Design of Steel Lazy Wave Riser for External Turret Moored FPSO

2019 ◽  
Author(s):  
Jingyun Cheng ◽  
Peimin Cao
Keyword(s):  
Water Depth ◽  
Optimal Solution ◽  
Cost Effective ◽  
Fatigue Performance ◽  
Effective Solution ◽  
Field Development ◽  
Riser Design ◽  
Preferred Solutions ◽  
Design Challenges ◽  
Selection Of

Abstract The external turret moored Floating Production Storage and Offloading system (FPSO) is one of the preferred solutions for deepwater fields in mild to moderate environments and far away from existing pipeline infrastructures. This paper presents a design of steel lazy wave riser (SLWR) system for an external turret moored FPSO in the water depth of 1,500 meter. The design challenges and feasibility are discussed. Due to the complexity of SLWR geometry, a systematic configuration approach is introduced to achieve the desired riser extreme and fatigue performance target, as well as external turret layout. The study includes the standardized FPSO, the selection of turret configuration, and riser design. The titanium taper stress joints and the interaction with turret structure are also studied. The study provides an optimal solution of the integrated turret, mooring and riser system. It concludes that external turret FPSO with SLWRs can be a feasible and cost effective solution for field development in mild to moderate environments.

Steel Lazy Wave Riser Design for Semi-Submersible in Harsh Environment

2014 ◽  
Author(s):  
Jingyun Cheng ◽  
Peimin Cao
Keyword(s):  
Water Depth ◽  
Optimal Solution ◽  
Cost Effective ◽  
Harsh Environment ◽  
Depth Range ◽  
Strength Performance ◽  
Field Development ◽  
Steel Catenary Risers ◽  
Riser Design ◽  
Design Guidance

Deep draft production semi-submersible with steel lazy wave risers (SLWRs) has been studied for the 2,625ft water depth in harsh environment. The design challenges and feasibility of steel catenary risers (SCRs) for semi-submersible at relatively shallow water and harsh environment are discussed. The benefits of using SLWRs to improve riser strength and fatigue performance are presented. Due to the complexity of SLWR geometry, a systematic configuration approach is introduced to achieve the desired riser performance target. A comparison study on fatigue and strength performance of various riser configurations is performed. The assessment provides design guidance for the optimal solution of the integrated hull, mooring and riser system. It concludes that deep draft production semi-submersible with SLWRs can be a feasible and cost effective solution for field development at water depth range from 2,297ft to 3,281ft in harsh environment.

Wet Tree Semi-Submersible With SCRs for 4,000 ft Water Depth in the Gulf of Mexico

2011 ◽  
Author(s):  
Jingyun Cheng ◽  
Peimin Cao ◽  
Sherry Xiang
Keyword(s):  
Gulf Of Mexico ◽  
Water Depth ◽  
Cost Effective ◽  
Integrated System ◽  
Fatigue Performance ◽  
Strength Performance ◽  
Field Development ◽  
Vessel Motion ◽  
Optimum Solution ◽  
Mitigation Methods

This paper presents a design of a deep draft wet tree semi-submersible with steel catenary risers (SCRs) for 4,000 ft water depth in the Gulf of Mexico (GoM). The integrated system of hull, mooring, and SCRs is discussed. The design challenges of SCRs are highlighted and results of SCR strength and fatigue performance are presented. A comparison study on strength performance of various types of risers under the GoM environment criteria is performed. The assessment of extreme strength responses from various riser and hull configurations provide guidelines for the best hull selection. Sour service requirement creates challenges in the fatigue design of the production riser system at such water depth. Integrated mooring and riser design provides an optimum solution. It’s found that the majority of riser fatigue damage at touch down zone is generated by wave loading & resultant vessel motion and vortex induced vessel motion (VIM). Several fatigue mitigation methods are suggested to improve the riser fatigue performance, such as planned vessel repositioning. The conclusion of this study is that deep draft wet tree semi-submersible with SCRs can be a cost effective solution for field development at 4,000 ft water depth in the Gulf of Mexico.

Design of Steel Lazy Wave Riser for Disconnectable FPSO in the Gulf of Mexico

2013 ◽  
Author(s):  
Jingyun Cheng ◽  
Peimin Cao
Keyword(s):  
Gulf Of Mexico ◽  
Water Injection ◽  
Integrated Design ◽  
Cost Effective ◽  
Performance Criteria ◽  
Harsh Environment ◽  
Effective Solution ◽  
Field Development ◽  
Integrated Design Approach ◽  
Preferred Solutions

The disconnectable Floating Production Storage and Offloading system (FPSO) is one of the preferred solutions for the deepwater field in the harsh environment and far away from existing pipeline infrastructures. This paper presents a design of steel lazy wave riser (SLWR) system for an internal turret moored disconnectable FPSO in the Gulf of Mexico. The integrated systems of FPSO, disconnectable buoy, riser, and mooring are discussed while focusing on the design challenges of SLWR system. Due to the complexity of SLWR geometry, a systematic configuration approach is introduced based on buoy payload and riser performance criteria. The study includes the strength and fatigue analysis of production, gas export and water injection risers for the connected, disconnecting, and disconnected conditions. The sensitivity of buoy disconnecting due to vessel offset is also presented. It concludes that SLWR with disconnectable FPSO is a feasible and cost effective solution for deepwater field development in the Gulf of Mexico. The study demonstrates the importance of an integrated design approach, and provides guidance for configuring and design of future disconnectable systems with SLWRs.

Hydrodynamic Properties of an Asymmetric Deepwater Riser Bundle

2006 ◽  
Author(s):  
Charles Zimmermann ◽  
Richard James ◽  
Blaise Seguin ◽  
Mattias Lynch
Keyword(s):  
Cross Section ◽  
Water Depth ◽  
Hydrodynamic Characteristics ◽  
Cfd Analysis ◽  
Effective Solution ◽  
Hydrodynamic Properties ◽  
Global System ◽  
Field Development ◽  
Hydrodynamic Behaviour ◽  
Deepwater Riser

The BP operated Greater Plutonio field development offshore Angola comprises a spread-moored FPSO in 1,300 m water depth, serving as a hub processing the fluids produced from or injected into the subsea wells. The selected riser system is a riser tower tensioned by a steel buoyancy tank at its top end and distributed foam buoyancy along a central structural tubular. The riser bundle is asymmetric in cross-section and this paper presents the work performed to determine the specific hydrodynamic characteristics of the design. Both basin tests and CFD analysis results are presented with discussion on some specific hydrodynamic issues: vortex-induced vibration (VIV) of the global riser tower system, VIV of individual risers, and the dynamic stability of the global system (i.e. galloping). Finally, guidelines for the assessment of the hydrodynamic behaviour of such system geometries are proposed. The results of this paper demonstrate that the Greater Plutonio riser bundle represents an effective solution in term of hydrodynamic behaviour and is not sensitive to VIV fatigue or galloping.

Three-Column TLP Concept for Marginal Field Development

2009 ◽  
Author(s):  
Neil Williams ◽  
Homayoun Heidari ◽  
Sean Large
Keyword(s):  
Equilateral Triangle ◽  
Cost Effective ◽  
Technical Development ◽  
Effective Solution ◽  
Field Development ◽  
Geometric Center ◽  
Marginal Field ◽  
Rectangular Columns

This paper discusses the development of a new self-stable TLP concept for marginal field applications. This concept — called ThreeStar™ — is based on three rectangular columns arranged at the vertices of an equilateral triangle and battered towards its geometric center. The columns are joined by conventional rectangular pontoons. The reduced number of tendons/piles relative to a conventional four column TLP makes the ThreeStar a cost-effective solution in applications where the production riser count is relatively low or the topsides payload is small. This paper presents a description of the technical development of the ThreeStar TLP and outlines the unique features of the concept. The relative merits of the ThreeStar over comparable four-column TLPs for different environments and payload ranges are discussed. Finally, ThreeStar systems are presented for two example deepwater applications.

scholarly journals Process Plant Upgradation Using Reliability, Availability, and Maintainability (RAM) Criteria

2022 ◽  
Vol 2022 ◽  
pp. 1-17
Author(s):  
Dongqiao Bai ◽  
Qi Yang ◽  
Jian Zhang ◽  
Shouzhi Li
Keyword(s):  
Modular Design ◽  
Cost Effective ◽  
Market Survey ◽  
Effective Solution ◽  
Process Plant ◽  
Process Plants ◽  
Reliability And Availability ◽  
Expected Outcomes ◽  
Selection Of

The objective of this study is to propose a solution for process plant upgradation becoming extinct due to obsoleteness of spares. The study will help in reliability, availability, and maintainability (RAM) based upgradation of control system of process plants in developing countries. Available options for plant upgradation are compact control, modular, and semiautomatic. RAM based upgradation provides solution which is high in reliability and availability (usually all parts are replaced with upgraded and compatible technology) and is easy to maintain throughout the service life of process plant. Case study for stacker and reclaimer of cement plant upgradation is considered to both implement and evaluate the idea. Upgradation methodology is finalized by expert’s feedback regarding selection of hardware with respect to availability, market survey to validate the opinion, and economical availability viability of selected hardware. Pre- and postupgradation scenarios are analyzed to validate the implementation of study and conclude the expected outcomes. The process plant upgradation yielded a cost-effective solution to the problem with automation increasing by 17%, plant maintainability increasing by 80%, and downtime of plant decreasing by 17%. Among all available options, modular design Op1 is considered the best choice that can satisfy RAM criteria.

Deep Draft Semi Submersible

2002 ◽  
Author(s):  
Arne Ulrik Bindingsbo̸ ◽  
Arve Bjo̸rset
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Water Depth ◽  
Flexible Riser ◽  
Production Platform ◽  
Steel Catenary Risers ◽  
Riser Design ◽  
Flexible Risers ◽  
Gas Fields ◽  
Preferred Solutions

High Pressure and High Temperature wells together with harsh environmental conditions puts a tough challenge on the flowline and riser design. The flexible riser which has been the favorite choice for many field developments with subsea wells have several technical limitations. Large gas fields such as Ormen Lange require large bore export risers. Steel risers are the preferred solutions with respect to durability and cost. Unfortunately, it is difficult for steel risers to accommodate the vessel motions of a semi submersible or ship. Heave restricted vessels such as TLP or SPAR are used together with toptensioned risers and surface trees. Based on the limitations of flexible risers Hydro is pursuing extensive research on riser and floater technology. As part of this research program a study on the effect on riser design caused by reducing vessel motions. The main goal is to introduce steel catenary risers (SCR) on semi submersible platforms. The typical draft of a semi submersible production platform is 20–25 m. By reengineering the design of such a platform and increasing the draft from 21 m to 40 m the vessel motions were reduced significantly. Hence, an opening for novel riser solutions was made. ULS and FLS analyses for 10″ and 30″ SCR in 300 and 1000 m water depth were carried out. The key result is that the 10Prime; riser satisfies both the ULS and FLS requirement for both vessel drafts and water depth and the 30Prime; riser satisfies the both the ULS and FLS requirement for the 40 m vessel draft at 1000 m water depth.

Flowline Bundle Concept for JZ 9-3 Field Development

2014 ◽  
Author(s):  
Jing Cao ◽  
Yong Sha ◽  
Liwei Li
Keyword(s):  
Engineering Design ◽  
Corrosion Protection ◽  
Thermal Performance ◽  
Oil And Gas ◽  
Cost Effective ◽  
Development Project ◽  
Bohai Bay ◽  
Effective Solution ◽  
Field Development ◽  
Protection Potential

Flowline bundle system consisting of carrier pipe, sleeve pipe and internal flowlines offers smart solution for the infield transportation of oil and gas. Due to its features, flowline bundle offers a couple of advantages over conventional flowline in particular for cases where multi-flowlines and high thermal performance are of great interests. The main benefits and advantages of such system include excellent thermal performance to prevent wax formation and hydrates, multiple bundled flowlines, mechanical and corrosion protection, potential reuse, fabricated onshore, as well as towing installation without the requirement of professional pipelay vessel etc. Flowline bundle system can be a smart solution for certain applications, which can be safe and cost effective solution. The objective of this paper is to present the feasibility study of flowline bundle concept for the JZ 9-3 West Development project in Bohai Bay, Offshore China. This study covers engineering design, fabrication, and offshore towing installation. Design and installation results have been presented and the feasibility of flowline bundle concept has been fully demonstrated for the JZ 9-3 West field development.

Effect of Polyester Mooring Stiffness on SCR Design for FPSO Application

2012 ◽  
Author(s):  
Gwo-Ang Chang ◽  
Pao-Lin Tan ◽  
Ken Huang ◽  
Tom Kwan
Keyword(s):  
Global Analysis ◽  
Dynamic Stiffness ◽  
Cost Effective ◽  
Systematic Investigation ◽  
Steel Catenary Riser ◽  
Motion Responses ◽  
Stiffness Model ◽  
Riser Design ◽  
The Impact ◽  
Selection Of

Polyester rope is a visco-elastic material and its stiffness is affected by mean tension, tension amplitude, loading period, and loading history. Qualitatively it may be felt that rope stiffness significantly affects vessel offset, which in turn affects riser performance and cost. However, a systematic investigation of the impact of rope stiffness on riser stress and fatigue life has not been published for a wide variety of design conditions. This paper describes such a study, and provides specific guidance to designers for the prudent selection of a rope stiffness model and values to achieve safe and cost effective riser design. This study investigated the effect of polyester rope stiffness on steel catenary riser (SCR) design for an FPSO sited in a variety of water depths considering environmental conditions representative of West Africa. Static/dynamic stiffness models for polyester rope in the recently issued ABS Guidance Notes on the Application of Fiber Rope for Offshore Mooring [1] were used in a global analysis to provide motion responses for the riser analysis. Time domain riser analysis was performed to obtain maximum riser stress and fatigue damage under various conditions. Based on the results of the investigation of riser and mooring analysis, guidance on the impact of rope stiffness to the riser design has been developed.

Optimization of Catenary Risers

1999 ◽  
Vol 121 (2) ◽  
pp. 90-94 ◽  
Author(s):  
C. M. Larsen ◽  
T. Hanson
Keyword(s):  
Water Depth ◽  
Equivalent Stress ◽  
Nonlinear Function ◽  
Design Parameters ◽  
Design Variables ◽  
Function Design ◽  
General Constraints ◽  
Riser Design ◽  
Selection Of

This paper describes how the design of a catenary riser can be formulated as an optimization problem by using riser costs as the criteria function, design requirements in terms of maximum allowable stress and buckling capacity as constraints, and riser dimensions as free variables. The theory has been implemented in a computer program that can generate an optimized riser design for given design parameters such as water depth, diameter, pressure, and platform excursions. The developed software consists of a conventional program for two-dimensional riser analysis and a set of standard routines to minimize a nonlinear function subjected to general constraints. A case study where design parameters and requirements have been varied is also presented. The importance of buckling versus allowable equivalent stress as the most critical constraint has been investigated for varying water depth. The Conclusion of this work is that optimization is a useful tool for riser design, and that the proposed strategy for selection of design variables and constraints will enable an engineer to identify designs with minimum costs in an efficient way.

Sign in / Sign up

Export Citation Format

Share Document