Technology Roundtable: Drill Pipe & Ancillary Products
Bruno Lefevre: VAM Drilling
Regional Marketing and Technical Support Manager, Europe, Africa & CIS
Nobuhide Sato: TenarisNKKTubes
Drill Pipe business head, Product Design & Quality Control department.
Alexey Viktorovich Emelyanov: TMK
Deputy General Director for Technical Sales Support and Quality Control
Alexey Vakhrushev: Aquatic Engineering
Application Engineering and Standardization Manager
Jason Arnoldy: Arnco Technology
Vice President, Development
John Postle: Postle Industries
President
Felix Kukhol: NOV Tuboscope
Pipe Coating Sales Manager
Colin W. Rumsey: Bestolife Corporation
Representative: Europe / Russia / UK
Peter Farman: Jet-Lube
Oilfield Sales Manager
In this issues technology roundtable feature, ROGTEC looks at the latest technology advancements being offered from drill pipe manufacturers from around the world. In an expansion to our normal format, we also include opinions from some of the ancillary products used in conjunction with drill pipe, including pipe thread compound, internal plastic coatings and hardbanding.
PIPE MANUFACTURERS
1. What advantages do premium pipes have over standard API / GOST pipes and their benefits for drilling contractors and operators?
VAM Drilling (Vallourec Group): Advantages of premium steel pipe as compared to API or GOST pipes include:
» Double shoulder connection (such as VAM EIS, VAM EXPRESS)
» Higher torsional strength
» Longer running life
» Better repair rate
» More tool joint re-cuts possible due to longer tong space
» Better fatigue resistance due to longer internal upsets
» Additional safety margins
» Better toughness (impact test) when using NS1 or DS1 specifications or special grades (VM-150, VM 135 DP-LT etc)
Benefits for drilling contractors and operators include the reduction of non-productive time and the increased efficiency of drilling parameters. Using premium pipe will save you time & money.
Tenaris: Premium pipes have several advantages over standard pipes. When operating in very low-temperature environments, for example, they can resist forces of 80 Joules at minus 40 degrees Celsius. Proprietary steel grades allow for drill pipe that is more resistant (High Strength) or better equipped to avoid corrosion (Sour Service). Additionally, tool joints with double shoulder (such as Tenaris’s DSTJTM and Wedge Series 500TM tool joints) provide operators and contractors with higher levels of torque resistance. Longer tool joints also extend the re-cut capability of drill pipe, thereby prolonging their lifetime. And having equal internal diameter for the pin and box ends of a joint produces bores with smoother hydraulic flow characteristics. In general, premium pipe will afford greater durability and reduced repair rates than API drill pipe.
TMK: A considerable portion of cost savings resulting from the use of improved drill pipes is achieved by extending their useful life compared to standard GOST or API drill pipes. The application of special technical solutions in materials, design, and technology of improved drill pipe production claim to considerably decrease their consumption per meter, to improve hydrodynamic, energy, time indicators of drilling, and to decrease the risks of complications during drilling, construction, and further operation of wells.
Aquatic: Before answering your question, I would like to point out that Aquatic Company, which I represent, manufactures aluminium drill pipes (ADP), which are different both from premium and standard API/GOST steel pipes. The difference relates mostly to their performance properties, while their configuration and handling procedures are most alike with standard steel drill pipes. That is why my answers will mostly be related with ADP.
ADP are twice lighter, while being relatively strong. They can increase the reach of existing rigs, reduce load and torque, as their weight in air is only a half of the weight of similar steel pipes. When exposed in drilling mud they can lose 35-50% of their weight in air, compared to 13-21% for steel pipes. Their application can reduce transportation costs and decrease the wear of rig handling equipment. Aluminium drill pipes also can replace special sour service drill pipe in wells with H2S or CO2, as aluminium is almost neutral to these corrosive agents. Tool joints for sour service ADP are made of special corrosion resistant steels. Inclusion of ADP in a string can lower the rate of vibrations going from the bit to the rig. The stress appearing in pipe walls when ADP is bent in a dogleg is almost three times less, compared to steel pipe, just because aluminium has different material properties. Thus ADP are suitable for drilling sidetracks with higher deviation rates. Other advantages can be mentioned, but it’s a long talk, usually it takes me an hour to run through all advantages of aluminium drill pipes.
2. What factors should contractors or operators consider before selecting their drill string?
VAM Drilling (Vallourec Group): There are numerous factors that must be taken into account by contractors and operators when selecting a drill string. It is imperative that each drill string composition be adapted to specific well design. If a well is deviated, for instance, it is better to use premium pipe with double shoulder connections rather than API in order to improve torque and rate of penetration. In Extended Reach Wells, on the other hand, the use of high strength material is strongly recommended in order to improve tension capacity. Finally, for Sour Service environments, it is imperative that appropriate Sour Service Grades are chosen in order to reduce the risk of Sulfide Stress Cracking. Taking specific well parameters into consideration guarantees a successful drilling program.
Tenaris: Operators will need to pay close attention to multiple technical aspects, which will vary depending on the type of well to be drilled. For horizontal wells, the use of a high-torque, double-shouldered connection is imperative. For extended-reach and deep water wells, in addition to high-torque, double-shouldered connections, it’s essential that the drill pipe is made of a highly strong material to increase tension capacity. In wells with a high concentration of H2S gas, the use of Sour Service drill pipe is recommended in order to avoid sulfide stress cracking failures.
TMK: The following factors affecting the composition of, and the load on the drill pipe string need to be considered for the proper selection of the design of improved drill pipes:
» well type – oil, gas, geological survey;
» fields – onshore or coastal shelf (from fixed or floating drill units);
» well profile – vertical, directed, horizontal, S-shaped;
» process operations – drilling, core recovery, bellying, reaming, borehole calibration, lowering casing parts on drill pipes, drilling out cement plugs (including those inside the casing);
» drilling methods – rotary method with the use of bottom-hole motors (electric drills), combined method;
» risk of possible drill pipe contact with a highly aggressive/corrosive (containing hydrogen sulfide, in particular) environment;
» operating conditions with high or abnormally low temperature conditions of pipe storage and manipulation.
Aquatic: Well trajectory, drilling parameters, formation behavior prognosis. We help making proper selection of drill string with ADP, when we are asked to. This task also requires a long experience in doing such selection.
3. What are the challenges and solutions for drilling wells in Arctic conditions in Russia?
VAM Drilling (Vallourec Group): In environments with temperatures lower than -40° C pipes are subject to embrittlement and subsequent failure. Failure will most likely occur in the upset area due the concentration of stress which occurs there.
Solutions include using low temperature grades like VAM Drilling’s VM 135 DP-LT with high levels of toughness (impact test) even at -60°C which helps prevent brittle failures which occur in low temperature. Our pipes have been certified by VNIIGAZ for use in severe arctic environments.
Tenaris: From a drill pipe perspective, one of the main challenges facing operators developing wells in the Arctic region is dealing with the extremely cold weather. Tenaris has been helping Russian operators to address this and other issues in the Arctic. VNIIGAZ, the research institute of GAZPROM, has certified high toughness drill pipe manufactured by Tenaris.
TMK: From the drill pipe operation perspective, the key complexity is low temperatures. Drill pipe operation in the Arctic region presumes that the drill string should include low-temperature drill pipes at ambient temperatures. Promptly after the drill-pipe stand has been included in the working drill pipe string, substantial workloads will be applied to it. Until all pipes have obtained slurry operating temperature, all their structural items must be highly resistant to brittle crushing. To avoid brittle crushing in drill pipe structures, all materials used in the pipe and tool joint designs, as well as welding seams, must be highly durable and meet the necessary cold endurance required for arctic conditions. TMK has developed, in conjunction with VNIIGAZ, special requirments for drill pipe used in arctic/ below normal temperatures by Gazprom.
Aquatic: Main challenge is cold temperature and lack of communications. Both factors are favorable for application of aluminium drill pipes. They require less transportation costs, being twice lighter, and they do not become brittle like steel at extremely low temperatures. A good example may be the liquid nitrogen containers which are always made of aluminium.
4. Extended Reach and horizontal drilling are becoming more and more common in Russia. What solutions do you have for these complex deviated wells?
VAM Drilling (Vallourec Group): VAM Drilling offers specific solutions for complex deviated wells including:
» Special high grades including VM-140, VM-150 and VM-165 which are used to produce lighter drill pipes required to minimize torque and drag in ultra Extended Reach Wells.
» Premium double shoulder connections including VAM EIS and VAM Express which set a new connection performance standard at cost efficiencies similar to those of API.
» Special hole cleaning solutions including our Hydroclean product line which reduces or eliminates problems associated with cuttings build-up and excess torque and drag in complex or non conventional wells.
» Services specially adapted to your needs in order to guarantee performance:
• Drill string design including specific pipe dimensions and drill string composition
• Running assistance and services
Tenaris: Complex deviated wells such as those being increasingly developed in Russia are extremely demanding for both pipe body and pipe connection. At Tenaris we are able to manufacture High Strength drill pipe using very robust proprietary steel grades (for example NK-S140 or NK-S150), which offer improved delayed fracture resistance. Our Wedge Series 500TM family in particular is recognized for its field-proven robustness.
TMK: An important indicator for drilling such wells is the ability of pipes to resist fatigue breakdowns, together with their high strength. Tool joints must transmit torques considerably greater than in standard structures. For such wells, TMK supplies specially designed TDS and TDSA series drill pipes, as well as high-strength drill pipes with special upset design and an ultra-strong DEXTER tool joint.
Aquatic: The main challenge in drilling horizontal and extended reach wells is serious drag which appears in horizontal sections. This drag depends on weight which pushes drill string to the borehole lower wall. Twice the reduction of weight with application of aluminium drill pipes can proportionally reduce the drag of the drill string. Proper composition of drill string assembly, with ADP on the horizontal section, where they reduce drag, and steel pipes at upper intervals, where most strength is needed, can increase the length of existing extended reach wells by additional 20-30%.
5. What additional safety margins can be gained from using standards beyond API or GOST (NS1, DS1, NORSOK or customised specifications)?
VAM Drilling (Vallourec Group): NS1 and DS1 are specifications originating from the North Sea and Canada respectively while NORSOK originates from Norway. These specifications are designed to increase fatigue resistance, safety margins and reliability of pipes.
Beyond these main specifications, customized specifications can be developed together with pipe manufacturers to meet specific drilling challenges including improving the cleanliness of steel used as well as pipe tolerances.
Tenaris: The reason these well-known specifications are so valuable is because they help oil and gas exploration and production companies to avoid catastrophic structural failures. The concept behind them is “Leak before Break” (or wash-out before twist-off). In order to meet this criterion, drill pipe must be able to demonstrate high toughness properties. Thanks to the outstanding cleanliness of the steel we produce at Tenaris, we can supply drill pipe with unparalleled robustness that not only meets but also exceeds these specifications.
TMK: TMK engineering services work closely with the drilling contractors’ engineering services to assess the most dangerous conditions in the process of drill pipe operation and to implement a number of drilling processes associated with the application of pipes. Where required, additional safety factors for specific drill pipe load conditions are defined jointly with the customer. Using these additional specifications during the manufacturing process, we provide the customer with the advantage of loads that can be added to the drill pipe during operation, by, for example, reducing the tolerances on the thickness of the walls.
Aquatic: Application of customized industry standards can give additional safety margins. Still their implementation will require increase in cost of the drilling process. Each company operating in certain country follows its own documented rules and procedures, based on country’s laws and company’s experience. For most countries ISO standards are applicable, they provide sufficient safety margins, and have duplicates as national standards. ISO standards can be used as basis requirement, additional customized industry standards can be used as an option.
6. What associated services do you offer to optimise drilling performance?
VAM Drilling (Vallourec Group): VAM Drilling offers a wide variety of services to improve your performance:
Before drilling
» Assistance in drill string design
» Customer specification design
» VAM Schools – rig crews and drilling contractor training
During drilling
» 24/7 onshore and offshore onsite running assistance
» Efficient pipe preparation
» Support of VAM Drilling engineers
After drilling
» Performance analysis
» Qualified licensee workshops located near all major oil and gas fields
Tenaris: Ever since we started manufacturing drill pipe in 1953, we have been recognized as a leading provider of value added services. We conduct intensive field failure analysis and have a policy of continuous improvement which we implement in cooperation with our customers. This allows us to offer a number of associated metallurgical services while ensuring consistent quality control from steel making to welding. In addition, we offer field services through a local team of Russian field service specialists that can assist customers wherever in the country their projects happen to be. These services include training, inspection of drill pipe at the rig site, running assistance and threading assistance.
TMK: TMK – a company producing the entire range of national steel drill pipes – has sufficient scientific and industrial potential and a well-developed oil service business infrastructure located in close proximity to key oil and gas regions. The company can organize a complex and a relatively wide scope of services in the area of drill pipes and a number of drill string design components. The goal is to decrease the cost of the drilling process implementation for our customers, providing high quality service and support.
Aquatic: We offer engineering services which include drill string analysis and selection of proper drill string assembly for each certain application, as well as support of our customers in carrying out inspection and problem elimination. We work on constant improvement of our products, our engineering team is ready to make all the necessary modifications to our products, if requested.
7. How do you see drilling in Russia in the future? What are you developing for meeting these challenges?
VAM Drilling (Vallourec Group): As oil fields become increasingly difficult to reach, drilling in Russia, like in the rest of the world, will become more complex. We can therefore expect more of ERD wells, offshore drilling and drilling in Arctic environments.
VAM Drilling is dedicated to providing innovative solutions for its clients. In the coming years, you can expect new high performance products and the support of increasingly knowledgeable and customer oriented individuals. We’re always looking to develop new solutions including:
» New steels for low temperatures, Sour Service, high strength grades for ERD applications;
» Gas tight solutions;
» New hole-cleaning innovations.
Tenaris: Russia has vast untapped oil and gas reserves, and bringing those resources to the surface will involve a series of operational, environmental, economic and logistical challenges. Tackling each of these challenges will call for careful consideration when it comes to the tubular technologies that operators will require to drill new wells. From our mill in Japan, we are developing a strategic drill pipe division to meet growing demand for our products and services from customers in the CIS region. We are also committed to the development of new products that will complement and expand our range of High Strength, High Toughness, and Sour Service drill pipe for highly demanding wells.
TMK: The development of perspective fields in Russia will be connected with the application of advanced drilling technologies that also require innovations in drill pipe specifications. For such purposes, TMK has established the TMK Premium Service innovation company, aimed at satisfying the drill pipe market needs for high-technology and energy-efficient products. Within a short space of time, experts within TMK – Premium Service made significant breakthroughs in the production of drill pipes in Russia. Our current production meets the increasing requirements of drilling companies active in well construction both on and offshore in remote regions of the Far North and Arctic.
Aquatic: Drilling in Russia will become more complex. The percentage of horizontal wells will increase. Aluminium drill pipes will be the right instrument meeting growing challenges. At the same time we are developing new products which will be claimed by the developing market. These include aluminium spiral ribbed drill pipe, aluminium tubing and casing. Offshore drilling will become more demanded. We have some aluminium alloy products for sea application as well, they are risers of different kinds: drilling and production riser.
HARDBANDING
Hardbanding is not as prevalently used in Russia as it is in other regions across the world.
In what situations would you recommend to operators and contractors that HB is applied to strings in Russia?
VAM Drilling (Vallourec Group): In deviated wells, Hard Banding is strongly recommended to reduce the wear that occurs on the tool joint due to casing friction. When in open hole, Russia’s aggressive geology formations make it important to apply hard banding to your tool joints in order to prolong their lifetime.
Tenaris: Applying hardbanding would be particularly beneficial in horizontal and extended-reach wells where tool joints in an open hole can be severely worn out due to the existence of a hard layer in the formation being drilled.
TMK: We suggest applying protective hardbanding to tool joints in the process of drilling inside casing to protect both the casing and the tool joint from damage.
Key casing wear areas:
» first section of the marine riser (flexible connection);
» mouth, preventer;
» upper casing joint below the mouth within the range of 0-1800m;
» wells with a high-level crookedness interval;
» well profile dog-legs;
» S-shaped wells;
» areas emerging under high side loads and strong extension of the drill pipe string;
» areas with bad casing cementation, etc.
As we can see, there are relatively many causes that may lead to casing damage and their elimination will require considerable resources.
On the other hand, the tool joint drum also can also wear down in the open well shaft which, in turn, will cause premature breakdown of the drill pipe string and, therefore, increase drilling costs.
Aquatic: Hardbanding is not as common in Russia as in other places of the world. This accounts to the traditional application of downhole motors along with rotation of the drill string versus rotary drilling, which is more common outside Russia. Still, nowadays hardbanding gains its market in Russia.
In case of rotary drilling in hard formations, is the first thing, which comes to my mind. Other applications may be considered as well. For example, better cuttings transport requires, in some cases, rotation of the drill string up to 180 RPM, pipe without hardbanding will not last long in such conditions. Hardbanding is said to reduce the wear of the casing, is another “pro” for its recommending.
1. Why do you feel HB is not widely utilised in Russia?
Arnco: Drilling in Russia up until the 1990’s was largely dominated by the use of aluminum drill pipe (ADP). Tungsten carbide has always been in use, applied to ADP as an initial application after manufacturing and onto the small percentage of traditional steel pipe in use. Casing-friendly harbanding products emerged in the early 1990’s, which also coincided with a major downturn in drilling activity in Russia. This prevented wide-spread knowledge and interest in the use of new advanced hardbanding materials. Since then, and especially in recent years, this has changed as the benefits of advanced, casing-friendly hardbanding have been realized in Russia.
Postle Industries: Hardbanding is closely linked to oil and gas drilling activity. As drilling activity increases, the need for hardbanding increases. Hardbanding technology has existed for over 60 years, but for many companies in the drilling industry, the benefits are not well known. Instead of hardbanding to extend tool joint life, some companies simply replace drill pipe after the tool joints have lost their useful life. For many years, hardbanding was seen primarily as a maintenance cost, to be avoided if possible. Even for application on new drill pipe to prevent wear, some companies consider hardbanding to be an extra cost that is unnecessary until after being used in the hole. Drilling companies are now seeing that hardbanding can save them thousands of dollars.
NOV: Price and lack of information on the benefits of hardbanding. The industry has probably not done a good job of educating Drilling Engineers, Operators and Drilling Contractors in Russia. It’s been proven many times over the past 30-40 years that hardbanding does extend the life of tooljoints and that bare tooljoints do cause damage to casing.
2. What benefits does HB bring to Russian operators and drilling contractors?
Arnco: Hardbanding, like many other established drilling services and solutions, delivers measurable long term cost efficiencies and a proven return on investment for operators and contractors alike. Operators benefit by preventing casing wear, eliminating casing failures and reducing frictional forces while rotating. Drilling contractors can significantly extend the life of the tool joint with use of highly durable hardbanding products. As a widely accepted measure towards protecting drill string and casing assets, the application of casing-friendly hardband material is required for most drilling programs managed by international oil companies.
One example, that generated scientifically measured results, took place in 2005 when Weatherford supplied Chevron with a drill string for their Captain Drilling Campaign with Arnco 300XT applied. Using an analytical approach, Weatherford estimated that the new quality control measure of applying Arnco 300XT to all tool joints resulted in savings of US$3 Million. (Campaign details – Location: U.K. North Sea, Number of wells: 6, Formation: Highly abrasive, unconsolidated sands, Hole size: 12-1/4in., Angle: 90° max, Casing: 9-5/8 L80, Footage: 27,771 ft, Rotational hours: 461.3)
Postle Industries: Hardbanding provides economic benefits to both Operators and Drilling Contractors, who have opposing strategies of hardbanding. Since Operators own the casing, they do not want to wear a hole in their casing. For the Drilling Contractor, the interest is extending the life of the tool joint. When drilling was mostly vertical, very little attention was given to casing wear. However, as drilling has gone deeper, and multi-directional, the technology of hardbanding has become a significant factor and increasingly important. For Operators, it has been proven that a “bare tool joint” will wear a hole in the casing and hardbanding will not wear a hole in the casing. For the Drilling Contractors, the right hardband will extend the life of the tool joint many times over.
NOV: Operators: If drilling in cased hole is required then hardbanded drillpipe will benefit drilling operations by decreased casing wear and decreased coefficient of friction allowing more efficient drilling.
Drilling Contractors: By maintaining a good hardband program, pipe owners can see a greater return on their investment in drillpipe by extending the life of the tooljoints and reducing the number of joints downgraded for circumferential wear.
3. How would the client select which HB material is best to use for their specific well construction plan? Not from their experience.
Arnco: A highly durable product that also exhibits very low casing wear is good for any well construction plan, cased or open-hole. The combination of metallurgical factors that affect hardbanding performance can be challenging to understand and interpret. As a pioneer in the casing-friendly hardbanding market, Arnco has always invested a significant amount of effort and time into educating customers. There are a number of ways to evaluate the expected performance of a hardbanding product, many of which are included and explained on Arnco Technology’s website. Most importantly, downhole performance, ease of application / reapplication and price should always be considered when selecting a hardbanding alloy.
Postle Industries: The products that are available today are all considered “casing friendly”, so the concerns from the Operators should be satisfied. From the Drilling Contractors perspective, they need to consider how much tool joint protection is required and how abrasive are the drilling conditions. We produce two products, Tuffband and Duraband. Tuffband offers very good abrasion resistance, while Duraband offers the best protection for the tool joint, and both are casing friendly. Another important consideration is the re-application cost. If the previous hardband layer has to be removed before a new one is applied, the cost of the work can increase by 400%. Both Tuffband and Duraband can be re-applied over themselves without removing the previous layer. By choosing the right hardband, and planning for re-applications, considerable money can be saved.
NOV: In some areas Operators have computer software that can pinpoint problem areas for casing wear. By studying these well profiles, engineers can determine the severity of anticipated casing wear and therefore make an informed decision of which hardband would better serve each well profile.
PIPE DOPE
Would you recommend that pipe dope be applied to all your products?
VAM Drilling (Vallourec Group): All VAM Drilling pipe is supplied with connection protection dope and it is important to apply additional running dope on the rig floor in order to avoid thread damage while making-up the connection. Applied properly, dope can guarantee correct make-up torque values subject to the proper definition of friction factors.
Tenaris: Yes. We stipulate the application of dope as mandatory in all drill pipes because, among other reasons, it helps to protect connections from rust. For casing and tubing we offer our Dopeless® technology, a dry multi-functional coating that is applied to the connection by the pipe manufacturer in the controlled, industrial environment of the mill ensuring consistent quality and operational reliability.
Aquatic: Yes, pipe dope shall always be applied. We use mainly tool joints which completely meet requirements of ISO 11961: the same threads and materials. The recommended dopes are the same as with other steel pipes. For aluminium connections, as in aluminium integral joint pipes and tubing, the dope shall be special.
1. What are the most important functions of pipe dope?
Bestolife: Lubricate – Seal – Protect
» Provide sufficient lubricity to overcome initial friction between threads during initial stages of make-up.
» Prevent metal-to-metal contact and galling.
» Provide a leak proof seal between shoulders for drilling fluids.
» Control / prevent downhole make-up during drilling to avoid excessive stresses in the connection.
» Enable connection to be broken-out with less torque than at make-up.
» Leave no residue or plating on shoulders at breakout.
» Prevent corrosion of threads/shoulders during drilling operations, storage and transit.
Jet-Lube: They must effectively lubricate the drill pipe’s thread form during make up and break out, whilst keeping any adverse environmental impact to a minimum. This last point was the driver behind Jet-Lube’s decision, taken many years ago, to remove lead and zinc from our metallic compounds whenever possible. It was also this goal that led to the design and development of Jet-Lube’s “ECF” range of products, one of which being in conjunction with the major Norwegian operator, and all of which carry the highest possible HOCNF classification for a finished compound of “E” for the UK and Netherlands, and “Yellow” for Norway.
As a point of interest, it was the advent of these bio-degradable, non bio-accumulating “E” and “Yellow” classified thread compounds that led some of the thread manufactures to seriously re-evaluate the arguments in favour of continuing with “dopeless” technology research, as one of the reasons for this high cost product, environmental protection, had disappeared when Jet-Lube’s ECF range of thread compounds came to the market place.
I must confess to disliking the term “dope”. Pipe dope to me refers to the old technology products which consisted of little more than a base grease containing heavy metal particles, the presence of which was designed to assist in the makeup, and break out of drill pipe connections. Today’s products are more accurately referred to as thread compounds, such are the advances that have been made in recent years to the chemistry involved in the manufacturing process. Today’s compounds are highly engineered products, designed to meet the performance demanded by today’s more severe drilling requirements. (High or low temperatures, heavier string weights, faster rotary speeds, high mud pH and strong emulsifiers, high angles, etc.)
2. What key recommendations would you give on for doping application?
Bestolife:
» Stir product thoroughly to re-blend any oil separation or settlement of component solids that may have occurred during shipment and storage. This is particularly critical for high density materials such as those containing lead and/or zinc.
» Ensure threads and shoulders of both pin and box are clean and free of drilling fluids or other contaminant residues prior to the application of the compound.
» Apply an even coating of thread compound to the threads and shoulder(s) of both pin and box. It is important to apply to both internal and external shoulders of box end connection on double shouldered (DSTJ) connections.
» Replace lid on container after use to prevent contamination.
KEY ISSUE: Application (or lack of) of the pipe dope when making up / running connections. Unless there is a good coating of compound uniformly covering the entire contact surface area of the pin and box, and especially, the shoulders, there is the risk that it may be unable function correctly and prevent metal to metal contact or create a leak proof seal between the shoulder faces – a process that absorbs part of the make-up torque energy during compacting / flattening / squeezing of the solid particles into a seal. In which case this additional (surplus) energy
will be transferred into the connection and it will over tighten – and be difficult, if not impossible to break-out.
Jet-Lube: Upon opening the pail, in the case of a metallic compound, the product should be stirred with either a brush or other suitable device to re-blend any oil separation, or settling of the component solids that may have occurred during shipment and storage.
With a non-metallic, stirring should also take place especially if using a compound of a thixotrophic nature (stiffens upon sitting but softens with mixing) such as a Jet-Lube ECF product. Care should be also be taken that at no time contamination of the compound in the container occurs, i.e. dirt and other debris.
Under no circumstances should any material such as diesel fuel, kerosene, motor oil, etc. be added to the compound to improve ease of application. Thinning may make it easier to apply but contamination or adulteration can change the friction factor of the compound, and also degrade the galling resistance properties. Unfortunately this practice is not uncommon in Russia, and other parts of the world especially when temperatures are low. Used motor oil is often the “thinning agent” of choice Russian sources report.
The thread compound should be applied liberally and uniformly to the entire contact surface of both the pin and box. The practice of slapping a “gob” of compound on one side of the pin or box and depending on the pipe rotation during make-up to distribute the compound over the connection surface, as was common with the high percentage lead or zinc compounds, is not sufficient for most of the nonmetallic thread compounds.
If the pins are doped while tripping or when the pipe is on a rack, care should be taken to ensure that when the string is stood up on the rig floor prior to running, that the compound does not pick up contaminants (e.g. dried mud, etc.) off the rig floor. Certain drilling mud additives can make adhesion difficult. In these cases the joints can be sprayed/washed after tripping then apply the compound to the pins before racking the pipe, as opposed to trying to reapply compound dope the box while such mud is still present.
3. Are there specific GOST standards or operator requirements for dope when operating in different regions in Russia, i.e. arctic, onshore etc? What are your solutions for these regions?
Bestolife: Legalization, regulations and standards covering the supply and use of thread compounds and other chemicals for oil and gas exploration in Russia follow a similar pattern to those we encounter elsewhere in the world. They cover occupational health, safety and impact on environment. Major operators such as Gasprom JSC and Sakhalin Energy have their own technical qualification requirements, as do drill pipe manufactures such as TMK, Tenaris and VAM Drilling.
We are well qualified to meet these requirements using the knowledge and experience gleaned from nearly 80 years dedicated to producing the finest quality products for every situation. Beginning with founder I. H. Grancell’s ‘Bestolife 270, the first thread compound to combat galling, seizing and downhole makeup, through to current generation eco-sensitive Bestolife “4010”NM we have researched and formulated compounds for unique environments, offering a diverse line-up of superior products. Bestolife’s motto has remained constant since the 1930s: No matter the condition, Bestolife has the solution, whether it is onshore in Western Siberia, offshore in the arctic cold of the Barents and Pechora Seas or the environmentally sensitive Sakhalin Island.
Jet-Lube: There are currently over three thousand active GOST R standards but to date Jet-Lube is not aware of any of these standards pertaining specifically to thread compounds, nor have any of our end users referred to such a standard requirement for these types of product. The drilling companies operating throughout Russia that use our compounds do so having initially conducted their own in house product testing and qualification procedures.
Other participants of this discussion might have more information, but as far as I know whilst there is word that this situation might change in the future, at present, even if this is the case, it is in draft form only at best.
With regard to how Jet-Lube provides solutions to the issues that arise from operating in this part of the world, as you might expect, with their ability to be applied at temperatures as low as minus 65 degrees Fahrenheit, Jet-Lube’s arctic grade thread compounds are some of our most popular drilling products sales wise.
4. How widely used are environmentally acceptable dope compounds in Russia? What are the advantages / disadvantages compared with standard copper, lead and zinc based products?
Bestolife: Use of eco-friendly compounds is growing. Demand likely to increase with offshore development projects such as the Shtokmanovskoye gas and Prirazlomnoye oil fields.
In 1992 we introduced Bestolife“3000”®, the first totally non-metal drilling compound to provide performance properties similar to heavy metal-based compounds. Bestolife 3010 Ultra followed in 1999; a product that has since become the most widely used eco-friendly pipe dope for offshore use worldwide, and the compound of choice for many international offshore drilling contractors and operators, irrespective of location, including Sakhalin Energy. In 2004 further development lead to the introduction of Bestolife “3010”®NM SPECIAL, the very first eco-friendly compound to be registered as Yellow in Norway to enable Statoil to commence drilling Snøhvit development wells in Barents Sea in January 2005.
Today with the introduction of Bestolife “4010”NM, a genuine multi-purpose compound suitable for both drill pipe and premium metal-to-metal seal casing/tubing connections in super high chrome steels, there is little or no difference in downhole performance compared to standard heavy metal compounds. The main difference tends to be price with eco-friendly products appearing more expensive, however their much lower density and physical properties make them easier to apply in a thin even coating, thereby reducing consumption, minimising waste and release to the environment.
Jet-Lube: The adoption of non-metallic compounds, including our biodegradable, non bio-accumulating, environmentally friendly drilling compound NCS-30 ECF, has been slow to date sales volume wise when compared to others within our drilling compound range. In that regard this market does lag behind the rest of the industry worldwide somewhat.
For instance NCS-30 ECF is widely used in the UK section of the North Sea, indeed three of the majors specify its use, while its use is wide spread in the Norwegian sector also.
That said, some of the more progressive Russian end users are either currently looking to change, or have changed, to our non-metallic offerings, so progress is being made from the environmental stand point.
The advantages when considering these non-metallic, biodegradable compounds over the copper based products for instance, stem more from a usage point of view.
Performance wise, there is little difference between the two, but as the Jet-Lube ECF products weigh less per gallon than any metallic compound, there is more volume of ECF product for any given fill weight of the pail than is present within a pail of heavy metal compound.
This means the customer gets more compound for his money, and therefore, when applied correctly, more pins and boxes treated per pail of ECF than with a copper
based product.
With lead and zinc based compounds being heavier still, the amount variance is even greater.
INTERNAL PIPE COATINGS
What is the level of demand for Internal Plastic Coatings (IPC) in Russia at the moment?
VAM Drilling (Vallourec Group): There is an increasing demand in Russia for IPC from major vertically integrated Oil & Gas Companies and we expect it to be a standard for all companies in the coming years due to aggressive environments. Thanks to IPC drill pipes are better protected against pitting corrosion and therefore eventual washouts. As a DP manufacturer we rather recommend application of IPC on all drill pipes.
Tenaris: We haven’t had any special requests for IPC from Russian customers yet. However, we’d like to stress that we always recommend the application of IPC to avoid localized pitting occurring on the internal surface of tubular products.
TMK: 2,500,000-3,000,000 TPA.
Aquatic: I suppose that the level of demand is around 5%.
1. Coatings Supplier: How does IPC minimise the risk of drill string corrosion for contractors while drilling?
NOV: Since most drilling mud’s are water-based, they are capable of causing extensive corrosion pitting due to entrained salts and from CO2 and H2S picked up from the formation. Aggravating this problem is the oxygen that is picked up as the mud circulates through the shaker and mud pit, which increases the mud’s corrosive nature. Corrosion can exacerbate the stresses that severe drilling operations inflict upon your drill pipe, leading to the rapid development of fatigue cracks and ultimately catastrophic downhole pipe failure. Approximately 85% of fatigue failures occur near the pipe’s upset area where the reduction in bodywall from the tool joint to the pipe body localizes the stresses adjacent to the upset region – causing a costly failure to occur relatively early in the life of your drill pipe. NOV Tuboscope’s internal plastic drill pipe coatings offer protection through the entire pipe internals. Preventing undue corrosion on the internal of the pipe is the first step in minimizing the stress isolations that can lead to pipe failure. Reduction in loss of the wall thickness also further extends the life of that drill pipe asset. The internal coatings utilized for drill string protection are thermoset materials. What this means is that during the coating application, the applied material is cured with temperature (typically between 220°C and 245°C). This will leave you with a highly crosslinked polymeric material capable of being a barrier to the drilling environment. During drilling operations, the coating can be exposed to a variety of corrosive species, so the coating type and application parameters must be sufficient for proper protection. So providing this physical barrier will stop the corrosive fluids from reaching the steel substrate therefore stopping the corrosion reaction from taking place.
DJ Coatings: The application of internal coating presents a barrier between the corrosive fluids used during the drilling operation and the internal surface of the drill pipe.
2. Aside from corrosion what other problems can IPC solve and what benefits does this bring?
NOV: There are two additional benefits that can be seen with the use of internal plastic coating: improved hydraulic performance and the mitigation of scale adhesion to the pipe surface. The internal coating, by nature, has a very smooth surface finish. The bare pipe surface will be ten times rougher than the internal coatings surface. What this will lead to is reduced friction generated at the surface from the fluid flow and this reduced friction leads to increased flow through a coated string of pipe. Flow rate increases of greater than 10% have been realized through coated drill strings versus bare strings. This improved hydraulic flow can lead to more fluid to the bit, better solids lift and removal, or even reduced utilities needed for the mud pumps. Additionally, the coating surface also provides for the mitigation of scale adhesion. On the surface, this does not immediately seem like a huge deal, but when you consider the detrimental issues that can be caused by scale and dislodged scale, you begin to see it true importance. Scale can clog up nozzles on the drill bit, clog up mud motors, minimize mud lift efficiency, and minimize hydraulic flow. When looked at in completion strings, scale can interfere with packer setting and can also dislodge and negatively impact the skin value of the prepared reservoir portion of the wellbore.
DJ Coatings: While the main advantage of ipc is to prevent corrosion there is also some gain in the hydraulic efficiency of the smooth coated surface vs the rough surface of bare steel. In drill pipe the ipc reduces internal corrosion and scale formation that can ultimately flake and cause plugging of the fluid jets at the bit which will require that the pipe be withdrawn from the well so that the bit can be cleaned.
For use in production wells the ipc can extend the life of the pipe many times that of bare pipe. In corrosive wells the steel pipe will be attacked agressively leading to penetration thru the wall and a failure which would involve arranging for a workover rig to remove the damaged pipe and replace with new material. The cost for this can be extensive and frequent. With ipc the period between workovers can be greatly extended saving money and downtime.
In wells that produce oil heavy with parrafin the smooth surface of the ipc can reduce adherence of the waxy material to the pipe internal surface which will ultimately plug the bore and stop production. Ipc can greatly extend periods before mechancial or hydraulic cleaning is required.
3. How can an operator decide which material is best to use for their specific well environment?
NOV: With several different coating materials available in drill pipe applications, understanding when to use one over the other can lead to even greater coating performance. Within our product line, we do not differentiate between our drill pipe coatings based on temperature or pressure capabilities. Where you will see the products differentiate themselves is in the realm of H2S resistance, chemical resistance and abrasion resistance. Knowing the expected well environment (concentration of corrosive species), expected chemical program (temperature of exposure and the concentration and type of chemical), and the type and frequency of pipe intervention (fracing, cementing, gravel packing, wireline runs, coiled tubing runs, etc) will allow you to choose the coating that will provide the most benefit for the given application. We do not expect the operator to decide on their own which coating will best suit their needs. NOV Tuboscope will be integral in the decision on which coating will best suit their environment.
DJ Coatings: For production wells the most suitable ipc is determined by the fluid/gas composition flowing thru the pipe along with the temperatures that can be anticipated.
