Evolution of Real-Time Operations Monitoring: From Concept to Global Implementation
Abstract: TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractThe unique challenges posed by deepwater wells of everincreasing complexity continue to force operators and service companies to explore new and innovative well delivery solutions. In early 2002, Shell Exploration and Production Americas took an important step towards well performance optimization with the initiation of a pilot study into real-time, remote monitoring of exploration and production wells in the Gulf of Mexico (GoM). Starting with a small-scale … Show more
Search citation statements
Paper Sections
Citation Types
Year Published
Publication Types
Relationship
Authors
Journals
Cited by 28 publications
References 12 publications
Background Over the past two decades Geomechanics has made substantial contributions to the petroleum industry in the following areas:○reducing well construction costs1,○maximizing production2, and○increasing the life of the well. Currently the industry is venturing into more complex extended reach wells3, deeper water, higher pressure higher temperature environments, sub-salt settings4, lower pore pressure/fracture gradient margins, depleted zones5, fractured carbonates2 and fractured reservoirs6, environmentally sensitive areas, and many other difficult to develop situations, as illustrated in Figure 1. Geomechanics will play a significant role in addressing these added challenges. The high price of oil is here for a long time. Our technical responsibility is to make sure that the unit development cost (UDC) to produce this oil is contained and subsequently lowered with aggressive application of relevant technology and a knowledgable workforce adept at applying this technology. Being prepared to deal with the following issues will be integral to success:○borehole (in)stability7–12,○lost circulation13,14,○stuck pipe15,○sand production16,17,○casing collapse18,19,○well failures20,○formation damage21,○sub-salt related issues2. Each of these problems can strike at any time if we are not vigilant and pro active in avoiding them. Prevention at the outset is more cost-effective than fixing these issues later. I propose we have to bridge the gap between people and technology to be effective in this age of oil industry geomechanics. See Figure 2. Controlling Costs Geomechanics-related issues cost the industry billions of dollars.22 We cannot afford, as an industry, to lose billions of dollars on Geomechanics-related non-productive time (NPT) and associated loss in revenues.32 Over the past decade, for the drilling industry on an average twenty two percent of the drilling budget can be attributed to wellbore related NPT. Fifty percent of this NPT is associated with geomechanics related (i.e. wellbore stability, Lost circulation, stuck pipe, etc.) issues.1, 8, 11, 22, 32 In spite of advances in technology, this NPT percentage associated with borehole related problems has not drastically changed over the past decade. NPT percentage of the total drilling budget is much too high and must be lowered to a more acceptable level. Also further scrutiny of the NPT data suggests a trend, that approximately 90% of costs can be attributed to a small percentage of wells that are highly complex. When these wells have problems, the cost escalates. See Figure 3. Hence, it is critical to manage the available geomechanics resources in the most optimal manner. It is important to identify the high mechanical-risk index wells and get the right geomechanics resources committed - both personnel and data collection - early in the planning stages of the well construction and utilize these resources throughout the well delivery cycle.
Background Over the past two decades Geomechanics has made substantial contributions to the petroleum industry in the following areas:○reducing well construction costs1,○maximizing production2, and○increasing the life of the well. Currently the industry is venturing into more complex extended reach wells3, deeper water, higher pressure higher temperature environments, sub-salt settings4, lower pore pressure/fracture gradient margins, depleted zones5, fractured carbonates2 and fractured reservoirs6, environmentally sensitive areas, and many other difficult to develop situations, as illustrated in Figure 1. Geomechanics will play a significant role in addressing these added challenges. The high price of oil is here for a long time. Our technical responsibility is to make sure that the unit development cost (UDC) to produce this oil is contained and subsequently lowered with aggressive application of relevant technology and a knowledgable workforce adept at applying this technology. Being prepared to deal with the following issues will be integral to success:○borehole (in)stability7–12,○lost circulation13,14,○stuck pipe15,○sand production16,17,○casing collapse18,19,○well failures20,○formation damage21,○sub-salt related issues2. Each of these problems can strike at any time if we are not vigilant and pro active in avoiding them. Prevention at the outset is more cost-effective than fixing these issues later. I propose we have to bridge the gap between people and technology to be effective in this age of oil industry geomechanics. See Figure 2. Controlling Costs Geomechanics-related issues cost the industry billions of dollars.22 We cannot afford, as an industry, to lose billions of dollars on Geomechanics-related non-productive time (NPT) and associated loss in revenues.32 Over the past decade, for the drilling industry on an average twenty two percent of the drilling budget can be attributed to wellbore related NPT. Fifty percent of this NPT is associated with geomechanics related (i.e. wellbore stability, Lost circulation, stuck pipe, etc.) issues.1, 8, 11, 22, 32 In spite of advances in technology, this NPT percentage associated with borehole related problems has not drastically changed over the past decade. NPT percentage of the total drilling budget is much too high and must be lowered to a more acceptable level. Also further scrutiny of the NPT data suggests a trend, that approximately 90% of costs can be attributed to a small percentage of wells that are highly complex. When these wells have problems, the cost escalates. See Figure 3. Hence, it is critical to manage the available geomechanics resources in the most optimal manner. It is important to identify the high mechanical-risk index wells and get the right geomechanics resources committed - both personnel and data collection - early in the planning stages of the well construction and utilize these resources throughout the well delivery cycle.
Re-development drilling at Shell's Ram Powell prospect in the Gulf of Mexico targets profitable delivery of remaining hydrocarbons present in lower-volume reservoir pockets. Marginal economics put a strong focus on efficient operations, which are complicated by the technical challenges posed by severely depleted reservoirs (up to 6,000 psi differential pressure) that can only be accessed by drilling extended reach (ERD) wells. Specific challenges that had to be overcome in drilling recent Ram Powell wells include negotiating very narrow drilling margins, preventing major non-productive time associated with well control, lost circulation and stuck pipe events, and drilling the wells at optimum efficiency and favorable economics. This paper discusses the integrated operational plan that the Ram Powell team employed to successfully drill four recent ERD development wells and two slim hole sidetracks through substantial depletion while becoming one of the best-performing offshore operational teams in Shell. Specific tactics discussed include:a fit-for-purpose hole cleaning program for ERD and depleted wells;a mud weight and ECD strategy that exploits the naturally existing stress cage;an effective method to raise fracture propagation pressures in case of losses in induced or natural fractures;the use of flat-rheology synthetic-based mud to minimize barite sag and reduce ECDs;addressing the underestimated effects of temperature, annular pressure fluctuations and exposure time on wellbore stability and lost circulation;contingencies to deal with well control issues during a catastrophic loss;dealing with detrimental vibrations during depleted sand drilling Introduction Further development of the mature Ram Powell prospect (Fig. 1) faces the same challenge as seen in many brown-field developments around the world: how to extract remaining hydrocarbons in place in low(er) volume reservoirs in a cost efficient way? The dilemma here is that whereas it is difficult - if not impossible - to justify high cost wells from an economical standpoint, rather complex wells are required to access the oftentimes poorly accessible reservoirs scattered about the prospect. Main elements of complexity are the extended reach character and associated directional complexity associated with these wells, as well as the fact that they are no longer drilled under pristine reservoir conditions. Usually, historical production has led to significant reservoir depletion, leading to significant changes in pore-pressure and associated geo-mechanical changes. The challenges we were faced with at Ram Powell were in many respects unique. Ram Powell was one of the very first deepwater developments in the Gulf of Mexico1,2. As a result, at Ram Powell we are further into the field's production lifecycle than in many other Gulf of Mexico prospects, experiencing drilling problems that have rarely been seen before or experienced in similar severity. Moreover, a unique challenge was presented to the team by making the number of wells to be drilled in the re-development campaign dependent on the well delivery execution efficiency achieved. Achieving operational excellence thereby translated directly in access to more drilling and production opportunities. In the following, we will highlight how the Ram Powell team met the above-mentioned challenges, achieving a high degree of operational proficiency that made it one of the best performing teams in Shell E&P Co. We will discuss the nature of depleted sands and the challenges associated with drilling them, and present the elements of the systems approach that was adopted to drill highly successful wells. Depleted Drilling Challenges at Ram Powell Brown Field development from fixed structures presents complex drilling and completion challenges. The first stage of production of the primary targets, usually better-developed and higher-volume reservoirs, has usually produced a significant level of depletion. Further reserve recovery now requires penetration of these depleted zones with drainage points at much greater step-out than the original wells. This is the situation we face at Ram Powell.
TX 75083-3836 U.S.A., fax 1.972.952.9435. AbstractVerifying pressure integrity of a casing string and the adjacent formation is an important requirement during drilling of a well. Crucial decisions on mud weight, kick tolerance, and the setting depth of the next casing string are based on the outcome of formation strength tests (FST) such as leak-off tests (LOT) or formation integrity tests (FIT). Moreover, government regulations usually require that a minimum integrity is guaranteed before a well may be deepened.Yet the majority of FSTs and their interpretation currently carried out in the field can only be characterized as inadequate. Commonly, FSTs lack quality and accuracy due to (in)sensitivity in the hydraulic system to subtle pressure effects in the wellbore, use of highly compressible synthetic or oil muds, non-linear thermal profiles, poorly-understood formation stress and strength behavior, or simply by poor data capturing (e.g. by hand-generated plots). This may have a significant negative impact on the drilling operation. For instance, when mud weight windows are incorrectly assessed after testing, lost circulation or well control problems may ensue on wells with tight drilling margins.Here, we highlight several of the problems underlying current FSTs and their interpretation, illustrating them with actual field examples (such as the discrepancy often observed between surface readings and downhole pressure-while drilling (PWD) readings obtained while testing), and show how test artifacts can be either avoided or accounted for. A case is made for the use of downhole recorded pressure data to correctly determine casing shoe strength.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
Contact Info
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Product
Resources
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.
