scholarly journals The effect of lightweight agents on the density of cement slurry applied during oil and gas well drilling

Author(s):  
A S Bubnov ◽  
V S Khorev ◽  
I A Boyko
2021 ◽  
Vol 1064 (1) ◽  
pp. 012059
Author(s):  
R R Gazizov ◽  
A P Chizhov ◽  
V E Andreev ◽  
A V Chibisov ◽  
V V Mukhametshin ◽  
...  

2021 ◽  
Author(s):  
Ajita Ang C K Ang ◽  
Avinash A Kumar Kumar ◽  
Syazwan B A Ghani Ghani ◽  
Nann N N Maung Nann ◽  
M Hanif Yusof Yusoff ◽  
...  

Abstract Infill well drilling was planned and executed to increase production in a significantly depleted field. A total of 3 infill wells were drilled in 2 different layers of reservoir for an offshore operator in Myanmar. In the offset wells, water production had become significantly higher throughout. Previously all offset wells in this field were completed with open hole sand screens was chosen to isolate the water bearing sand in the sand reservoir below. Pore pressure prognosis were calculated from offset well depletion rate. Reservoir formation properties is assumed to be same throughout the field. The first well was drilled and was found that there were two gas water contacts through the 3 targeted sand layers. The gas water contact and WUT (Water Up To) in this well were unexpected and it was prognosed that these gas water contact are there due to compartmentalization. The 7" liner were set and cemented throughout these reservoirs. The cement job went as per the plan and there were no losses recorded during cementing. However, initial cement log did not show isolation. 2 more runs of cement log were performed 6 days and 10 days later while conducting intervention activities on other wells. All three cement log came to the same conclusion, showing no isolation throughout the annulus of the 7" production liner. Significant amount of gas had percolated into the annulus over time. Despite no evidence of poor cement slurry design observed during running various sensitivity studies and post-job lab tests final cement log, which was conducted under pressure and confirmed no hydraulic isolation. A cement remedial job was planned and an investigation was conducted to identify the plausible root causes. This paper explains on the root causes of poor cement presence in the annulus, and the remedial work that took place to rectify the issue.


Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6318
Author(s):  
Mahmoud Khalifeh ◽  
Larisa Penkala ◽  
Arild Saasen ◽  
Bodil Aase ◽  
Tor Henry Omland ◽  
...  

During drilling of petroleum or geothermal wells, unforeseen circumstances occasionally happen that require suspension of the operation. When the drilling fluid is left in a static condition, solid material like barite may settle out of the fluid. Consequently, the induced hydrostatic pressure that the fluid exerts onto the formation will be reduced, possibly leading to collapse of the borehole or influx of liquid or gas. A possible mitigation action is placement of a gel pill. This gel pill should preferably be able to let settled barite rest on top of it and still transmit the hydrostatic pressure to the well bottom. A bentonite-based gel pill is developed, preventing flow of higher density drilling fluid placed above it to bypass the gel pill. Its rheological behavior was characterized prior to functional testing. The designed gel pill develops sufficient gel structure to accommodate the settled barite. The performance of the gel was tested at vertical and 40° inclination from vertical. Both conventional settling and the Boycott effect were observed. The gel pill provided its intended functionality while barite was settling out of the drilling fluid on top of this gel pill. The barite was then resting on top of the gel pill. It is demonstrated that a purely viscous pill should not be used for separating a high density fluid from a lighter fluid underneath. However, a bentonite or laponite gel pill can be placed into a well for temporary prevention of such intermixing.


2014 ◽  
Vol 997 ◽  
pp. 713-716
Author(s):  
Pu Liu ◽  
Hu Yin ◽  
Tian Xiang Wang ◽  
Meng Han Si

With narrow Density Windows wells and high pressure oil and gas well drilling growing in number, the kick risks becoming increasingly prominent and higher requirements for well control technology being needed, the manage pressure drilling (MPD) technology is used more and more widely. The problems like how to effectively find gas overflowand how to effectively control the overflow in the MPD must be solved.Well must be shuted timely in conventional drilling when overflow happens.The special characteristics of overflow control equipment determines the diversity and effectiveness of its overflow monitoring means in MPD, and the overflow is found more effectively and timely than conventional drilling. Well control risk will increase sharply if kick cannot be timely and effectively identified and controled when overflow occurs. MPD can quickly adjust the wellhead back pressure and inhibit the formation fluid further invasion. Therefore, combining with MPD process and the fluid pressure parameters, the article establishs process of kick recognition and kick control, analyses of the process and analyzes and evaluates the pressure response in process of kick control.MPD can better control the bottom hole pressure in well control situation, ensuring drilling safety. The process of kick recognition and control is of great significance to promote the development and application of kick control technology in MPD.


2009 ◽  
Author(s):  
Florian Albert ◽  
Alexander Grimm ◽  
Michael Schmidt ◽  
Alain Cournoyer ◽  
Martin Briand ◽  
...  

2019 ◽  
Vol 9 (1) ◽  
pp. 3859-3862 ◽  
Author(s):  
R. Iqbal ◽  
M. Zubair ◽  
F. Pirzada ◽  
F. N. Abro ◽  
M. Ali ◽  
...  

Drilling mud density is an important factor in drilling operations. The cost of the drilling mud used for oil and gas well drilling can be 10%-15% of the total drilling cost, and the deeper the well, the more the needed drilling mud. This research aims to prepare a mud that provides performance similar to the conventional mud and to lower down the dependency of primitive CaCO3 technology by exploring it from trash/polluted and naturally occurring materials. For that purpose, a mud was prepared by replacing primeval CaCO3 with the CaCO3 derived from eggshells, as eggshells contain CaCO3 in high amounts which range from 70% to 95%. The success of this project will provide an affordable solution and an alternative way to explore new methodologies for obtaining CaCO3. According to the 2017 Report of Pakistan Poultry Association (PPA) 18,000 Million table eggs are consumed per year in Pakistan. The obtained results of this research are quite satisfactory. CaCO3 obtained from eggshells is used in high amounts, 275–410g to achieve density ranges from 9.5 to 11.0 pounds per gallon whereas, pure the needed quantity of pure CaCO3 is 150g to obtain the density of 10.5 pounds per gallon. Apart from this, it is also observed that eggshell based CaCO3 samples are more efficient in rheological properties compared to the market samples of CaCO3 t. The pH of pure CaCO3 sample of 10.5 pounds per gallon density is almost the same with the sample of eggshell CaCO3 of 10.5 pounds per gallon density.


Sign in / Sign up

Export Citation Format

Share Document