Precise Bottom Hole Pressure Management to Reach Target Depth in a Narrow Windowed Ultra HP-HT Well: A Case for Automated Managed Pressure Drilling

2021 ◽  
Author(s):  
Ali Khalid ◽  
Qasim Ashraf ◽  
Khurram Luqman ◽  
Ayoub Hadj Moussa ◽  
Agha Ghulam Nabi ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Formation Pressure ◽  
Hole Pressure ◽  
Bottom Hole Pressure ◽  
Area Of Interest ◽  
Bottom Hole ◽  
Coastal Belt ◽  
Managed Pressure Drilling ◽  
Wellbore Pressure ◽  
Target Depth

Abstract With the energy sector in crisis the worldover, oil and gas operators continue to seek more effective and efficient methods to reach potential prospects. With sharply declining oil prices, it is imperative that operators minimize the non-productive time in the drilling of all wells. Many operators are actively seeking riskier exploration to establish a strong foothold in this volatile market. One such area of interest to operators is HPHT and beyond wells. An HPHT prospect carries a high-risk high-reward potential, therefore newer and advanced methods are being deployed to successfully drill and complete HPHT wells. The Makran Coastal belt in south western Pakistan is one such area containing a potential Ultra-HPHT prospect. Many operators had attempted to drill about 9 wells in the locality but never managed to reach target depth due to drilling operations being plagued with a large number of problems. The drilling problems included high pressure influxes, stuck pipe while controlling influxes, circulation losses with high mud weights and ECD’s, differential sticking against permeable formations, inefficient bottom hole pressure control due to mud weight reduction with high temperatures and swabbing from the formation due to having an insufficient trip margin. The operator was facing an extremely narrow drilling window in the target section. The maximum formation pressure was estimated to be around 2.29 SG while the maximum fracture pressure of the formation was estimated to be around 2.35 SG in EMW. It was abundantly clear that drilling with a conventional mud system would be impossible and impractical on all forthcoming wells. As it was of paramount importance to precisely manage the wellbore pressure profile, the operator decided to apply managed pressure drilling on a candidate well. By applying managed pressure drilling techniques the operator expected to drill the section with an underbalanced mud weight and maneuver the bottom hole pressure just above the pore pressure line and thereby avoid circulation losses, detect influxes early on and control influxes without the need of ever shutting in the well, account for mud density variations with temperatures by executing an advanced thermal hydraulics model in real time, mitigate swabbing from the formation again by maintaining a constant bottom hole pressure while tripping, and finally ascertain the downhole pressure environment by conducting dynamic formation pressure tests. The successful application of MPD enabled the operator to reach target depth for the first time in the history of the area. The paper studies the planning, design, and execution of MPD on the subject well.

Fully Automatic Managed Pressure Drilling Technology, The Answer to Weeks of Well Complications Including High Temp, Narrow Mud Window & CO2 Influx in Challenging Exploration Wells

2021 ◽  
Author(s):  
Muhammad Jamaluddin Muhammad ◽  
Carlos Iturrios ◽  
Abdallah Kadadha ◽  
Mojtaba Alqatari ◽  
Ayoub Hadj-Moussa
Keyword(s):  
Pore Pressure ◽  
Drilling Process ◽  
Formation Pressure ◽  
Hole Pressure ◽  
Bottom Hole Pressure ◽  
Bottom Hole ◽  
Managed Pressure Drilling ◽  
Fully Automatic ◽  
Gain Loss

Abstract Managed Pressure Drilling is an adaptive drilling technique used to precisely assess the formation pressure limits and manage the annular pressure profile accordingly. MPD uses a lighter mud density that with assistance of surface backpressure maintain the overbalance condition, and the dynamic adjustment of this surface pressure allows to maintain Constant Bottomhole Pressure (CBHP) in both dynamic and static conditions. Generally, MPD system reduces the extra overbalanced pressure applied on a formation while drilling conventionally Recently, the operator utilized Managed Pressure Drilling (MPD) Constant bottom hole pressure (CBHP) technique to drill a challenging HPHT gas well successfully through an exploration field. The case study field elaborates challenges of uncertain formation pressure, narrow pore pressure-fracture pressure window and high background gas readings leading to extreme well complications. These challenges were counteracted with the implementation of Managed pressure drilling MPD technology, enabling to drill a well without any complications. To coupe with the complications including high temperature, narrow mud window & CO2 influx, MPD technology was called to be utilized in the challenging exploration field. With the implementation of MPD in this exploration drilling campaign, the case study well proved to optimize the overall drilling process, hence proving an answer to the previous problems in the field. The subject well was the first well to reach this depth. As a starting point, the actual bottom hole pressure limitations were established by performing MPD pore pressure tests, due to the lack of data as the only other option was to rely on geo-mechanics interpretations which is not very accurate, considering the case study specifically. Being it an exploration field, the bottom hole conditions were inconsistent and uncertain. The fully automatic MPD system enabled real-time evaluation and instant adjustment of the bottom-hole formation pressure changes, throughout the drilling process. The precise and instant control of bottom-hole pressure was the key factor of the overall success, hence mitigating any well complications, which previously costed weeks of rig days and associated oil based mud costs during losses. Since MPD technique evaluates & optimizes the required mud weight, hence saving the unnecessary overbalance on the well which had been the cause of several problems previously like losses, differential sticking and ballooning. Furthermore, for these critical narrow window wells, there was a need of a fool proof gain/loss monitoring system to stay top of the game all times. The sophisticated early kick/loss detection feature of the MPD system added value to the operation, which was independent of the conventional rig mud pit transfers and mixing which usually trigger false gain/loss alarms. The narrow drilling window was exacerbated by the increase in annulus frictional losses for these extended wells. The approach of ‘Prevention is always better than cure’ was adopted by the operator, since MPD prevents/mitigates a lot of hazards before they happen. This publication summarizes the details of how the MPD CBHP technique, early kick detection system & instant control system made it possible to efficiently and successfully execute the drilling process safely. It was proved that real time monitoring, and instant reactions are necessary to be able to adjust the BHP to keep the well under control throughout the drilling and post drilling operations like reaming trip in these types of high gas bearing formations. Hence MPD enabled the drilling of complex geological and weak fracture strength formations without any NPT for well control situations with the few value-added benefits like improved ROP, extending the total depth by 1300 ft additional to the initial plan achieving the deepest TVD (true vertical depth) drilled in the field.

First MPD Project in Myanmar Successfully Completed on Deepwater Exploration Well

2021 ◽  
Author(s):  
Harpreet Kaur Dalgit Singh ◽  
Bao Ta Quoc ◽  
Benny Benny ◽  
Ching Shearn Ho
Keyword(s):  
Pore Pressure ◽  
Control Device ◽  
Back Pressure ◽  
Deepwater Drilling ◽  
Hole Pressure ◽  
Bottom Hole Pressure ◽  
Bottom Hole ◽  
Managed Pressure Drilling ◽  
Pore Pressure Prediction ◽  
Exploration Well

Abstract With the many challenges associated with Deepwater Drilling, Managed Pressure Drilling has proven to be a very useful tool to mitigate many hurdles. Client approached Managed Pressure Drilling technology to drill Myanmar's first MPD well on a Deepwater exploration well. The well was drilled with a Below Tension Ring-Slim Rotating Control Device (BTR-S RCD) and Automated MPD Choke System installed on semi-submersible rig, Noble Clyde Boudreaux (NCB). The paper will detail MPD objectives, application and well challenges, in conjunction with pore pressure prediction to manage the bottom hole pressure to drill to well total depth safely and efficiently. This exploration well was drilled from a water depth of 590m from a Semisubmersible rig required MPD application for its exploratory drilling due to uncertainties of drilling window which contained a sharp pressure ramp, with a history of well bore ballooning there was high potential to encounter gas in the riser. The Deepwater MPD package integrated with the rig system, offered a safer approach to overcome the challenges by enhanced influx monitoring and applying surface back pressure (SBP) to adjust bottom hole pressures as required. Additionally, modified pore pressure hunting method was incorporated to the drilling operation to allow more accurate pore pressure prediction, which was then applied to determine the required SBP in order to maintain the desired minimum overbalance while drilling ahead. The closed loop MPD circulating system allowed to divert returns from the well, through MPD flow spool into MPD distribution manifold and MPD automated choke manifold system to the shakers and rig mud gas separator (MGS). The automated MPD system allows control and adjustments of surface back pressure to control bottom hole pressure. MPD technology was applied with minimal overbalance on drilling and connections while monitoring on background gases. A refined pore pressure hunting method was introduced with manipulation of applied surface back pressure to define this exploration well pore pressure and drilling window. The applied MPD Deepwater technique proved for cost efficiency and rig days to allow two deeper casing setting depths and eliminating requirement to run contingency liners. MPD system and equipment is proving to be a requirement for Deepwater drilling for optimizing drilling efficiency. This paper will also capture detailed lesson learned from the operations as part of continuous learning for improvement on Deepwater MPD drilling.

Managed Pressure Drilling and Underbalanced Drilling Compounded Role in Solving the Exploration and Appraisal Challenges of Biogenetic Gas Resources in the United Arab Emirates -Case Study

2021 ◽  
Author(s):  
Ahmed Al Mutawa ◽  
Ibrahim Hamdy ◽  
Eias Daban Al Shamisi ◽  
Bassem El Yossef ◽  
Mohamed Sameer Amin ◽  
...  
Keyword(s):  
United Arab Emirates ◽  
Drilling Fluid ◽  
Productivity Index ◽  
Biogenic Gas ◽  
Hole Pressure ◽  
Bottom Hole Pressure ◽  
Underbalanced Drilling ◽  
Bottom Hole ◽  
Novel Approach ◽  
Managed Pressure Drilling

Abstract Biogenic gas resources have gathered importance recently due to its widespread availability, occurrence at geologically predictable circumstances, and existence at shallow depths. It is estimated that biogenic gas forms more than 20% of the global discovered reserves. However, the exploration and development of these unconventional resources come with numerous drilling and reservoir challenges. This paper showcases a novel approach used in the United Arab Emirates to overcome these challenges using managed pressure and underbalanced drilling. To tackle both reservoir and drilling challenges, a hybrid solution combining Underbalanced (UBD) and Managed Pressure Drilling (MPD) was applied. UBD was used to characterize the reservoir in terms of pressure and productivity index to ultimately enhance productivity by eliminating formation damage. MPD was used next to continue drilling through the problematic zone which had high instability due to the presence of highly sensitive salt, in addition to the presence of high pressure and loss zones. The fit for purpose hybrid application design allowed the operator to immediately switch between UBD and MPD conditions, as the well required with the same equipment. Three of the four targeted formations were in the 8 ½″ hole section, UBD was selected to drill the first reservoir formation which allowed pore pressure verification and avoided using excessive mud weight that was the culprit of many challenges like slow ROP, drilling fluid losses, bit balling, and fracking the formations. UBD has proved that mud weight can be reduced by 20%-30% comparing to conventional drilling. The second formation was a salt formation that has caused previously hole collapse and losses-kicks problems as heavy mud used to drill this salty formation. MPD used successfully drill this section by constant bottom hole pressure and lower mud weight as it was found from analyzing offset wells reports that hole collapse occurred at connections and pump off events. Constant Bottom Hole Pressure (CBHP) also eliminated tight spots and excessive reaming resulting in optimized drilling. The third formation used MPD as well to minimize overbalance pressure over previous sections while the fourth formation was drilled by UBD as it had a separate 6″ hole section as it formed an independent reservoir. The combined MPD and UBD approach eliminated most the NPT encountered in offset wells, enhanced Rate of Penetration (ROP) by 200% to 300% and slashed the well drilling time by 27 days.

Taking the Proper Action to Gas Influx during Constant Bottom-Hole Pressure Technique of Managed Pressure Drilling

2013 ◽  
Author(s):  
Mengjiao Yu ◽  
Ali Karimi Vajargah ◽  
Stefan Z Miska ◽  
Reza Majidi ◽  
Mehmet Evren Ozbayoglu
Keyword(s):  
Proper Action ◽  
Hole Pressure ◽  
Bottom Hole Pressure ◽  
Bottom Hole ◽  
Managed Pressure Drilling

Optimising Well Design in Saudi Arabia: Successful Application of Managed Pressure Drilling Enables Drilling Across Multiple Pressure Zones and Running Liner Using Constant Bottom Hole Pressure Technique

2014 ◽  
Author(s):  
Nelson O Pinero Zambrano ◽  
Ibraheem M Al-Ageel ◽  
Muhammad Abdul Muqeem ◽  
Abdulaziz Sallim Al Mutawa ◽  
Mohamed Cherif Mazouz ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Hole Pressure ◽  
Bottom Hole Pressure ◽  
Bottom Hole ◽  
Well Design ◽  
Managed Pressure Drilling

Dynamical Simulation of High-Pressure Gas Kick in Ultra-Deepwater Riserless Drilling

2020 ◽  
Vol 143 (6) ◽  
Author(s):  
Liangjie Mao ◽  
Mingjie Cai ◽  
Qingyou Liu ◽  
Guorong Wang
Keyword(s):  
High Pressure ◽  
Return Rate ◽  
Influx Rate ◽  
Well Control ◽  
Hole Pressure ◽  
Bottom Hole Pressure ◽  
Dynamical Simulation ◽  
Bottom Hole ◽  
Gas Kick ◽  
Wellbore Pressure

Abstract During riserless drilling for ultra-deepwater gas wells, well control challenges induced by high-pressure gas kick will be faced. A two-phase flow model with consideration of high-pressure gas invasion during riserless drilling was proposed, and the model was proved to be more accurate for predicting high-pressure gas kick during riserless drilling by reproducing field data and comparison with published models. Then, a dynamical simulation of high-pressure gas kick in ultra-deepwater riserless drilling was presented. Results showed that during ultra-deepwater riserless drilling, the bottom hole pressure will be underestimated, while pit gain will be over-estimated without considering the gas acceleration effect. With the consideration of gas acceleration effect at high-pressure well bottom, the gas influx rate increases rapidly with the kick time and tends to be stable after a period of time as negative pressure difference at well bottom increases. During riserless drilling, according to the timeliness and effectivity of kick detection methods, pit gain is prior for kick detection, following bottom hole pressure, standpipe pressure, and return rate. Moreover, if early gas kick was not detected, the rapid increase in change rate of standpipe pressure and return rate can be regarded as an indicator, showing that gas is reaching mud line. Besides, the effects of shutoff time, drilling displacement, drilling fluid density increases, geothermal gradient, and reservoir permeability on kick indicators and wellbore pressure have been discussed. The research results could provide important theoretical bases and technical guidance for well control aspects of riserless drilling.

Sign in / Sign up

Export Citation Format

Share Document