Integrated Tubulars Supply Model Provides Cost Savings to Drilling Projects

Classical Oil Country Tubular Goods (OCTG) procurement approach has been practiced in the indus-try with the typical process of setting a quantity level of tubulars ahead of the drilling project, includ-ing contingencies, and delivery to a storage location close to the drilling site. The total cost of owner-ship for a drilling campaign can be reduced in the range of 10-30% related to tubulars across the en-tire supply chain. In recent decades, the strategy of OCTG supply has seen an improvement resulting in significant cost savings by employing the integrated tubular supply chain management. Such method integrates the demand and supply planning of OCTG of several wells in a drilling project and synergize the infor-mation between the pipes manufacturer and drilling operators to optimize the deliveries, minimizing inventory levels and safety stocks. While the capital cost of carrying the inventory of OCTG can be reduced by avoiding the procurement of substantial volume upfront for the entire project, several hidden costs by carrying this inventory can also be minimized. These include storage costs, maintenance costs, and costs associated to stock obsolescence. Digital technologies also simplify the tasks related to the traceability of the tubulars since the release of the pipes from the manufacturing facility to the rig floor. Health, Safety, and Environmental (HSE) risks associated to pipe movements on the rig can be minimized. Pipe-by-pipe traceability provides pipes’ history and their properties on demand. Digitalization of the process has proven to simplify back end administrative tasks. The paper reviews the OCTG supply methods and lays out tangible improvement factors by employ-ing an alternative scheme as discussed in the paper. It also provides an insight on potential cost savings based on the observed and calculated experiences from several operations in the Asia Pacific region.

Bottom Hole Assembly Design Enhancement Successfully Eliminate Hole Problems and Reduce Significant Drilling Time : South S Field Case Study

For S-15 and S-14 wells at South S Field, drilling of the 12-1/4” hole section became the longest tangent hole section interval of both wells. There were several challenges identified where hole problems can occur. The hole problems often occur in the unconsolidated sand layers and porous limestone formation sections of the hole during tripping in/out operations. Most of the hole problems are closely related to the design of the Bottom Hole Assembly (BHA). In many instances, hole problems resulted in significant additional drilling time. As an effort to resolve this issue, a new BHA setup was then designed to enhance the BHA drilling performance and eventually eliminate hole problems while drilling. The basic idea of the enhanced BHA is to provide more annulus clearance and limber BHA. The purpose is to reduce the Equivalent Circulating Density (ECD,) less contact area with formation, and reduce packoff risk while drilling through an unconsolidated section of the rocks. Engineering simulations were conducted to ensure that the enhanced BHA were able to deliver a good drilling performance. As a results, improved drilling performance can be seen on S-14 well which applied the enhanced BHA design. The enhanced BHA was able to drill the 12-1/4” tangent hole section to total depth (TD) with certain drilling parameter. Hole problems were no longer an issue during tripping out/in operation. This improvement led to significant rig time and cost savings of intermediate hole section drilling compared to S-15 well. The new enhanced BHA design has become one of the company’s benchmarks for drilling directional wells in South S Field.

Sand Free Production Success Through Proven Technology Enabler from An Untapped Heterogeneous Reservoir Zone Utilizing Gravel Pack Replacement Methodology

The Belida field is an offshore field located in Block B of Indonesia’s South Natuna Sea. This field was discovered in 1989. Both oil and gas bearing reservoirs are present in the Belida field in the Miocene Arang, Udang and Intra Barat Formations. Within the middle Arang Formation, there are three gas pay zones informally referred to as Beta, Gamma and Delta. These sand zones are thin pay zones which need to be carefully planned and economically exploited. Due to the nature of the reservoir, sand production is a challenge and requires downhole sand control. A key challenge for sand control equipment in this application is erosion resistance without inhibiting productivity as high gas rates and associated high flow velocity is expected from the zones, which is known to have caused sand control failure. To help achieve a cost-effective and easily planned deployment solution to produce hydrocarbons, a rigless deployment is the preferred method to deploy downhole sand control. PSD analysis from the reservoir zone suggested from ‘Industry Rules of Thumb’ a conventional gravel pack deployment as a means of downhole sand control. However, based on review of newer globally proven sand control technologies since adoption of these ‘Industry Rules of Thumb’, a cost-effective solution could be considered and implemented utilizing Ceramic Sand Screen technology. This paper will discuss the successful application at Block B, Natuna Sea using Ceramic Sand Screens as a rigless intervention solution addressing the erosion / hot spotting challenges in these high rate production zones. The erosion resistance of the Ceramic Sand Screen design allows a deployment methodology directly adjacent to the perforated interval to resist against premature loss of sand control. The robust ceramic screen design gave the flexibility required to develop a cost-effective lower completion deployment methodology both from a challenging make up in the well due to a restrictive lubricator length to the tractor conveyancing in the well to land out at the desired set depth covering the producing zone. The paper will overview the success of multi-service and product supply co-operation adopting technology enablers to challenge ‘Industry Rules of Thumb’ replaced by rigless reasoning as a standard well intervention downhole sand control solution where Medco E&P Natuna Ltd. (Medco E&P) faces sand control challenges in their high deviation, sidetracked well stock. The paper draws final attention to the hydrocarbon performance gain resulting due to the ability for choke free production to allow drawing down the well at higher rates than initially expected from this zone.

ESP Optimization Goes Further: Operating Frequency Beyond 60 Hz

Optimization in brown field developments is always challenging in terms of cost. One of it is XY Field, Rimau Block, South Sumatera with more than 70% of artificial lift is Electrical Submersible Pump (ESP). At ESP wells that are already running at maximum operating frequency of 60 Hz, some are still having problems to optimize their potential. The option to replace the pump with a higher rate is less of an option due to high cost. This leaves an opportunity to gain oil production by increasing frequency above 60 Hz. Upon discussion with the ESP Principal on the risks and possibilities, a trial was then planned for 3-wells. Candidates are selected from the list of ESP wells with the following criteria such as already operated at 60 Hz, still have sufficient fluid submergence, and based on simulated motor load at 70 Hz is still at safe motor load level. Frequency was increased gradually while continuously monitoring ESP Parameters (motor load, voltage and harmonic). It is also necessary to monitor the cable temperature as it is directly affected by the frequency changes. For each frequency increment, a well test is also performed to monitor the production changes. The trial was done on 3-wells (XY-364, XY-370 and XY-378), with the following promising results. XY-364 and XY-378 successfully reached the targeted 70Hz, while XY-370 stopped at 65Hz due to a cable temperature issue. Oil gain from this optimization was 48 BOPD with 1,043 BLPD and similar BS&W profile. ESP operation still normal until present day with all parameters at acceptable range. There were, however, challenges found during the trial. Cable temperature of XY-364 increased at junction box and found cable scun loosen. The problem was solved by replacing the cables. For XY-370, found temperature increment at moulded case circuit breaker during trial at 65 Hz. It was decided to hold at existing frequency. Unbalanced motor load at XY-364 and broken capacitor at XY-370 occurred at Harmonic Filter. The problem was solved by replacing the capacitor. The trial proves that we can operate ESP higher than base frequency (60 Hz) and resulted in decent oil gain. This opens an opportunity in ESP optimization above 60 Hz at an even larger scale.

Unlocking Oil Resources without Artificial Lift Using Testing Barge in Tambora Gas Field

Tambora field is a mature gas field located in a swamp area of Mahakam delta without artificial lift. The main objective of this project is to unlock existing oil resources. Most oil wells could not flow because there is no artificial lift, moreover the network pressure is still at Medium Pressure (20 Barg). Given the significant stakes, the option to operate the testing barge continuously as lifting tool is reviewed. The idea is to set the separator pressure to 1-3 Barg, so that the wellhead flowing pressure could be reduced to more than 15 Barg which will create higher drawdown in front of the reservoir. The oil flows from the reservoir into the gauge tank, where it is then returned to the production line by transfer pumps. The trial was performed in well T-1 for a week in November 2017 and successfully produced continuous oil with a stable rate of 1000 bbls/d. What makes this project unique is the continuous operation for a long period of time. Therefore, it is important to ensure the capacity of the gauge tank and the transfer pump compatibility with the rate from the well, the system durability which required routine inspection and maintenance to ensure the testing barge unit is in prime condition and to maintain vigilance and responsiveness of personnel. This project started in 2018 for several wells and the cumulative production up to January 2020 has reached 158 k bbls and will be continued as there are still potential oil resources to be unlocked. Innovation does not need to be rocket science. Significant oil recovery can be achieved with a simple approach considering all safety operation, production and economic aspect.

Breakthrough on Routine Service Cycle Time Improvement – Leap Frog Concept, Duri Field, Indonesia

Leap frog concept was created to address the loss of single joint rig agility and drive the cycle time average lower than ever. The idea is to move the preparation step into a background activity that includes moving the equipment, killing the well, dismantling the wellhead and installing the well control equipment/BOP before the rig came in. To realize the idea, a second set of equipment is provided along with the manpower. By moving the preparation step, the goal is to eliminate a 50% portion of the job from the critical path. The practice is currently performed in tubing pump wells on land operations. However, the work concept could be implemented for other type of wells, especially ESP wells. After implementation, the cycle time average went down from 18 hours to 11 hours per job, or down by ~40%. The toolpusher also reports more focused operations due to reduced scope and less crew to work with, making the leap frog operation safer and more reliable. Splitting the routine services into 2 parts not only shortened the process but it also reduces noise that usually appear in the preparation process. The team are rarely seen waiting on moving support problems that were usually seen in the conventional process. Having the new process implemented, the team had successfully not only lowered cycle time, but also eliminated several problems in one step. Other benefits from leap frog implementation is adding rig count virtually to the actual physical rig available on location, and also adding rig capacity and completing more jobs compared to the conventional rig. In other parts, leap frog faced some limitation and challenges, such as: limited equipment capability for leap frog remote team to work on stuck plunger, thus hindering its leap frog capability, and working in un-restricted/un-clustered area which disturb the moving process and operation safety.

No Wait-On-Cement (NO WOC) Successfully Applied in Pertamina Hulu Mahakam (PHM) and Creating Significant Well Rig Time Saving

As the new operator of the Mahakam Block started in 2017, Pertamina Hulu Mahakam (PHM) were challenged to ramp up operations in order to combat massive production decline. At the same time, reducing well cost was also a paramount importance to ensure that the economic targets of the wells were achieved following the reduction of well stakes. One of the remaining unsolved enigmas is how to achieve No Wait-on-Cement (NO WOC) on surface diverter section as this will create a lot of rig time saving both on single well and batch operations. The project begins with several different kinds of proposal until the best solutions were identified fulfilling safety, simplicity of operations and acceptable cost and finally were put in place with very satisfying results. The main key principle is conversion wellhead stages following well architecture while there were several modifications of casing hanger, adapter, additional materials & modified procedure. Rig time saving, additional operational gain and a promising new “breakthrough” of drilling technique become a significant impact of the successful effort. Now the method has become a standard in PHM operations and has already been integrated to SDI (Standard Drilling Instruction). The merit of this endless hard work could possibly be gained by other operators as it will create more added values both tangible and intangible.

Mahakam Field Characterization Using Production Type-Curve With Business Intelligence Application

Delta Mahakam is a giant hydrocarbon block which is comprised two oil fields and five gas fields. The giant block has been considered mature after production for more than 40 years. More than 2,000 wells have been drilled to optimize hydrocarbon recovery. From those wells, a huge amount of production data is available and documented in a well-structured manner. Gaining insight from this data is highly beneficial to understand fields behavior and their characteristics. The fields production characterization is analyzed with Production Type-Curve method. In this case, type curves were generated from production data ratio such as CGR, WGR and GOR to field recovery factor. Type curve is considered as a simple approach to find patterns and capture a helicopter view from a huge volume of production data. Utilization of business intelligence enables efficient data gathering from different data sources, data preparation and data visualization through dashboards. Each dashboard provides a different perspective which consists of field view, zone view, sector view and POD view. Dashboards allow users to perform comprehensive analysis in describing production behavior. Production type-curve analysis through dashboards show that fields in the Mahakam Delta can be grouped based on their production behavior and effectively provide global field understanding Discovery of production key information from proposed methods can be used as reference for prospective and existing fields development in the Mahakam Delta. This paper demonstrates an example of production type-curve as a simple yet efficient method in characterizing field production behaviors which is realized by a Business Intelligent application

Managing Oil and Gas Project Value By Prime (Pertamina Investment Management Engine)

Oil and gas companies are facing an enormous challenge to create value from mature fields. Moreover, price volatility presents a massive impact on project uncertainties. Therefore, robust portfolio management is essential for oil and gas companies to manage critical challenges and uncertainties. The objective of this study is to develop a robust portfolio model to assist top management in oil and gas companies to drive investment strategy. PRIME (Pertamina Investment Management Engine) has been built to visualize advanced oil and gas project portfolio management. The engine observes the relationship between risk-and-return as the main framework drivers. The profitability index is endorsed as a parameter to envisage the investment effectiveness of individual projects. Correspondingly, the risk index is a manifestation of multi-variable analysis involving subsurface uncertainty and price. A nine clusters "tactical board" matrix is provided as the outcome of PRIME to define generic strategy & action plans. The PRIME analysis leads to a dual theme of perspective: both macro and micro-scale. The macro-scale discovers a diversification of strategy and scenario development to achieve long-term objectives. Whereas, micro-scale perspective generates a detailed action plan in a particular cluster as a representation of the short and mid-term corporate strategy. Several strategies and action plans have been recommended, including advanced technology implementation, new gas commercialization, additional incentives in the Production Sharing Contract, tax management renegotiation, and project portfolio rebalancing

The Grobogan Mud Volcano Complex: An Identification to Reveal the Opportunity of Hydrocarbon Exploration

Mud volcanoes in Grobogan are referred as the Grobogan Mud Volcanoes Complex in Central Java where there is evidence of oil seepages. This comprehensive research is to determine the characteristics and hydrocarbon potential of the mud volcanoes in the Central Java region as a new opportunity for hydrocarbon exploration. The Grobogan Mud Volcano Complex consists of eight mud volcanoes that have its characteristics based on the study used the geological surface data and seismic literature as supporting data on eight mud volcanoes. The determination of geological surface characteristics is based on geomorphological analysis, laboratory analysis such as petrography, natural gas geochemistry, water analysis, mud geochemical analysis and biostratigraphy. Surface data and subsurface data are correlated, interpreted, and validated to make mud volcano system model. The purpose of making the mud volcanoes system model is to identify the hydrocarbon potential in Grobogan. This research proved that each of the Grobogan Mud Volcanoes has different morphological forms. Grobogan Mud Volcanoes materials are including muds, rock fragments, gas, and water content with different elemental values. Based on this research result, there are four mud volcano systems models in Central Java, they are Bledug Kuwu, Maesan, Cungkrik, and Crewek type. The source of the mud is from Ngimbang and Tawun Formation (Middle Eocene to Early Miocene) from biostratigraphy data and it been correlated with seismic data. Grobogan Mud Volcanoes have potential hydrocarbons with type III kerogen of organic matter (gas) and immature to early mature level based on TOC vs HI cross plot. The main product are thermogenic gas and some oil in relatively small quantities. Water analysis shows that it has mature sodium chloride water. This analysis also shows the location was formed within formations that are deposited in a marine environment with high salinity. Research of mud volcanos is rarely done in general. However, this comprehensive research shows the mud volcano has promising hydrocarbon potential and is a new perspective on hydrocarbon exploration.