In April 2012, the world's first 16-in. solid expandable tubular (SET) liner was run to depth and successfully cemented and expanded. The installation of the large diameter liner marks a significant shift in the application of expandables from deeper contingency applications to planned hole-conservation designs in the upper wellbore. The purpose of the installation was zonal isolation. In Saudi Arabia, the Uthmaniyah field, the prolific Arab D reservoir has been produced for many years, resulting in lower pore pressures than the shallower Arab A, B, and C reservoirs. Due to the differences in pore pressure, isolation between the Arab D and Arab A, B, C reservoirs is required to efficiently drill some of these wells. The 16 × 18-5/8-in., 115 lb/ft open hole liner (OHL) system isolated the Arab D reservoir by covering the Arab A, B, and C reservoirs while minimizing the loss of hole diameter to maintain the original wellbore design and drilling tools. Both objectives were safely and successfully achieved with the running and expansion of 1,708 ft (pre-expanded length) of 16-in. solid expandable pipe, hung as a liner and anchored into the 18-5/8-in. casing. To isolate the pressure differential, the 16-in. SET liner was installed in a negative pressure environment. Once the liner was installed, the mud weight was reduced to drill the lower pressure Arab D reservoir and the remainder of the hole section. From a reservoir management viewpoint, this installation eliminated cross flow from the higher pressure Arab A, B, and C into the Arab D reservoir, thus preserving the pressure regime of the oil producing Arab D. Additional benefits of the 16-in. expandable liner included an increase in ROP in the hard rock environment, the elimination of two-stage cementing requirements and the associated risk of stage tool failure, and reduction of hook load requirements associated with large, long casing strings.

The importance of improving the efficiency of drilling operations in the E&P industry cannot be overemphasized, since it directly impacts the overall cost of constructing oil and gas wells. The key performance indicator (KPI) for measuring drilling efficiency is feet per day (ft/d). In Saudi Aramco, a high level target KPI is normally generated separately for new development oil wells and gas wells, using a benchmark (BM) method based on actual and projected performance. The drilling teams found it difficult to relate individual well performance to the high level KPI target and were unable to properly strategize to improve performance. A new method, the field specific KPI, was developed to complement the BM method and provide a more user-friendly platform to manage performance. Notable impacts of the new method include; improved planning, accurate monitoring of performance for prompt corrective action; and enhanced accountability and variance analysis from individual wells to fields, departments and the high level. These were demonstrated to be the prime drivers to improve performance. This paper presents the process of generating the drilling performance efficiency KPIs using the existing BM method and the new field specific method. The scope, strengths, benefits and weaknesses of both methods are also addressed.

In the present paper, directional drilling job failures were carefully analyzed for the period 2014 and 2015 in wells drilled in the Kingdom of Saudi Arabia. The focus of the study was to evaluate the performance and efficiency of the Positive Displacement Motors (PDM) and Rotary Steerable Systems (RSS) during drilling operations. The data was collected from Saudi Aramco database and limited to wells that used PDM and RSS as a directional drilling system. A total of 7772 runs were reviewed and the information was classified according to tool size, number of runs, operating time, lost time, number of failures and hole size. A detailed and comprehensive study was conducted individually for each run that a PDM and RSS was used, reviewing daily drilling reports and analyzing the performance and efficiency of the PDM and RSS in drilling operations across the Kingdom of Saudi Arabia. Focusing on PDM failures, it was observed that 45.41% of the problems occurred before 50 hours of operating time. In the case of RSS, the study revealed that 49.59% of the failures occurred before 50 hours of operating time. The causes of the failures were a combination of different factors such as vibration, temperature, type of drilling fluids used and reservoir properties such as H2S and CO2 content. The PDM average operating time remained almost the same (77 hours to 78 hours from 2014 to 2015), moreover the efficiency improved from 95.37% to 96.94% (1.64% improvement). The RSS average operating time dropped from 103 hours to 97 hours from 2014 to 2015, a reduction of 5.83%. The efficiency improved from 88.78% to 90.83% (2.30% improvement). The study concluded that the reduction of the operating time can lead to a higher efficiency on the PDM and RSS and this can be achieved by replacing these tools on every trip and performing preventive maintenance after each run. Also, improving the drilling parameters and durability of the directional drilling system will improve their performance and efficiency. The research became a useful reference to analyze the performance and efficiency of PDM and RSS Systems across Saudi Arabia's drilling operations. Directional Drilling Service Companies are encouraged and challenged to improve the performance, efficiency, and durability of their drilling tools.

One of the major challenges the Oil and Gas Industry faces nowadays during drilling operations is the twist-offs on Bottom Hole Assembly (BHA) components such as Drilling Jars, Shock Tools, Mud Motors, Roller Reamers, Stabilizers, Drill Collars, PBLs, Heavy Weight Drill Pipe (HWDP), Drill Pipe (DP), etc. To overcome this challenge, an initiative was proposed by performing a study based on twist-offs experienced on BHA components while drilling operations and recommendations are provided to reduce and eliminate twist-offs related to drilling with suboptimal drilling parameters. The statistical data for the twist-off events was collected coming from Daily Drilling Reports, and the analysis was limited to all wells which presented twist-offs on the drillstring and BHA components. Three examples of twist-offs due to drilling with erratic torque are discussed as well as a successful example of drilling parameters optimization. The three examples which presented drillstring and BHA twist-offs were analyzed using available BHA Dynamics and vibrations software and it was discovered that the parameters utilized (operational RPM) fell within the critical zone shearing force peaks (resonance vibrations). The components with the most twist-offs were identified. The hole size where we have the most twist-offs were also identified, which will help in focusing on these areas for the recommendations provided. This analysis will help Drilling Engineers and Foremen to foresee vibration dysfunctions and act accordingly by the use of available BHA Dynamics software in order to optimize drilling parameters before and during drilling. By drilling within a safe operating RPM window (away from resonant RPM), there will be reduction in the number of twist-offs and associated lost time.

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractA major Middle Eastern operator has been exploiting long reach, openhole, multi-lateral technology to maximize oil recovery from a large field producing from a limestone reservoir. Significant production increases have been attained, but the recovery efforts have been hampered by an inability to re-enter openhole sidetracks for remedial purposes. The operator has also encountered water production problems with no real way to identify the source of the water or to remediate it if the source is found. These problems have been overcome with the introduction of solid expandable tubulars in combination with intelligent well technology. An openhole multi-lateral involves sidetracking out of the main bore while in the open hole. In wells where the technology has been applied, production rates have generally been higher and recovery has improved. A lower unit development/operating cost is also a key driver in this type of well. The new adaptation of using solid expandable tubulars and intelligent well technology allows for re-entry into the lateral for remedial work and real-time pressure, temperature and flow data without the need for well intervention. Intelligent well components allow for quick identification of any water-producing zones and provide a means for shutting off the water production, again without the need for well intervention.This paper describes the deployment and operation of the new combined-technology application and presents field examples of its use. The paper also discusses applications under development that will push solid expandable tubular technology even further.