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New Increased Torque Tool Joint Connection Offers an Alternative to Customers with New Technology to Advance Connection Performance.This paper was prepared for presentation and review to interested customers of PTECH Drilling Tubulars, LLC. Prepared by: Nels Wickander ABSTRACT As new discoveries of oil reserves are found the petroleum industry has moved toward more rigorous difficult drilling applications such as ultra deep water, extended reach, high-angle, and short-radius to obtain its product. With this in mind new technology is required for development of drill string connection designs to safely and efficiently meet the objectives of these new projects. This case study describes new rotary shoulder connections that provide maximum operational and economic advantages for those rigorous drilling applications. INTRODUCTION PTECH Drilling Tubulars, LLC. has developed a new increased torque double shoulder connection that is optimized for its prospective drill pipe size. This development stems from the need of the petroleum industry to have an alternative, more economical, high performance drill pipe connection, to what is currently in the market. This new design is a first-generation, dual-shoulder connection that has been designed with optimal connection performance in torque, tension, and fatigue resistance. The increased critical cross-sectional areas and shoulder contact areas create a unique design that increases the mechanical properties of the connection. The design also takes advantage of the 135ksi specified material yield strength (SMYS) to further increase the performance of the connection design. The connection’s increased torsional capabilities allows for the use of an enhanced streamline geometric tool joint design. The connections can be configured with a smaller OD and larger ID as compared to standard API connection while maintaining torsional capacity. Another development to discuss is the new thread form that provides increased toughness, reduced connection stiffness and improved fatigue life as compared to standard API connections. All designs were analyzed using the latest technology in Finite Element Analysis (FEA), straying away from the typical 2D FEA and migrating to a 3D FEA method. This allows determination, and evaluation of stress distribution on a global representation versus a planar representation. This case study discusses the engineering technology behind the new designs, details results of physical testing, along with applications of were the connection has been used. DESIGN CAPABILITIES AND PROFILE Performance Technology Plus (PTECH+™) is a double-shoulder connection, with a proprietary thread form design, that was designed to take advantage of new technology in material strengths, geometric designs, and design analysis to improve the connection performance. The PTECH+™ connection has the same make-up characteristics of existing double shoulder connections. The connection makes-up liberally from the stab-in to hand-tight position. In the hand-tight position the primary external shoulder makes contact without any axial stresses on the shoulder. As the connection continues to make-up from the hand-tight to power-tight position the box counterbore compresses, the pin base stretches elastically and the secondary shoulder engages. The secondary internal torque shoulder allows for enhanced load distribution across the threaded region and provides increased torsional capacity compared to a standard API rotary shoulder connection. Though the primary external shoulder does maintain significant amount of contact to become a pressure seal, it should not be mistaken for such, since the secondary internal shoulder only functions as a torque stop, not a seal, a small amount of damage is acceptable without affecting the

Page 2 of 3 performance of the connection. The combination of thread tapers and thread forms allows the PTECH+™ connection to have an increase in area at the secondary shoulder; this yields an increase in torsional capacity. PTECH+ provides enhancement in working torques of approximately 65% to 80% compared to a standard API connection of the same dimensions. Though, the PTECH+™ has shallow thread tapers the connection will make-up as fast as a standard API connection, approximately 5% to 15% of the turns to make-up. Even with a slow taper the PTECH+ does not require a stabbing guide; nevertheless, personnel have used them to help prevent any damage to the box primary shoulder. BENEFITS OF THE CONNECTION The design of the PTECH+™ connection provides added benefits to a drilling project. Some benefits are as follow. INCREASED TORSIONAL STRENGTH The PTECH+™ connection provides a significant amount of torque as compared to a standard API connection, this advantage offers higher torques that are required in many critical drilling applications. ENHANCED STREAMLINE GEOMETRIC DESIGN The increased torque capacity provided by the PTECH+™ allows the connection to have smaller ODs and larger IDs while still maintaining increased torque capacity, thus providing a streamline geometric design for each connection. The streamline profile offers the advantage to use selected drill pipe configurations can reduce pressure loss and increase hole cleaning capabilities. This enhanced streamline profile with the added advantage of an enhanced thread form provides a reduction in tool joint and connection stiffness from approximately 13% to 39% on smaller connections and 25% to 39% on larger connections as compared to standard API connections. FATIGUE RESISTANT THREAD FORM An enhanced thread form was designed for the PTECH+™ connection that would allow for a large single root radius; this root radius considerably reduces peak stress in the connection and the connection stiffness. The design permits the connection to withstand larger bending stresses at the connection’s critical cross-section, consequently tolerating a smaller bend radius and larger dogleg severity. EXTENDED FATIGUE LIFE With the advantages of the reduction in connection stiffness and reduced peak stresses in the connection. The PTECH+™ has extended its fatigue life by approximately 193% as compared to standard API connections. These data was gathered through testing of the PTECH+™39 (4-7/8” OD X 2-11/16” ID) connection which showed an improvement in fatigue life of 1,076,947 cycles as compared to the NC40 (5” OD X 2-9/16” ID) which accumulated only 556,631 cycles until failure. INCREASED WEAR TOLERANCE With the increased torsional capacity of the connection, the PTECH+™ extends the service life of the tool joint by tolerating additional OD wear keeping the connection well in range of the pipe torsional capacity before it is downgraded to premium class drill pipe. Additionally, depending on the size the connection can have a total material loss of 3” to 3-15/16” and maximum loss of ¾” on a thread rechase. TORSION TESTING Torsion testing has been performed on the PTECH+™ connection sizes PTECH39+ (4-7/8” X 2-11/16”) and the PTECH55+ (6-5/8” OD X 4-1/4” ID). The connections torsional capacity was first determined by calculation, using a version of the A.P. Farr screwjack formula which has been modified to account for the work performed by the added pin nose area. The connections were then physically tested and the data was correlated to the 3-D FEA results, which matched up accordingly. This method confirmed the stresses in the connection due to make-up torques and ultimate torques, thus permitting to evaluate the design across the product size ranges. The PTECH+™39 was tested in both minimum and maximum internal shoulder gap tolerances provided test results of 42,158 ft-lbs and 41,521 ft-lbs, respectively. The PTECH+™55 was tested in both minimum and maximum internal shoulder gap tolerances provided test results of 90,961 ft-lbs and 88,018 ft-lbs, respectively. At present, a continued testing program is still in place to physically confirm the capabilities of each size

PTECH+™ FIELD HISTORY At present approximately 20,000 feet of drill pipe has been manufactured. A string of 4” 14.00 lb/ft S-135 PTECH+™39 (4-7/8” X 2-11/16”) has been ran in the Bakken Field n North Dakota. The pipe is owned by Brigham Oil & Gas and has been running on Nabors rig 267 and 49, on wells Anderson 28-33 #1H and Brad Olsen 9-16 #1H, respectively. The pipe has been in use at present on 5 wells and was first put in the ground in June 2009. On the first well Anderson 28-33 the well was drilled to a measured depth of 19,989 feet with a total vertical depth of 10,090 feet in June 2009. The well began to kick off at approximately 9,500 feet, a maximum dogleg severity of 7.07 º/100’ was seen at about 10,550’ MD. The average rate of penetration was about 47 ft/hr with a mud pressure of 250 psi. This well was drilled using invert based mud system for the vertical hole and the curve. The curve was drilled targeting the Middle Bakken porosity. On the second well Brad Olsen 9-16 #1H the well was drilled to a measured depth of 20,124 feet with a total vertical depth of 10,622 feet in August 2009. The well was kicked of at approximately 10,180 feet. The maximum dogleg severity of 14.86 º/100’ was seen at about 10,550’. The average rate of penetration was about 110 ft/hour. Oil based mud was used during the vertical and curve section of the well, and salt water was used during the lateral section. A bead recovery system was used along with lateral lube to keep the hole in good condition in the lateral. The well used bit sizes ranging from 13-1/2” down to 8-3/4”, ranging from MX-1 to HCM406Z type bits. The curve was again drilled targeting the Middle Bakken porosity which had a composition of Siltstone, Limestone, Salt, Anhydrite, and Dolomite. CONCLUSION PTECH Drilling Tubulars, LLC. is dedicated to the continuation of developing new and advanced technology. The approach taken is based on customer feed back and customer needs. The advances in the technical products are critical to meet the challenges that our industry has at hand presently and in the future.