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When Subsea equipment (MEG Filter and Back Pressure Regulator) is damaged, the overall system is need to retrieved and taken to the offshore rig platform for replacement of Subsea equipment. This process usually takes 72-96 hours. During the removal of Subsea equipment, the process is disrupted and removal of subsea equipment using conventional retrieval tools is difficult due to absence of lifting arrangements and the tools may damage. Moreover, the process is need to stopped during retrieval. To get the better of these difficulties and reduce the breakdown time of production, a special Subsea Skid for Component Deployment frame is designed. The SSCD frame carries the Subsea components like Back pressure regulator and MEG Filter from Offshore rig to the Sea bed where the production process is going on. The main aim of this study is to analyze the SSCD frame for structural stability under various loading conditions. The time required to replace the damaged component with new component is 3 to 4 hours by this SSCD frame. The components are manipulated with the help of Remote Operated Vehicles (ROVs). Thus, with the help of this frame the components can be safely deployed to the production system with minimum time, cost & damage. [ABSTRACT FROM AUTHOR]

Technical integrity of a full scale test facility for compressors, separators, valves, flow meters, etc. is a key factor in achieving on plan and budget project development safely. The methodology for successful technical integrity of such a test facility, compared to the technical integrity of a process plant, is outlined. This implies, coordination between technical disciplines and highly qualified personnel and also custom Life Cycle Information (LCI) strategy. When such large scale test facility is integrated in a process plant the technical requirements are even stricter and need to comply both with offshore requirements and onshore process plant requirements. The novelty of the tested technologies, and sometimes the lack of appropriate mature standards, makes it challenging to ensure safe technical integrity solutions for such test facilities. Continuously changing projects, and short time commissioning and decommissioning of equipment, increases the complexity of the test facility and the associated risks. Sound risk assessments, quantitative as well as qualitative assessments, are performed for understanding the integrity limits and their risk contribution. Realistic offshore conditions are the driver to develop innovative cost effective approaches to full scale testing. Examples of such tests are outlined herein, i.e. testing of a submerged 11 MW subsea compressor module weighing 350 metric tons, meant to work on the subsea bed. [ABSTRACT FROM AUTHOR]

The paper focuses on a part of a large feasibility study conducted for Statoil ASA. The target of the study was a method for hyperbaric drying of a subsea welding chamber used in maintenance and repair operations of subsea pipelines. In order to verify the consistency of the numerical representation of convection and temperature distribution a welding chamber prototype was built and tested in atmospheric conditions. In this work we investigated conditions for heating and drying of the welding chamber prototype using methods of Computational Fluid Dynamics (CFD). Simulated convection patterns and temperature distributions are compared with the real world experiment performed by Statoil. The main goal of our research was to confirm that CFD can represent the real world phenomena and thus can conservatively be used for further investigations of the welding chamber. [ABSTRACT FROM AUTHOR]

This paper investigates whether using protection covers made of reinforced concrete is a viable alternative to glass-reinforced plastic (GRP) for protection of subsea equipment installed on the seabed. This is done by performing dropped object impact tests and analyses on the concrete protection cover. The theory behind this paper is that the higher density and the thicker walls of the concrete covers will ensure that the structures are heavy enough to be stable on the seabed without added ballast weight and rock dumping, which often is necessary for GRP covers. The type of protection cover assessed is a conventional tunnel cover, which is typically used to cover pipelines or spools. A 3D model of the reinforced concrete cover was created, and dynamic finite clement analyses of the impact tests were performed using the software Ansys® Workbench, Release 14,5. Design loads and impact energies used in the tests are given in NORSOK standard U-001, Rev. 3. Full scale dropped object impact tests of the impact energy requirements were performed on the reinforced concrete covers. The tests were performed with the covers submerged in the test basin in the laboratories at the University of Stavanger. The concrete covers cracked and deformed slightly, but none were penetrated or collapsed. The dropped object tests proved that the strength of the concrete protection covers was sufficient to withstand the dropped object impact energies, and that the initial design of the cover is suitable for further enhancement. Its heavy weight, high strength and the possible avoidance of rock dump requirements gives the concrete protection cover a competitive edge that is well worth exploring further. [ABSTRACT FROM AUTHOR]

The article discusses research which examined the installation of infield umbilical that provides control to remote wells or tie-ins of subsea developments, with compliant umbilical termination heads (UTH). Topics discussed include a description of the PY 35-2/35-1 infield umbilical system, infield umbilical installation concerns and UTH handling test.

The article discusses research which examined the design and installation of PY35-2/35-1 jumper in South China Sea with corrosion resistance alloy (CRA) liner. Topics discussed include the design parameters of the jumpers, constructability of jumpers in both technical and commercial areas and jumper configuration and lifting analysis.

The article discusses research which investigated the carbon dioxide subsea releases underwater. Topics discussed include the risk on offshore infrastructures, ships and the marine environment by offshore carbon dioxide pipelines, an overview of the carbon dioxide transportation by pipeline and design of the release pipework.

This article discusses research which examined the geotechnical aspects of the offshore decommissioning in the North Sea to highlight the challenges and importance of geotechnical conditions during the engineering phase of the project. Topics discussed include current decommissioning practice of various types of subsea structures, moorings and pipelines/cables and potential solutions for recovery of subsea structures using smaller vessels.

The article discusses a study on the structural design and analysis of the shell of a subsea camera, which is used in offshore engineering. Topics addressed include the shell structure's design and analysis with the Design By Analysis (DBA) method for its high external pressure, the use of the finite element method for analyzing plastic collapse and buckling collapse, and allowable pressure loads. Subsea cameras' role in offshore oil exploration is also mentioned.

Long-distance Power-Data Hybrid Transmission System provides long-term easy, safe, and reliable power supply and data transmission method for the observation and sampling of deep sea. A hybrid transmission system based on G.SHDSL has been designed and the hybrid transmission of electric energy, subsea video and the data of surface and underwater unit on one coaxial armored cable has been realized in our past researches, and it can be applied to supply the power for the control system that including television grab bucket, deep sea drilling, integrated towed vehicle, visual multi-barrel sampler. For increasingly vaster underwater investigation, ground fault detection and water leakage detection module based on original system have been designed in this paper to provide safer and more comprehensive power supply for underwater application. [ABSTRACT FROM PUBLISHER]

The article presents a study which developed dimensional modeling of lower offshore rig components and simulator of drilling processes for the offshore rig. The three-dimensional (3-D) model information model and scenarios were used to develop the simulator. The simulator reportedly shows similar operation as the drilling process. The simulator can be used in education to make the students and industry engineers understand and improve the drilling technology.

The article discusses a study to determine the benefits of using a shallow water pig launcher/receiver when developing a deep water field in remote areas where a large deep water pipelay vessel is cost prohibitive to mobilize. The two types of pig launchers/receivers presently used in the industry are described. The design challenges and regular pigging methodologies for each type are discussed.

In this paper we describe the measurement and simulation based validation of a theoretical model for the insulated wire antenna immersed in saltwater. Good agreement to VHF frequencies was observed between the theoretical, simulated and measured results for the travelling wave current on the insulated wire. In addition, comparison of the magnetic field calculated using this current with full wave simulated fields showed good agreement at various positions in the water around the wire. [ABSTRACT FROM PUBLISHER]

The variation of through-water electromagnetic wave propagation parameters with frequency and conductivity is discussed together with wideband signal distortion caused by dispersion. Environmental electromagnetic noise and its limitation on the underwater communication range of various antennas are examined. Submarine communication and heuristic models of antenna types are presented, together with supporting experimental validation, and practical comment is made on potential range and bandwidth capabilities of generic antenna systems, and on current directions of research and development, including high frequency and dual mode subsea communications. [ABSTRACT FROM PUBLISHER]

The article discusses a study that examined a simplified approach to establish the limiting sea-states and dynamic loads for deepwater lifting. According to the article, detailed planning is needed in order to establish cost-effective and safe operational procedures for a deep water installation. Accurate time-domain analyses in cases where the basic assumptions are not fulfilled are recommended.

The article reports on a study concerning the changes made to the design of the Subsea Dynamic Riser Base (SDRB) of the HYSY111 floating production storage and offloading (FPSO) system. Topics discussed include corrosion as the main reason behind the design improvements, the factors considered in planning the replacement for the SDRB and the significance of the design details for similar subsea products used in the South China Sea.