A Data-Driven Approach For Monitoring And Predictive Diagnosis Of Sucker Rod Pump System

Given its long operational history, a sucker-rod pump (SRP) has been widely utilized as a lifting solution to bring reservoir fluids to the surface with low cost and high efficiency. However, debugging the rod pump issues requires on-site activities that could cost time and money for operators. With the vast dataset collected from years of operation, numerous companies are looking to turn these engineering processes into automated systems in the oilfield network, despite the complexity of data and lack of knowledge. The integral approach is to develop real-time diagnostics for downhole conditions. The emerging artificial intelligence and big-data analytics have provided relatively precise downhole condition forecasting based on available data, enabling better decision-making. This thesis focuses on collecting representative data and utilizing machine learning techniques to predict operational anomalies of sucker-rod pumps. An experimental design at the University of Oklahoma, referred to as Interactive Digital Sucker Rod Pumping Unit (IDSRP), was used to facilitate a data-driven solution and monitor SRP performance and diagnostics. The physical framework includes a 50-ft transparent casing and tubing with a downhole rod pump at the bottom. A linear actuator provides the rod string’s reciprocal movement and simulates different surface units and operating scenarios. This facility uses proper instrumentation and a data acquisition system for signal sensor readings. A workflow is developed to translate surface dynamometer cards to downhole ones and train predictive models in time-driven pressure and rate data. Though primarily focusing on the normal pump operation, the test matrix varies in stroke length, pump speed, and rod movement shape. The tests validate the model to classify and detect various operational conditions in sucker-rod pumps. The model dynamically categorizes the pumps into key states of ideal condition and over-pumping with a regression fit of accuracy higher than 0.7 and overall classification accuracy of 92%. Moreover, the real-time model anticipates an event in which the pump experiences a slight pumping-off that could potentially deteriorate the rod. The results also help understand key features that drive sucker rod pump performance prediction and help detect anomalous pump behavior. The machine learning algorithms, developed by the physics-based inputs, generate predictive models, thus classifying operational conditions or failures of the pump. The diagnosis for the pump’s anomalies is also predicted by a real time analysis. The visualization enables to recognize the patterns and abnormal phases early. The explainable machine learning (i.e. Shapley additive explanation) helps decoding the predictive models with feature importance, local and global sensitivities in categorizing SRP conditions. The developed unit has the capability of working with different well conditions, combining with real-time training and applying models, to initiate early warnings. The developed processes and workflows have the potential of becoming a generic optimizing and monitoring model for rod pumps. The novelty of this setup consists not only in its mechatronic design but also in through monitoring of the pump operations

Uniform Corrosion and Its Effect on Tubing Simulation Study

Master's thesis in Petroleum engineeringThe API Barlow and the Tri-axial equations cannot be applied to predict burst pressure in the case of pitting corrosion. The main reason for this is that these models are derived from continuum mechanics, but fracture mechanics is more relevant to pitting corrosion damage. However, up to this level of research, the author was unable to find any analytical documented model used to predict de-rating loading in pitting damage. The simulation results show that the API models can only be applied in the case of uniform corrosion. In pitting corrosion, a FEM-based model presents a more trustworthy prediction of burst and collapse. Based on the findings of this research, the author believes that FEM modeling is very reliable for any types of damage

INVESTIGATION OF CASING DEFORMATION DURING HYDRAULIC FRACTURING CONSIDERING WELLBORE CENTRALIZATION AND CEMENT VOIDS

The fast growth of shale gas development through horizontal drilling and hydraulic fracturing has expanded the extraction of hydrocarbon resources in countries such as the United States, China, and Argentina. Even though the technology of fracturing low permeable shale can be replicated in different reservoirs, factors such as flow regime, high horizontal stress anisotropy, formation temperature and quantity of natural fractures will dictate several changes and considerations in the completion design. High rates and pressures applied during hydraulic fracturing in a long horizontal section could induce wellbore integrity issues. This work will focus on researching how the integrity of the cement and casing is affected during these operations. A finite element analysis (FEA) was performed in order to study the stress concentration in casing and cement. The yield criterion of equivalent von Mises stress was applied in order to verify if the stresses were exceeding the casing yield strength and the cement compressive strength. The majority of the input parameters were based on a real case of casing deformation during hydraulic fracturing in a shale gas play in China. The effect of wellbore centralization in wellbore integrity was the main parameter modeled in this work. It was demonstrated that a poor centralization that contributes to the formation of drilling fluid voids in the cement will induce casing failure during hydraulic fracturing operations. The equivalent maximum stress can increase from three to four times in casing and cement from a concentric case to an eccentric case in a cement sheath with voids. Boundary conditions were also studied in order to evaluate if the stress impact on the casing and cement are different and significant

Feasibility Study on the Reduction of Hydrostatic Pressure in a Deep-Water Riser Using a Gas-Lift Method.

Recent successful exploration efforts in deep waters have heightened interest in developing oil and gas reservoirs on the continental slope. Leases have been obtained in water depths up to 10,000 ft with a requirement that they be drilled within the next decade. Use of current techniques to drill these leases will require extremely large floating drilling units and large diameter marine riser systems. This study presents the results of a feasibility study on the use of an automated gas-lift system for a marine riser that will maintain the hydrostatic pressure in the subsea well-head equal to that of the sea water at the sea floor. Hydrostatic control of abnormal formation pressure could still be maintained by a weighted mud system that is not gas-cut below the sea floor. Such a dual density mud system could reduce drilling costs by reducing the number of casing strings required to drill the well and so reducing the time required to drill a deep-water well. The system would have the advantages of riserless drilling without giving up the well control advantages of a closed, weighted mud system. A steady-state numerical model was developed that can be used to determine the gas injection requirements needed to achieve a desired dual density configuration. The numerical model was verified through tests conducted in a 6,000 foot research well. Once verified, the model was used to define the gas requirements and practical limits of a marine gas-lift system based on estimated additional costs of gas compression and nitrogen membrane filters. The practical limits are presented in terms of maximum mud density, water depth, and riser diameter combinations. The dissertation also discusses the operational changes that would be required for various drilling procedures such as making a connection, running casing, kick detection, and well control operations

Kinematics and Robot Design I, KaRD2018

This volume collects the papers published on the Special Issue “Kinematics and Robot Design I, KaRD2018” (https://www.mdpi.com/journal/robotics/special_issues/KARD), which is the first issue of the KaRD Special Issue series, hosted by the open access journal “MDPI Robotics”. The KaRD series aims at creating an open environment where researchers can present their works and discuss all the topics focused on the many aspects that involve kinematics in the design of robotic/automatic systems. Kinematics is so intimately related to the design of robotic/automatic systems that the admitted topics of the KaRD series practically cover all the subjects normally present in well-established international conferences on “mechanisms and robotics”. KaRD2018 received 22 papers and, after the peer-review process, accepted only 14 papers. The accepted papers cover some theoretical and many design/applicative aspects

A History of Materials and Technologies Development

The purpose of the book is to provide the students with the text that presents an introductory knowledge about the development of materials and technologies and includes the most commonly available information on human development. The idea of the publication has been generated referring to the materials taken from the organic and non-organic evolution of nature. The suggested texts might be found a purposeful tool for the University students proceeding with studying engineering due to the fact that all subjects in this particular field more or less have to cover the history and development of the studied object. It is expected that studying different materials and technologies will help the students with a better understanding of driving forces, positive and negative consequences of technological development, etc

EXPERIMENTAL STUDIES FOR DEVELOPMENT HIGH-POWER AUDIO SPEAKER DEVICES PERFORMANCE USING PERMANENT NdFeB MAGNETS SPECIAL TECHNOLOGY

In this paper the authors shows the research made for improving high-power audio speaker devices performance using permanent NdFeB magnets special technology. Magnetic losses inside these audio devices are due to mechanical system frictions and to thermal effect of Joules eddy currents. In this regard, by special technology, were made conical surfaces at top plate and center pin. Analysing results obtained by modelling the magnetic circuit finite element method using electronic software package,was measured increase efficiency by over 10 %, from 1,136T to13T

Maritime expressions:a corpus based exploration of maritime metaphors

This study uses a purpose-built corpus to explore the linguistic legacy of Britain’s maritime history found in the form of hundreds of specialised ‘Maritime Expressions’ (MEs), such as TAKEN ABACK, ANCHOR and ALOOF, that permeate modern English. Selecting just those expressions commencing with ’A’, it analyses 61 MEs in detail and describes the processes by which these technical expressions, from a highly specialised occupational discourse community, have made their way into modern English. The Maritime Text Corpus (MTC) comprises 8.8 million words, encompassing a range of text types and registers, selected to provide a cross-section of ‘maritime’ writing. It is analysed using WordSmith analytical software (Scott, 2010), with the 100 million-word British National Corpus (BNC) as a reference corpus. Using the MTC, a list of keywords of specific salience within the maritime discourse has been compiled and, using frequency data, concordances and collocations, these MEs are described in detail and their use and form in the MTC and the BNC is compared. The study examines the transformation from ME to figurative use in the general discourse, in terms of form and metaphoricity. MEs are classified according to their metaphorical strength and their transference from maritime usage into new registers and domains such as those of business, politics, sports and reportage etc. A revised model of metaphoricity is developed and a new category of figurative expression, the ‘resonator’, is proposed. Additionally, developing the work of Lakov and Johnson, Kovesces and others on Conceptual Metaphor Theory (CMT), a number of Maritime Conceptual Metaphors are identified and their cultural significance is discussed