Take a quick look at some of the data points shaping upstream headlines and the movement of oil supplies around the world. A fluid technology has been developed to deposit a thin, impermeable barrier over the pores and microfractures of weak, underpressured, and otherwise troublesome formations to maintain wellbore stability and reduce formation damage.
Attendees do not require any tools for this course but a basic understanding of how a well is constructed and then operates as a producer or injector is very beneficial. This highly visual and interactive training welcomes delegate participation and questions. Delegates will leave with a better understanding of how important sharing information about a wells construction and operation can be, and how critical it is to document how the well operates and particularly any characteristics that are shown when the well is operating out of character. All persons will be given a PDF copy of all slides.
Petroleum geomechanics is defined as the interaction between the evolving earth stresses and the overburden and reservoir rock mechanical properties. A comprehensive understanding of rock mechanical behaviour is key to successful field appraisal and development. For example, 70% of the world’s oil and gas reserves are contained in reservoirs where rock failure and sand production will become a problem at some point. Wellbore stability issues have been estimated to cost the industry USD 8 billion annually. Around 80%–90% of data comes from “traditional” core and log petrophysics, but the importance of data quality control and a rigorous and consistent petrophysical interpretation is often overlooked by well construction and production engineers.
The course addresses the holistic sand management strategy implementation from geomechanics perspectives, through evaluation and implementation of appropriate solutions for minimisation of well costs and maximisation of reservoir productivity. It will look at the inter-relationships between geomechanics and operations, application of geomechanics in relation to sand production and completions, and show how geomechanics can be best applied to provide maximum value in sand management and life-of-well and field operations. The course comprehensively covers geomechanics and operational-related sand production mechanisms, laboratory simulations of sand production to provide measurement data for model calibration and validation, state-of-the-art analytical and 4-D numerical sanding predictive methodologies for life-of-well and field including scale effect, rock strength properties reduction associated with water-cut and estimation of cumulative sand volume and rate of sand production, and optimal mitigation and management of sand production taking into consideration the feasibility of deferment or elimination of sand control installation. The course is illustrated with field examples. Application of geomechanics in relation to sand production and completions in order to provide maximum value in sand management and life-of-well and field operations.
This course is an introduction to well integrity, its history, its barriers and how to apply it to wells using guidelines, standards and regulations. Following the material selection process, it goes into well construction, completion concepts and Christmas trees. Several concepts will be introduced including well operating envelope description, well handover and operate phase, well problems, change management, case studies and well abandonment. The practical course looks at a wide range of well issues and is based on the instructor's global experience. Attendees will be able to understand well problems, understand the value of data in the diagnosis and solution process, use a range of tools and techniques that will provide support for risk assessments and solutions, and deal with problems in a cost effective way.
This course probes well integrity questions with analytical models embedded in fluid flow and heat transfer principles. Attendees will learn the principles of analytical tools that enable us to diagnose and seek remediation of wellbore safety issues. This one-day training course emphasizes fundamental understanding of fluid- and heat-flow principles leading to improved production operation practices. Beyond those necessary parameters, the input of accurate flowing fluid temperature due to Joule-Thompson effect becomes equally important. To that end, both APB and SCP analyses are discussed.
Hydrocarbons are trapped at great depths with pressure and temperature higher than surface conditions which would vary depending on reservoir properties. When the well is set on production, these hydrocarbons travel through the wellbore over reducing geothermal and formation pressure gradients. Hence, at shallower depths the temperature drops below the cloud point and sometimes, below pour point of crude thus creating an ambient temperature for the formation of wax and deposition of paraffin on the inner side of production tubing.
It has been observed that when hot fluid passes through a pipe which is covered by a continuously circulating hot water bath, the temperature difference of the fluid at surface outlet and sub-surface reservoir is reduced to a minimal value. This paper therefore proposes a practical application of such heat transfer within a wellbore for passively solving major industrial issues of paraffin depositions. The idea lies in minimizing the heat losses, which can be effectively done by insulating the inner side of the casing so that the annulus and fluid flowing within the tubing is isolated from exterior losses. According to the First law of Thermodynamics the fluid flowing within the tubing will experience reduction in thermal gradient. These loses can be compensated by injecting hotter brine through a pipe at the bottom of the annulus, which is isolated, using production packer. Further, circulating hot fluid in the annulus would result in isothermal heating of the fluid flowing through the tube which would minimize the heat loss across tubing, causing an increase in temperature of fluid at the surface above pour point. Several researchers have put forth heat transfer equations across the tubing's, annulus, insulator, casing, cement and the formation which can be used to calculate the overall heat transfer coefficient and thus, the amount of heat losses. Quartz sensors placed at the bottom of a wellbore would detect bottom borehole temperature based on which the injection temperature of fluid can be manipulated. The entire process can be automated by applying an artificial intelligent system which would monitor, control and respond. This method would increase the capex but would decrease the operating cost thus leading to an increase in the life of the well.
The key objective of this study was to develop a high resolution wellbore stability model for planned highly inclined development wells of an ultra-deepwater field through integrating geological, geophysical, petrophysical and drilling data to design optimized drilling mud weight window.
This study describes a customized high resolution wellbore stability modelling process for development wells in ultra-deepwater setting, where shale and sandstone have different pore pressure and stress magnitudes. Un-calibrated and calibrated seismic velocities along with offset well data were used to generate the high resolution pore pressure model for the overburden shale section. Laboratory based geo-mechanical tests, petrophysical logs and offset well events were integrated for the estimation of sub surface stresses and rock mechanical properties for overburden shale and sandstone. Subsequently, separate wellbore stability model was built to estimate the shear failure gradient for overburden shale and sandstone.
This study suggests that the mud weight (MW) window in the overburden is primarily governed by two parameters – (i) sand-shale pressure equilibrium state, and (ii) stress anisotropy. The intervals where the sand and shale are not in pressure equilibrium state (i.e. shale pressure > sand pressure), the minimum MW requirement is defined by either pore pressure or shear failure gradient (SFG) of shale formation. Whereas, maximum limit is marked by fracture gradient of relatively less pressured sand formation. Therefore, in such intervals mud weight window becomes much narrower (~1 ppg) than those intervals where sand and shale is in pressure equilibrium (~1.6 ppg). This study also highlights the increase of minimum MW requirement (SFG) in some intervals having relatively higher stress anisotropy. The minimum MW requirement within the main reservoir section having thin intra-reservoir shale is controlled by the SFG of the sand formation, as strength is lower in the reservoir sand than intra-reservoir shale. Results show the importance of high resolution modelling in order to capture pressure uncertainty, thin sands, sand/shale pressure equilibrium state, stress anisotropy and its effects in defining the optimum mud weight window. Based on analysis, further risk zonation was done to highlights intervals prone to wellbore collapse and mud loss.
This paper illustrates how the integrated high resolution wellbore stability modeling would help in optimum mud weight planning for highly deviated / horizontal wells to minimize the drilling risks and non-productive time (NPT), especially for challenging field development settings (deepwater, ultra-deepwater, high stress, High pressure High temperature).
Wellbore integrity is very critical in oil and gas industry and needs to be maintained through the entire cycle of well's life. The most important item for well integrity is to set cement between two casings or between casing and formation. A good cement job provides isolation and protection for the well and a poor cement job can have cracks and allows corrosive fluids to migrate through micro channels.
Downhole casing repair is a common workover operations worldwide, especially in wells that have been producing over number of years. It is very challenging to control corrosive fluid migration which slowly corrodes casing and tubing over time. An innovative epoxy resin formulations has been developed and tested in the field to repair casing leaks which is extremely easy to handle and very economical. A cost-effective workover program can be developed and implemented depending on the severity of the leak.
The improved approach of using innovative resin can be used by mixing with cement blends to repair major casing damage and can also be used as standalone application to fix minor leaks. The system maintains extremely good rheological properties even when mixed with cement. The system has ability to withstand high differential pressure and is also resistant to acid, salts, hydrocarbons and most importantly various corrosive liquids. The precise application is determined by measuring the injectivity of the well. In the low injectivity wells, only epoxy resin solution will be spotted and repair the damaged casing. In the high injectivity wells, the chemical will be mixed with cement and completely seal the damaged zone. The chemical will enhance the mechanical properties of the cement and will be more resilient to extreme down-hole condition.
The paper will emphasize the added value and potential of the method in restoring the casing integrity. The paper will also discuss the laboratory test reports and application which will highlight effective and economical outcome.