Vol. 4, Issue 4 Product Performance: 12-1/4" Success in Sisi Nubi Field Challenge In the Sisi Nubi Field in Indonesia, drill through 0.5-2.0 m stringers of moderately hard to hard limestone effectively. In previous similar applications, rate of penetration (ROP) suffered with multiple PDC designs, due to the clay drilling also required in the application. Solution The Varel team worked directly alongside the operator, at their request, to develop a solution and to enhance drilling procedures. Preliminary electronic log data pointed to "easy" drilling for PDC bits. When Varel's Drilling Impedance Model (DRIMP) was employed, which plots weight on bit versus ROP, a section at 1100 m to 2100 m was pinpointed as causing extreme drilling difficulty when drilling with a PDC. Knowing this, designers suggested: • An aggressive bit with more effective cutter standoff • Increased junk slot volume • Modified hydraulics A 12-1/4" Navigator™ VRT513OPBTDGH PDC bit with an aggressive cutting structure was selected to drill through stringers quickly without inducing undue drilling vibrations. Designers chose 13mm oval cutters, for point loading benefits, to be backed up by round cutters. Backrake angle was also enhanced in order to lead to efficient cutting action through the stringers. The modifications in the junk slot area and the hydraulics were made to eliminate bit balling and microballing by improving bit face hydraulics. Blade shape and curvature were studied and modified for better cleaning. An increase in nozzles for the design was meant to assist hydraulically without resulting in washout in clay sections. The design was also optimized for steerability and the drive system being utilized. Results The bit succeeded to drill the entire 12-1/4" section in one run at an on-bottom average ROP of 29.8 m/hr with WOB mostly less than ten tons. In addition, the bit successfully built angle from 18 degrees to 48 degrees within 430 m measured depth interval and then held tangent along 245 degrees to section TD at 1801 m true vertical depth. Results showed that as less WOB was applied, an increased ROP and higher torque indicated a higher efficiency of the new cutting structure. The ROP was somewhat controlled within 25 and 50 m/hr throughout the entire run. This was a good practice in interbedded formation drilling. While the ROP began to drop after 800m TVD on a previous well, in this instance this bit continued to maintain ROP above 25 m/hr over the intervals covered by three PDC bits on the previous application. A poor drilling impedance indicator was not experienced with this new design. The reduction in ROP across clay intervals still occurred but to a much lesser degree. Instead of dropping ROP from 30 m/hr to as low as 1 to 2 m/hr at times, the low ROPs in clay drilled by this bit were generally between 20 and 30 m/hr . Therefore, it proved that an aggressive cutting structure with good hydraulic design that drills well in clay would help to reduce any potential balling or microballing risk as well as string stacking events in sticky hole. For an extended version of this product performance, please contact Bruno Cuillier with Varel International. Varel Introduces DuraTech™ Roller Cone Bits Varel has introduced the next generation of steel-tooth roller cone bits – the Varel DuraTech™ Series. This series delivers ultimate rates of penetration (ROP) with reformulated hardmetal protection that provides life-enhancing durability in the most demanding environments. The steel-tooth bits, available from 3-3/4" to 13-3/4", are built to withstand the added stress operators apply to bits when additional weight and greater RPMs are necessary. The series is designed to provide: • Added durability in abrasive environments • Increased ROP • Directional responsiveness • A solution for sticky shale drilling Varel used a systematic approach when developing the DuraTech series, delivering a product that can reliably withstand high-energy inputs while maintaining expectations of high ROP and increased footage. DuraTech bits combine innovative manufacturing processes, quality materials and highly trained personnel, and have repeatedly been proven in field tests to provide reliable, lasting performance. For more information, please visit Varel DuraTech Series or contact your Varel representative. Tradeshow Recap AIMEX The Australian contingent of Varel International recently exhibited at the AIMEX Mining show in Sydney during September. The exhibition, held every four years, is considered to be the premier trade showcase of mining product development. It is the largest mining exhibition in the Southern Hemisphere, and this year was attended by more than 30,000 visitors from overseas and all states throughout Australia. The Varel booth was well attended by clients from Australia and South East Asia with new leads being secured for a number of mining projects. Supporting the show were representatives from Varel Australia, and Varel's Australian and Indonesian distributors. DUG SA With ten drill bits specific to shale drilling applications, the Varel team that exhibited at the recent Developing Unconventional Gas (DUG) Eagle Ford exhibition in San Antonio was well prepared for inquiries. This gathering is said to be the the largest gathering of unconventional gas professionals in the region and boasted more than 4,000 attendees. Varel was also in good company and was joined by more than 300 additional exhibitors. The Varel team enjoyed meeting new customers and looks forward to assisting customers in their unconventional resource plays. MEOS Varel recently participated in the 17th Annual Middle Eastern Oil Show (MEOS) in Bahrain. MEOS is the most established exhibition of oil and gas products and services in the Middle East, attracting NOCs, IOCs and major operating companies. The conference, organized by the Society of Petroleum Engineers (SPE), is the largest and best attended technical event of its kind in the region. This year marked the largest edition of MEOS in the 32 year history of the series, having registered a record total of 7,199 conference delegates and visitors. Downhole Products (DHP) Named in Northern Star Business Awards DHP was recently recognized as a finalist for the 2011 Aberdeen and Grampian Chamber of Commerce's Northern Star Business Award. The award recognizes a company's economic contribution to Scotland and the UK as a whole. According to the organizers, the Awards bring together the brightest and best in the region recognizing the hard work of both individuals and companies who are leading the way within their own companies or sectors. DHP was selected as a finalist based on their growth, despite the recession, during the previous years. The company grew their human capital by 50 percent, increased its revenue by 50 percent and expanded its global footprint through operations in the United States, Kuala Lumpur and Dubai. Congratulations to the entire team at DHP! Upcoming Shows DUG East November 15-17, 2012 Pittsburg, PA Booth# 808 SPE/IADC Drilling Conference March 6-8, 2012 San Diego, CA Booth#402 SPE/ICoTA Coiled Tubing Conference March 27-28, 2012 The Woodlands, TX Kentucky Blasting Conference Lexington, KY December 1-2, 2012 Booth #16 ISEE Explosive & Blasting Techniques Nashville, TN February 12-15, 2012 Booth#215