from the floating city man. They are staffed, they include homes, and are often equipped with shelter. They are ideal for difficult conditions in deep waters.

Read More → Investment for Offshore Rig

Purpose of Barite or Baryte

In oil and gas drilling

Worldwide, 69–77% of baryte (barite) is used as a weighting agent for drilling fluids in oil and gas exploration to suppress high formation pressures and prevent blowouts. As a well is drilled, the bit passes through various formations, each with different characteristics. The deeper the hole, the more baryte (barite) is needed as a percentage of the total mud mix. An additional benefit of baryte (barite) is that it is non-magnetic and thus does not interfere with magnetic measurements taken in the borehole, either during logging-while-drilling or in separate drill hole logging. Baryte (barite) used for drilling petroleum wells can be black, blue, brown or gray depending on the ore body. The baryte (barite) is finely ground so that at least 97% of the material, by weight, can pass through a 200-mesh (75 μm) screen, and no more than 30%, by weight, can be less than 6 μm diameter. The ground baryte (barite) also must be dense enough so that its specific gravity is 4.2 or greater, soft enough to not damage the bearings of a tricone drill bit, chemically inert, and containing no more than 250 milligrams per kilogram of soluble alkaline salts.[7] In August 2010 API (American Petroleum Institute) published specifications to modify the 4.2 drilling grade standards for baryte (barite) to include 4.1 SG materials.

In oxygen and sulfur isotopic analysis

In the deep ocean, away from continental sources of sediment, pelagic baryte (barite) precipitates and forms a significant amount of the sediments. Since baryte (barite) has oxygen, systematics in the δ18O of these sediments have been used to help constrain paleotemperatures for oceanic crust.

The variations in sulfur isotopes (34S/32S) are being examined in evaporite minerals containing sulfur (ex, baryte (barite)) and carbonate associated sulfates (CAS) to determine past seawater sulfur concentrations which can help identify specific depositonal periods such as anoxic or oxic conditions. The use of sulfur isotope reconstruction is often paired with oxygen when a molecule contains both elements.

Other uses

Baryte (Barite) is used in added-value applications which include filler in paint and plastics, sound reduction in engine compartments, coat of automobile finishes for smoothness and corrosion resistance, friction products for automobiles and trucks, radiation-shielding cement, glass ceramics and medical applications (for example, a barium meal before a contrast CAT scan). Baryte (barite) is supplied in a variety of forms and the price depends on the amount of processing; filler applications commanding higher prices following intense physical processing by grinding and micronising, and there are further premiums for whiteness and brightness and color.It is also used to produce other barium chemicals, notably barium carbonate which is used for the manufacture of LED glass for television and computer screens (historically in cathode ray tubes); and for dielectrics.

Historically baryte (barite) was used for the production of barium hydroxide for sugar refining, and as a white pigment for textiles, paper, and paint

Although baryte (barite) contains a "heavy" metal (barium), it is not a toxic chemical because of its extreme insolubility.

It is also sometimes used as gemstone.

Read More → Purpose of Barite or Baryte

Steerable Downhole Mud Motor - Directional Drilling

Steerable Downhole Mud Motor (SDMM) commonly referred to as Mud Motor or Drilling Motor acts much as a positive displacement motor which provides additional rpm to the drill bit from the flow of drilling fluid (mud).

This drilling motor is far different from an electrical motor in it's working principle and operation.

(A lot of people get confused initially)

Since its introduction, the positive displacement motor has undergone revolutionary changes and improvements. Downhole drilling motors have proven to be successful in the most rigorous of drilling environments. From the time of its inceptions, the mud motors have gone extensive improvements that has enhanced its performance, operational and economical reliability. 

Today there are numerous players in the industry providing mud motors for different operational requirements. Few to name are National Oil Varco (NOV), Schlumberger, Halliburton, Baker Hughes, Weatherford, Cavo, Bico, Jaguar, APS, etc. Different mud motors provided by different companies vary a little from each other but, there basic operating principle remains the same. 

Mud Motors have extensively wide range of applications and few of them are listed below:

Conventional Directional Drilling

Side-Tracking

Performance Drilling

Short/Medium/Ultra-short Radius Wells

Air/Foam or Under-balanced Drilling 

ERD Wells

HP/HT Wells

Coiled Tubing Drilling

Vertical Drilling

Casing Drilling

Milling

Coring

Slim Hole Drilling

Working Principle

Mud motors converts the flow energy of drilling fluid (mud) in rotational motion that's utilized in rotating drill bits at a much higher rpm. 

It's imperative that flow rate can be used to control the rpm of the drill bit as per operational requirements. Flow rates for muds are provided by the mud pumps.

Bit RPM = {Flow rate (in GPM) x RPG (Revolutions Per Gallon)} + Rotary RPM 

Note: 

RPG is defined as the revolutions made by bit box and in turn bit, when one gallon of mud flows through it & is mentioned by the manufacturer for each type of SDMM.

While sliding rotary rpm will be zero.

Parts of SDMM:

Simple classification of SDMM parts can be categorized as: 

Top Sub Options

Power Section

Drive Shaft Assembly

Adjustable Bent Housing Assembly

Bearing Assembly

Bit Box

Top Sub options

Top Sub: 

Top sub is simply a cross over housing at the top end of the motor. The lower connection uses a thread that connects to the upper box of the stator housing.

Dump Sub:

It contains a Dump Valve Assembly. This allows the mud to fill or drain from the drill string while tripping.

To avoid the ingress of solids from the annulus when the pumps are off, it’s normal to run a float sub as close to the motor as possible.

The motor will function perfectly without a dump valve - It can be laid down and replaced by a sub having the same connections or run with the ports blanked-off. 

Failure of the dump valve assembly can cause sometimes serious troubles.

Motor Catch & Rotor Catch Top Subs:

The rotor catch system is designed to retrieve the motor in case of a housing fracture. It will retrieve the motor from the upper stator box connection down to the drill bit. The motor catch system has the additional feature of an integral catch flange within the top sub. It will retrieve the motor from the top sub down to the drill bit.

Power Section

Positive Displacement Motors (commonly called a PDM) are reverse applications of a Moineau pump or screw pump. 

It mainly consists of Rotor & Stator.  

Rotor is chrome-plated alloy steel of spiral-helix shape. 

Stator is a hollow steel housing, lined with a molded-in-place elastomer rubber compound. 

A spiral-shaped cavity is produced in the stator during manufacturing. The rotor is produced with matching lobe profile and similar helical pitch to the stator, but with one lobe less. The rotor can therefore be matched to and inserted inside the stator. When assembled, the rotor and stator form a continuous seal along their matching contact points. Fluid is pumped into the motor’s progressive cavities. The force of the fluid movement causes the shaft to rotate within the stator. Thus, it is a positive displacement motor. The rotational force is then transmitted through the connecting rod and drive shaft to the bit.

  

Stage is the distance measured parallel to the axis between two corresponding points of the same spiral lobe. This distance is commonly referred to as the lead of the stator. A slight interference fit between rotor OD and stator ID controls motor power. 

Mud motors are divided into slow-speed, medium-speed and high-speed types. This is done by changing the pitch of the motor stages, by the number of "lobes" and resultant cavities of the stator. 

The greater the number of lobes, the higher the motor torque and the lower the output RPM. 

Increasing the flow rate through a given power section directly increases the output speed. To increase the output speed of a power section without changing the flow rate, the cavity size is changed. A high speed power section will require a larger fluid inlet area (cavity) to allow more fluid throughput into the cavity.

The torque generated by the power section is proportional to the differential pressure applied across the power section and is independent of fluid flow. Generally, the more weight applied to the bit, the higher the torque needed to keep the bit turning, so the higher the differential pressure across the Power Section.

The maximum recommended differential pressure is limited by the stator elastomer. If pressure increases beyond the limits of the elastomer, the stator elastomer will deform, breaking the cavity seal so the mud flow leaks past the rotor and rotation stops – this is commonly known as a stalled motor.

Drive Shaft Assembly

The drive shaft assembly converts the eccentric motion of the rotor into concentric rotation for the bearing assembly via a connecting rod attached to the lower end of the rotor. It transmits the torque and rotational speed from the rotor to the drive shaft and bit. Universal joints convert the eccentric motion of the rotor into concentric motion at the drive shaft. 

It also accommodates any angle set on the adjustable bent housing (or fixed bend housing) and carries the thrust load from the rotor caused by the pressure drop across the power section.

Adjustable Bent Housing

ABH connects stator to the bearing assembly and also houses drive shaft assembly. It has a field adjustable angle-setting to produce a wide range of build rates.

Angle setting may be set to zero for vertical drilling or may be set to any other angle setting as desired. Once the angle is set for the mud motor, it can't be changed when it's down hole and has to be pulled out of the hole to change the angle-setting.

Higher rotary rpm could be used at low angle-setting as compared to a high angle-setting.

Drilling at a higher rotary rpm provides a drill bit with more torsional force provided by the entire rotating drill string as compared to the torsional force provided alone by the mud motor.

(That's the reason why ROP in rotary mode > ROP in sliding mode)

Bearing Assembly

The drive shaft assembly is supported within the bearing housing by radial and axial thrust bearings. It transmits the rotation of the drive shaft assembly to the drill bit and the compressive thrust load created by the weight of the collars and drill string to the rotating bit box & supports the radial and bending loads developed while directional drilling.  

It also carries the tensile off-bottom thrust load produced by the pressure drops across the rotor and the drill bit, as well as any load caused during back reaming. The high capacity radial bearings readily withstand side loads caused by drilling with a deflection device or uneven cutting action along the drill bit periphery. The tungsten carbide radial bearings and angular contact bearing section supports the radial loads along the full length of the bearing assembly, creating a very stiff, strong assembly

Types of Bearing Assembly-

Mud Lubricated Bearing Assembly

Oil Sealed Bearing Assembly

Mud Lubricated Bearing Assembly regulate the flow of mud through the bearing assembly. This diverted mud (usually 4 - 10%) is used to cool and lubricate the shaft, radial and thrust bearings. It exits to the annulus directly above the bit sub. The exact percentage of mud diverted is determined by the condition of the bearings and the pressure drop across the bit. Mud lubricated bearing assemblies can be used in the hottest holes with the lowest aniline point drilling fluids, as there are no elastomeric seals.

Oil Sealed Bearing Assembly is an alternative to the mud-lubricated bearing. A sealed bearing would be recommended where corrosive muds are used, where a lot of LCM of various sizes is pumped or where there is a requirement for a very low pressure drop across the bit (Pbit).

Bit Sub

At Bit sub the drill bit is make up with the motor and it's the only moving external part of the motor.

  

Note: 

In addition to above, different manufacturers can have more or less parts.

The operating conditions and parameters for the mud motors may vary for different manufacturers.

Read More → Steerable Downhole Mud Motor - Directional Drilling

Intangible drilling costs - IDC

Costs to develop an oil well or gas for the elements that are not part of the final work well. Costs of intangible (IDC) including all expenses incurred by an incidental operator required the drilling and preparation of wells for oil and gas production, as the survey work, land clearing, drainage, wages, fuel, repairs, supplies and so on. In general, expenses are classified as IDC if they have no salvage value. Since IDC include all real and actual expenses, except for the drilling equipment, the word "immaterial" is something of a misnomer.

Our drillingknowledge blog calls - 'intangible drilling costs - IDC'

The IDC deduction was authorized in the United States since 1913 in order to attract investment capital for business at high risk for oil and gas exploration. If a taxpayer makes an election to IDC expenses, it shall be deducted the amount of the IDC in the tax period in which it was paid or incurred.

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Conclusion on the processing of oil

The oil must undergo many changes to be exploitable in the context of a specific use. These transformations involve multiple energy consumption, little known today (no doubt the oil industry have information on this issue). In the end, the multitude of products can be used in various ways (fuel, fuel, petrochemical, plastics, etc.).. 

These byproducts are sometimes directly recyclable (gasoline, diesel, etc.). sometimes they will suffer from further processing to be usable, some are even-products, which have no real opportunities. 

The tendency is to a maximum value of by-products, and the proportion of products derived is relatively fixed, Indutries oil must seek additional outlets for products produced in over-quantity. For example, the French fleet dieselisation pushes the quantities of products for which we must be sure the application or to find new markets.

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EOR - Enhanced Oil Recovery

When the reservoir pressure is insufficient, we proceed to the injection of fluid (s) to force oil to rise. These fluids may be gas (one of the deposit, or liquefied petroleum gas), or water.

Techniques more advanced (and more energy-intensive), such as thermal methods or fluid drive missible, allow to exploit the deposits difficult.

The thermal method involves heating the oil to the fluid (that is to say, reduce its viscosity). The heat comes from the injection of steam or underground combustion.

The fluid drive missible is performed using carbon dioxide or liquefied petroleum gas, lighter. Finally, chemical methods attempt to limit the capillary that holds the oil in the rocks. This is done using polymers or micro-emulsions of oil, water, alcohols and surfactants.

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State of the World's Oil Reserves

A simplified figure and relatively speaking: a cube of 7 kilometers from the side, half empty (or half full, it depends), with a leak rate equivalent to the Rhone is the current state of reserves and world oil consumption.

Proven reserves are generally estimated at between 140 and 160 Gt, or 1,050 to 1,200 Gbl. But taking into account technological advances and a recovery rate above 30%, the reserves could reach 266 Gt (or 1'996 GBL). The truth is that the reserves are not well known, and that in addition to proven reserves, it is quite inappropriate to make hypothetical assumptions about the probable reserves and ultimate.

Fairly coarse (and varies according to findings nouvaux oilfields), proven reserves are geographically distributed as follows:

• 55-60% in the Middle East;
• 15-18% in North America;
• 7-8% in Central and South America;
• 6-7% in Eastern Europe and Former Soviet Union;
• 6-8% in Africa;
• 3-5% in Asia and Oceania;
• 1-2% (!) In Western Europe;

I'll let you calculate how many tons or barrels this is by geographic area.

The countries of OPEC account for approximately 75-80% of total world proven reserves. Several sources say, however, that the state reserves of many countries been an overestimate: these optimistic data are primarily used to sit supremacy and economic influence of the major producing countries.

The rise in oil prices led to interest in deposits unconventional oil , such as oil sands, whose operation is known as energy-intensive, highly polluting, and catastrophic for the environment (despite some methods that allow to avoid the creation of open pits).

Global warming also affects some plan to use: the melting of arctic ice led some companies (such as Arctic Oil & Gas Corp) interest in the exploitation of hitherto inaccessible deposits.

Finally, the exploitation of new (types of) deposits appears to be the preferred track to generate more wealth to the detriment of the fight against global warming and more generally the protection of the environment. Or how to cut ever more ardently the branch on which we sit ...

Read More → State of the World's Oil Reserves