New winch for the maintenance of deep offshore oil and gas wells

1987 ◽  
Vol 23 (11) ◽  
pp. 551-552
Author(s):  
L. I. Yakubovich ◽  
A. A. Imanov ◽  
A. G. Zokhrabov
2017 ◽  
Vol 158 ◽  
pp. 144-151 ◽  
Author(s):  
Zhi Zhang ◽  
Zeyu Zhou ◽  
Yufa He ◽  
Jianliang Zhou

1980 ◽  
Vol 102 (2) ◽  
pp. 82-91
Author(s):  
H. D. Beggs ◽  
J. P. Brill ◽  
E. A. Proan˜o ◽  
C. E. Roman-Lazo

Subsurface safety valves (SSSVs) are installed in offshore oil and gas wells to shut in the wells in case of pressure loss at the wellhead. The selection of these SSSVs requires prediction of the oil and gas flow rates at which the valve will close. A study was performed to improve the design criteria used in the selection. Improved correlations were developed to predict pressure drop across a SSSV as a function of flow rates, and the pressure drop at which a SSSV will close.


Author(s):  
Wen-Tsuen Wang ◽  
Lou Watkins

This paper describes a recently developed syntactic foam material designed to collapse under precisely defined conditions of temperature and pressure to protect ultra-deep high pressure offshore oil and gas wells. Each grade of syntactic foam is engineered to have a specific set of characteristics, tailored for the region of the well it occupies. In the startup phase, the materials remain intact, with no significant volume change. As pressure and temperature in the well rise during operations, the materials begin to compress and relieve pressure in the narrow, confined space of the annulus. Finally, when conditions reach preset limits, the syntactic foam undergoes a sudden and dramatic collapse, preventing excessive overpressure, and protecting the steel casing. An important advantage of this material is that it is passive, requiring no controls or active intervention. It responds automatically to protect the well casing from overpressures and temperature spikes. The properties of the material can be adjusted to suit a wide range of conditions inside a given well, or from one well to another.


2014 ◽  
Vol 11 (1) ◽  
pp. 131-138 ◽  
Author(s):  
Xiuquan Liu ◽  
Guoming Chen ◽  
Yuanjiang Chang ◽  
Lei Zhang ◽  
Weiguo Zhang ◽  
...  

2017 ◽  
Vol 39 (2) ◽  
pp. 413
Author(s):  
Letícia Ferraço de Campos ◽  
Pedro Mello Paiva ◽  
Pedro Paulo Gomes Watts Rodrigues ◽  
Maria Inês Paes Ferreira ◽  
Jader Lugon Junior

This paper presents computer modeling applied to the disposal simulation residual volume from offshore cementing unit, where the cement paste used by cementing operations of oil and gas wells. The software used was MOHID WATER with a lagrangian approach where the solid part of the residue was represented by conservative particles. It is able to assess the behavior of the solid part of the residue in the water column and its accommodation on the seabed. Future works using the Life Cycle Impact Assessment (LCIA) standard methods are considered to understand the results and the possible resulting harm to marine organisms.


2021 ◽  
Author(s):  
Yin Luo ◽  
Philippe Enkababian ◽  
Leah Hrab ◽  
Anas Najy ◽  
Ahmed Shokry ◽  
...  

Abstract With the expanding offshore rig activity in United Arab Emirates leading to an increased number of horizontal wells and longer drains, coupled with changing rock fabrics, it became imperative to diverge from the existing stimulation methods to deliver more consistent and reliable results. These results were achieved via the introduction of single-phase retarded acid (SPRA) and viscoelastic diverting acid (VEDA) to both active and shut-in wells offshore. The introduction of SPRA and VEDA was possible after extensive laboratory testing including core flow tests, solubility tests, emulsion tendency testing, and corrosion inhibition tests to evaluate and benchmark the performance of these blends in comparison to the existing acid recipes such as plain HCl and polymer-based diverted acid. These tests showed that a combination of SPRA and VEDA would allow maximizing lateral coverage and enhance acid penetration due to the reduced rate of reaction and chemical diversion capabilities from thief zones. Combining the introduction of SPRA and VEDA with a shift to bullheading and higher pumping rates enabled the delivery of previously unachievable production results at sustainable wellhead pressures or even well revival of shut-in wells. In addition, reduction of acid content for dolomite stimulation was possible due to the implementation of acid retardation, which also allowed protecting wellheads from exposure to higher acid concentrations while bullheading. Treatment parameters such as volumes, rates, and acid/diverter sequence and ratio were then adjusted for optimal wormhole penetration across all zones using a new carbonate matrix acidizing modeling software. Post-treatment evaluation for the cases of previously shut-in wells has proven the success of the SPRA and VEDA combination. Shut-in wells that were unable to produce sustainably at the required tubing-head pressure (production flowline pressure), were able to produce sustainably with a 100% increase in production compared to prestimulation testing. Similarly, for gas wells, the combination of SPRA and VEDA resulted in a 50% increase in production at a similar bottomhole pressure. In addition, water injectors have also exhibited sustainably increased levels of injectivity compared to prestimulation levels, leading to better sweepage. The novelty of this paper is the comparison between historical carbonate stimulation results in UAE using plain HCl acid with polymer-based diverted acid and using SPRA with VEDA. It also sheds light on the game-changing solutions that suit the ever-increasing challenges observed in offshore oil and gas wells including well placement, lithology, permeability contrast, and type of hydrocarbon within the various target sublayers.


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