Search citation statements
Paper Sections
Citation Types
Year Published
Publication Types
Relationship
Authors
Journals
A new Acoustic Telemetry System (ATS) that obtains realtime bottomhole pressure and temperature data without the use of wireline has been introduced to the oilfield. Traditionally, wireline has been used to acquire bottomhole surface read-out (SRO) data in real time during well-test operations using either a wireline-deployed downhole inductive system or a download probe in close proximity to the transmitting device operations. The operational hazards possible when using wireline in deep water subsea safety systems have increased safety risks in certain applications. This paper discusses a new system that uses acoustic telemetry and operates with either down-hole latching or with a download probe located in close proximity to the transmitting device. The system was designed for land rigs, offshore jack-up rigs, and deepwater floating rigs. In addition to wireless data transmission to surface, the system has downhole memory gauges that record data independent of the real-time SRO interval rates. The system is also capable of bi-directional acoustical communication, which allows commands to be sent from surface to operate downhole instruments. The quality of data compares excellently with downhole memory gauge data. Other operational advantages of the system include the fact thattesting equipment can be in the well prior to firing the perforating guns,reduced rig time can reduce operational costs, andpersonnel and environmental safety are increased. In case of transmitting the data via the wall of the testing pipe, there is no need for a probe or latching device. The two case histories, which are presented in this paper, will describe system use and will verify its advantages. Introduction A major operator in South America wanted to test two wells and reviewed the currently available systems. The two wells were in two types of environments; i.e., one was onshore, and the other was a deepwater well. One of the primary advantages of the ATS system was that since the it would allow data transmission via wireline or via the wall of the testing pipe, the latching device could be eliminated. This factor was particularly important since it would eliminate any potential problems that could occur if the probe were to become stuck in the latch or mechanically fail. The system was designed so that it could operate with either downhole latching or with a download probe located in close proximity to the transmitting device. In addition to wireless data transmission to surface, the system also had downhole memory gauges that could record data independent of the real-time SRO interval rates. The land application called for the use of the system in a well with 1142 m, reservoir depth of 936 m and temperature of 110 °F. The off shore application was for a well with 1,332 m water depth, 3,700 m reservoir depth and 190°F bottomhole temperature. The operator decided to use the new system for both wells to reduce the possibility of catastrophic events inherent to wireline (SRO) as well as to compare the efficiency of the new concept to the previously used data acquisition methods such as downhole quartz memory gauges. Background The previously used SRO systems required inductive or mechanical downhole latch mechanisms to communicate and transfer bottomhole information to the surface. These systems required wireline as a physical medium to transmit the data. Over the last decade, however, the increased global hydrocarbon needs have driven the industry to explore development of deeper, higher capacity wells, and in these environments, safety issues concerned with handling well effluents and control fluids in the increased depths as well as the use of wireline became more difficult to address. During the 1980s and 1990s, intermediate SRO systems that used electromagnetic proximity probes were developed. Unfortunately, the primary constraint in all these systems was the use of wireline-deployed signal pick-up probes.
A new Acoustic Telemetry System (ATS) that obtains realtime bottomhole pressure and temperature data without the use of wireline has been introduced to the oilfield. Traditionally, wireline has been used to acquire bottomhole surface read-out (SRO) data in real time during well-test operations using either a wireline-deployed downhole inductive system or a download probe in close proximity to the transmitting device operations. The operational hazards possible when using wireline in deep water subsea safety systems have increased safety risks in certain applications. This paper discusses a new system that uses acoustic telemetry and operates with either down-hole latching or with a download probe located in close proximity to the transmitting device. The system was designed for land rigs, offshore jack-up rigs, and deepwater floating rigs. In addition to wireless data transmission to surface, the system has downhole memory gauges that record data independent of the real-time SRO interval rates. The system is also capable of bi-directional acoustical communication, which allows commands to be sent from surface to operate downhole instruments. The quality of data compares excellently with downhole memory gauge data. Other operational advantages of the system include the fact thattesting equipment can be in the well prior to firing the perforating guns,reduced rig time can reduce operational costs, andpersonnel and environmental safety are increased. In case of transmitting the data via the wall of the testing pipe, there is no need for a probe or latching device. The two case histories, which are presented in this paper, will describe system use and will verify its advantages. Introduction A major operator in South America wanted to test two wells and reviewed the currently available systems. The two wells were in two types of environments; i.e., one was onshore, and the other was a deepwater well. One of the primary advantages of the ATS system was that since the it would allow data transmission via wireline or via the wall of the testing pipe, the latching device could be eliminated. This factor was particularly important since it would eliminate any potential problems that could occur if the probe were to become stuck in the latch or mechanically fail. The system was designed so that it could operate with either downhole latching or with a download probe located in close proximity to the transmitting device. In addition to wireless data transmission to surface, the system also had downhole memory gauges that could record data independent of the real-time SRO interval rates. The land application called for the use of the system in a well with 1142 m, reservoir depth of 936 m and temperature of 110 °F. The off shore application was for a well with 1,332 m water depth, 3,700 m reservoir depth and 190°F bottomhole temperature. The operator decided to use the new system for both wells to reduce the possibility of catastrophic events inherent to wireline (SRO) as well as to compare the efficiency of the new concept to the previously used data acquisition methods such as downhole quartz memory gauges. Background The previously used SRO systems required inductive or mechanical downhole latch mechanisms to communicate and transfer bottomhole information to the surface. These systems required wireline as a physical medium to transmit the data. Over the last decade, however, the increased global hydrocarbon needs have driven the industry to explore development of deeper, higher capacity wells, and in these environments, safety issues concerned with handling well effluents and control fluids in the increased depths as well as the use of wireline became more difficult to address. During the 1980s and 1990s, intermediate SRO systems that used electromagnetic proximity probes were developed. Unfortunately, the primary constraint in all these systems was the use of wireline-deployed signal pick-up probes.
Proposal Testing to evaluate the potential of a new well or field is a common practice in the oil and gas industry. When performing this task in a deep-water environment, the operator and service company must address the special needs of the testing environment, and when testing a heavy oil reservoir, the challenges are even further exacerbated. Special consideration must be given to the following issues:High rig rates associated with deep-water operations will make job problems more costly.Producing heavy crude oil to surface, moving it through the surface production train, and finally, disposing of it in an environmentally acceptable mannerExposing the crude to an extended period of heat loss and low temperatures while it is in the landing string. In order for the well test to be effective, all the above conditions must be fully understood and methodology employed that will reduce the chance that operational risks will occur. This paper will discuss the successful testing of a heavy oil reservoir in deep water. A number of different ways to assist the production of heavy crude in the deep-water environment will be presented, and the relative merits and limitations of each will be considered. The discussion will provide an outline of the necessary additions to the surface production train and the use of chemicals and heat to ensure flow. Finally, the paper will consider what equipment is necessary to properly dispose of the produced fluid. The testing methods discussed in this paper can be applied to heavy- and low-pour-point crudes in deep water. The equipment and methods can also be used in shallow water applications or on land. The case history data will illustrate:Why particular methods and equipment were used and why others were rejected.The success of the methods selected to address the testing needs.What conditions are inherent when testing deepwater reservoirs in heavy oil, and what is required to nullify or reduce the impact from these conditions on testing operations.The lessons learned from the jobs. Improvements that could be made to further facilitate testing of heavy oil in a deep-water environment.How careful planning can overcome the testing problems in deep water for both low- and heavy-pour-point oils. The information will show that employing proven methods and the proper equipment enables successful testing with reduced risk in difficult heavy- and low-pour- point reservoirs. Introduction For purposes of this paper, heavy oil is defined as any petroleum with an API gravity of less than 20 degrees or a high specific density. In many cases, this type of crude will contain significantly large amounts of impurities and will have constricted flow properties due to its inherent high viscosity. Waxes often are a significant component and contribute to difficulties in flow. Production of heavy or low-pour-point oils typically is more difficult and more expensive than with lighter oils. This fact is particularly true when it comes to short-term, temporary operations such as well testing. Well testing in deep water exposes produced crude to a long period of time in a low-temperature environment that starts at the seabed and extends to the rig-mounted surface production package. Water temperature at the sea floor is often in the 35° F range. In addition, space constraints on exploration rigs may impact the configuration, size, and volume of the production equipment that is selected. A further complication is the fact that many of the reservoirs in this category are also unconsolidated. The difficulties associated with testing these wells can be divided into three broad categories:Flowing or producing the wellSeparating the fluids and measuring the flow ratesDisposing of produced fluid. There are other issues that do not really fall into these categories, but because of their significance, they will be discussed also.
Stress wave-based communication has great potential for succeeding in subsea environments where many conventional methods would otherwise face excessive difficulty, and it can benefit logging well by using the drill string as a conduit for stress wave propagation. To achieve stress wave communication, a new stress wave-based pulse position modulation (PPM) communication system is designed and implemented to transmit data through pipeline structures with the help of piezoceramic transducers. This system consists of both hardware and software components. The hardware is composed of a piezoceramic transducer that can generate powerful stress waves travelling along a pipeline, upon touching, and a PPM signal generator that drives the piezoceramic transducer. Once the transducer is in contact with a pipeline surface, the generator integrated with an amplifier is utilized to excite the piezoceramic transducer with a voltage signal that is modulated to encode the information. The resulting vibrations of the transducer generates stress waves that propagate throughout the pipeline. Meanwhile, piezoceramic sensors mounted on the pipeline convert the stress waves to electric signals and the signal can be demodulated. In order to enable the encoding and decoding of information in the stress wave, a PPM-based communication protocol was integrated into the software system. A verification experiment demonstrates the functionality of the developed system for stress wave communication using piezoceramic transducers and the result shows that the data transmission speed of this new communication system can reach 67 bits per second (bps).
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.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.