Structural and Hydrodynamic Aspects of Steel Lazy Wave Riser in Deepwater

2019 ◽  
Vol 142 (2) ◽  
Author(s):  
Decao Yin ◽  
Halvor Lie ◽  
Jie Wu
Keyword(s):  
Oil And Gas ◽  
Weather Condition ◽  
Cost Effective ◽  
Dynamic Responses ◽  
Oil Flow ◽  
Flow Induced Vibrations ◽  
Cost Effective Alternative ◽  
Complex Structural ◽  
Structural Configurations ◽  
Arch Shape

Abstract Exploration of oil and gas in deep and ultra-deepwater under harsh weather condition is challenging. A steel lazy wave riser (SLWR) is considered to be a cost-effective alternative to get the gas or oil flow up to the platform under these conditions. The staggered buoyant section provides buoyancy force which forms an arch shape of the SLWR. This arch shape makes the SLWR configuration flexible and isolates the dynamic responses of the upper part and lower part of the riser. However, there is a lack of full understanding of the behavior of SLWRs. This is, due to a complicated loading from waves, vessel motions and flow induced vibrations caused by ocean currents, complex structural configurations, and non-linearities. Time-domain simulation is necessary to accurately predict the dynamic responses and capture the non-linearities. Realistic fatigue damage calculation is essential in the design phase of SLWR. The design of SLWR could be optimized with a better understanding of the dynamic responses of SLWR.

Lazy-Wave Steel Rigid Risers for Turret-Moored FPSO

2002 ◽  
Author(s):  
Ana Lu´cia F. Lima Torres ◽  
Enrique Casaprima Gonzalez ◽  
Marcos Queija de Siqueira ◽  
Claudio Marcio Silva Dantas ◽  
Marcio Martins Mourelle ◽  
...  
Keyword(s):  
Structural Integrity ◽  
Oil And Gas ◽  
Large Diameter ◽  
Cost Effective ◽  
Steel Catenary Riser ◽  
Deep Waters ◽  
Exploration And Production ◽  
Vibration Fatigue ◽  
Cost Effective Alternative ◽  
Available Technology

The free-hanging SCR (Steel Catenary Riser) was adopted by Petrobras as a cost-effective alternative for oil and gas export lines on deepwater fields, where large diameter flexible risers present technical and economic limitations. It is considered an available technology for semi-submersible application. There was interest in applying SCR’s attached to FPSO (Floating, Production, Storage and Offloading) units due to the trend of using these units for exploration and production in Brazilian deep waters. This alternative has to be carefully studied due to the high offsets and heave motions imposed by the vessel on the top of the riser. This work presents the approach and methodology adopted in Petrobras to study the structural integrity and feasibility of a lazy-wave SCR attached to a bow turret-moored FPSO at a water depth of 1290 m. The analysis was performed using the Petrobras’s in-house computer codes ANFLEX and POSFAL developed and implemented as part of projects from CENPES with “COPPE/UFRJ - The Engineering Post-Graduating Coordination of the Federal University of Rio de Janeiro”. For VIV (Vortex Induced Vibration) fatigue damage calculation SHEAR7 was used.

2D Color-Intensity Representation of Ultrasonic Thickness Gauge Measurements

2020 ◽  
pp. 1192-1198
Author(s):  
M.S. Mohammad ◽  
Tibebe Tesfaye ◽  
Kim Ki-Seong
Keyword(s):  
Cost Effective ◽  
The Other ◽  
Thickness Gauge ◽  
Color Intensity ◽  
Digital Readout ◽  
Flat Surfaces ◽  
Video Cameras ◽  
Wide Range ◽  
Cost Effective Alternative ◽  
Ultrasonic Thickness

Ultrasonic thickness gauges are easy to operate and reliable, and can be used to measure a wide range of thicknesses and inspect all engineering materials. Supplementing the simple ultrasonic thickness gauges that present results in either a digital readout or as an A-scan with systems that enable correlating the measured values to their positions on the inspected surface to produce a two-dimensional (2D) thickness representation can extend their benefits and provide a cost-effective alternative to expensive advanced C-scan machines. In previous work, the authors introduced a system for the positioning and mapping of the values measured by the ultrasonic thickness gauges and flaw detectors (Tesfaye et al. 2019). The system is an alternative to the systems that use mechanical scanners, encoders, and sophisticated UT machines. It used a camera to record the probe’s movement and a projected laser grid obtained by a laser pattern generator to locate the probe on the inspected surface. In this paper, a novel system is proposed to be applied to flat surfaces, in addition to overcoming the other limitations posed due to the use of the laser projection. The proposed system uses two video cameras, one to monitor the probe’s movement on the inspected surface and the other to capture the corresponding digital readout of the thickness gauge. The acquired images of the probe’s position and thickness gauge readout are processed to plot the measured data in a 2D color-coded map. The system is meant to be simpler and more effective than the previous development.

Sand Free Production Success Through Proven Technology Enabler from An Untapped Heterogeneous Reservoir Zone Utilizing Gravel Pack Replacement Methodology

2020 ◽  
Author(s):  
Y. Anggoro
Keyword(s):  
Oil And Gas ◽  
Erosion Resistance ◽  
Cost Effective ◽  
High Rate ◽  
Screen Design ◽  
Sand Control ◽  
Rules Of Thumb ◽  
Production Success ◽  
Control Technologies ◽  
Gravel Pack

The Belida field is an offshore field located in Block B of Indonesia’s South Natuna Sea. This field was discovered in 1989. Both oil and gas bearing reservoirs are present in the Belida field in the Miocene Arang, Udang and Intra Barat Formations. Within the middle Arang Formation, there are three gas pay zones informally referred to as Beta, Gamma and Delta. These sand zones are thin pay zones which need to be carefully planned and economically exploited. Due to the nature of the reservoir, sand production is a challenge and requires downhole sand control. A key challenge for sand control equipment in this application is erosion resistance without inhibiting productivity as high gas rates and associated high flow velocity is expected from the zones, which is known to have caused sand control failure. To help achieve a cost-effective and easily planned deployment solution to produce hydrocarbons, a rigless deployment is the preferred method to deploy downhole sand control. PSD analysis from the reservoir zone suggested from ‘Industry Rules of Thumb’ a conventional gravel pack deployment as a means of downhole sand control. However, based on review of newer globally proven sand control technologies since adoption of these ‘Industry Rules of Thumb’, a cost-effective solution could be considered and implemented utilizing Ceramic Sand Screen technology. This paper will discuss the successful application at Block B, Natuna Sea using Ceramic Sand Screens as a rigless intervention solution addressing the erosion / hot spotting challenges in these high rate production zones. The erosion resistance of the Ceramic Sand Screen design allows a deployment methodology directly adjacent to the perforated interval to resist against premature loss of sand control. The robust ceramic screen design gave the flexibility required to develop a cost-effective lower completion deployment methodology both from a challenging make up in the well due to a restrictive lubricator length to the tractor conveyancing in the well to land out at the desired set depth covering the producing zone. The paper will overview the success of multi-service and product supply co-operation adopting technology enablers to challenge ‘Industry Rules of Thumb’ replaced by rigless reasoning as a standard well intervention downhole sand control solution where Medco E&P Natuna Ltd. (Medco E&P) faces sand control challenges in their high deviation, sidetracked well stock. The paper draws final attention to the hydrocarbon performance gain resulting due to the ability for choke free production to allow drawing down the well at higher rates than initially expected from this zone.

JS777

Alloy Digest ◽  
1980 ◽  
Vol 29 (11) ◽  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Austenitic Stainless Steel ◽  
Cost Effective ◽  
Heat Treating ◽  
Steel Company ◽  
High Alloy ◽  
Cost Effective Alternative ◽  
Resistance To Stress ◽  
Nickel Base

Abstract JS777 is a high-alloy, fully austenitic stainless steel developed for applications where corrosive conditions are too severe for the standard grades of stainless steel. It also provides a cost-effective alternative to more expensive nickel-base and titanium-base alloys. It has relatively high resistance to stress-corrosion cracking and to intergranular corrosion. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: SS-377. Producer or source: Jessop Steel Company.

ANCORSTEEL 4300

Alloy Digest ◽  
2009 ◽  
Vol 58 (11) ◽  
Keyword(s):  
Fracture Toughness ◽  
Physical Properties ◽  
Tensile Properties ◽  
Cost Effective ◽  
Heat Treating ◽  
Effective Alternative ◽  
Powder Metal ◽  
Secondary Processing ◽  
Cost Effective Alternative

Abstract Ancorsteel 4300 alloy ferrous powder simulates wrought steel compositions and is a cost-effective alternative to alloys requiring secondary processing. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as fracture toughness. It also includes information on heat treating and powder metal forms. Filing Code: SA-611. Producer or source: Hoeganaes Corporation.

scholarly journals OP0198-HPR A STRUCTURED MODEL FOR OA CARE IN PRIMARY HEALTHCARE IS A COST-EFFECTIVE ALTERNATIVE COMPARED TO USUAL CARE FOR PEOPLE WITH HIP AND KNEE OA

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 119-120
Author(s):  
N. Østerås ◽  
E. Aas ◽  
T. Moseng ◽  
L. Van Bodegom-Vos ◽  
K. Dziedzic ◽  
...  
Keyword(s):  
Usual Care ◽  
Primary Healthcare ◽  
Intervention Group ◽  
Cost Effective ◽  
Cost Utility ◽  
Control Group ◽  
Structured Model ◽  
Knee Oa ◽  
Cost Effective Alternative ◽  
The Cost

Background:To improve quality of care for patients with hip and knee osteoarthritis (OA), a structured model for integrated OA care was developed based on international treatment recommendations. A previous analysis of a cluster RCT (cRCT) showed that compared to usual care, the intervention group reported higher quality of care and greater satisfaction with care. Also, more patients were treated according to international guidelines and fulfilled recommendations for physical activity at the 6-month follow-up.Objectives:To assess the cost-utility of a structured model for hip or knee OA care.Methods:A cRCT with stepped-wedge cohort design was conducted in 6 Norwegian municipalities (clusters) in 2015-17. The OA care model was implemented in one cluster at the time by switching from “usual care” to the structured model. The implementation of the model was facilitated by interactive workshops for general practitioners (GPs) and physiotherapists (PTs) with an update on OA treatment recommendations. The GPs explained the OA diagnosis and treatment alternatives, provided pharmacological treatment when appropriate, and suggested referral to physiotherapy. The PT-led patient OA education programme was group-based and lasted 3 hours followed by an 8–12-week individually tailored resistance exercise programme with twice weekly 1-hour supervised group sessions (5–10 patients per PT). An optional 10-hours Healthy Eating Program was available. Participants were ≥45 years with symptomatic hip or knee OA.Costs were measured from the healthcare perspective and collected from several sources. Patients self-reported visits in primary healthcare at 3, 6, 9 and 12 months. Secondary healthcare visits and joint surgery data were extracted from the Norwegian Patient Register. The health outcome, quality-adjusted life-year (QALY), was estimated based on the EQ-5D-5L scores at baseline, 3, 6, 9 and 12 months. The result of the cost-utility analysis was reported using the incremental cost-effectiveness ratio (ICER), defined as the incremental costs relative to incremental QALYs (QALYs gained). Based on Norwegian guidelines, the threshold is €27500. Sensitivity analyses were performed using bootstrapping to assess the robustness of reported results and presented in a cost-effectiveness plane (Figure 1).Results:The 393 patients’ mean age was 63 years (SD 9.6) and 74% were women. 109 patients were recruited during control periods (control group), and 284 patients were recruited during interventions periods (intervention group). Only the intervention group had a significant increase in EQ-5D-5L utility scores from baseline to 12 months follow-up (mean change 0.03; 95% CI 0.01, 0.05) with QALYs gained: 0.02 (95% CI -0.08, 0.12). The structured OA model cost approx. €301 p.p. with an additional €50 for the Healthy Eating Program. Total 12 months healthcare cost p.p. was €1281 in the intervention and €3147 in the control group, resulting in an incremental cost of -€1866 (95% CI -3147, -584) p.p. Costs related to surgical procedures had the largest impact on total healthcare costs in both groups. During the 12-months follow-up period, 5% (n=14) in the intervention compared to 12% (n=13) in the control group underwent joint surgery; resulting in a mean surgical procedure cost of €553 p.p. in the intervention as compared to €1624 p.p. in the control group. The ICER was -€93300, indicating that the OA care model resulted in QALYs gained and cost-savings. At a threshold of €27500, it is 99% likely that the OA care model is a cost-effective alternative.Conclusion:The results of the cost-utility analysis show that implementing a structured model for OA care in primary healthcare based on international guidelines is highly likely a cost-effective alternative compared to usual care for people with hip and knee OA. More studies are needed to confirm this finding, but this study results indicate that implementing structured OA care models in primary healthcare may be beneficial for the individual as well as for the society.Disclosure of Interests:None declared

scholarly journals Optical spin-symmetry breaking for high-efficiency directional helicity-multiplexed metaholograms

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Muhammad Ashar Naveed ◽  
Muhammad Afnan Ansari ◽  
Inki Kim ◽  
Trevon Badloe ◽  
Joohoon Kim ◽  
...  
Keyword(s):  
High Efficiency ◽  
Spin Symmetry ◽  
Cost Effective ◽  
Dielectric Materials ◽  
Additional Degree ◽  
Cost Effective Alternative ◽  
Spin Orbit Interactions ◽  
Smart Mobile ◽  
The Cost ◽  
Hydrogenated Amorphous

AbstractHelicity-multiplexed metasurfaces based on symmetric spin–orbit interactions (SOIs) have practical limits because they cannot provide central-symmetric holographic imaging. Asymmetric SOIs can effectively address such limitations, with several exciting applications in various fields ranging from asymmetric data inscription in communications to dual side displays in smart mobile devices. Low-loss dielectric materials provide an excellent platform for realizing such exotic phenomena efficiently. In this paper, we demonstrate an asymmetric SOI-dependent transmission-type metasurface in the visible domain using hydrogenated amorphous silicon (a-Si:H) nanoresonators. The proposed design approach is equipped with an additional degree of freedom in designing bi-directional helicity-multiplexed metasurfaces by breaking the conventional limit imposed by the symmetric SOI in half employment of metasurfaces for one circular handedness. Two on-axis, distinct wavefronts are produced with high transmission efficiencies, demonstrating the concept of asymmetric wavefront generation in two antiparallel directions. Additionally, the CMOS compatibility of a-Si:H makes it a cost-effective alternative to gallium nitride (GaN) and titanium dioxide (TiO2) for visible light. The cost-effective fabrication and simplicity of the proposed design technique provide an excellent candidate for high-efficiency, multifunctional, and chip-integrated demonstration of various phenomena.

scholarly journals Robotic hepatectomy is a safe and cost-effective alternative to conventional open hepatectomy: A single center experience

HPB ◽  
2020 ◽  
Vol 22 ◽  
pp. S186-S187
Author(s):  
J. Hawksworth ◽  
N.P. Llore ◽  
M.L. Holzner ◽  
P. Radkani ◽  
E. Mesler ◽  
...  
Keyword(s):  
Cost Effective ◽  
Effective Alternative ◽  
Single Center ◽  
Robotic Hepatectomy ◽  
Single Center Experience ◽  
Open Hepatectomy ◽  
Cost Effective Alternative

scholarly journals A two-stage amplified PZT sensor for monitoring lung and heart sounds in discharged pneumonia patients

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Hongbin Chen ◽  
Shuai Yu ◽  
Haiyang Liu ◽  
Jie Liu ◽  
Yongguang Xiao ◽  
...  
Keyword(s):  
High Sensitivity ◽  
Cost Effective ◽  
High Ratio ◽  
Heart Sounds ◽  
Two Stage ◽  
Diagnosis And Prognosis ◽  
Sensor Device ◽  
Cost Effective Alternative ◽  
A Charge ◽  
Highly Sensitive Detection

AbstractAssessment of lung and heart states is of critical importance for patients with pneumonia. In this study, we present a small-sized and ultrasensitive accelerometer for continuous monitoring of lung and heart sounds to evaluate the lung and heart states of patients. Based on two-stage amplification, which consists of an asymmetric gapped cantilever and a charge amplifier, our accelerometer exhibited an extremely high ratio of sensitivity to noise compared with conventional structures. Our sensor achieves a high sensitivity of 9.2 V/g at frequencies less than 1000 Hz, making it suitable to use to monitor weak physiological signals, including heart and lung sounds. For the first time, lung injury, heart injury, and both lung and heart injuries in discharged pneumonia patients were revealed by our sensor device. Our sound sensor also successfully tracked the recovery course of the discharged pneumonia patients. Over time, the lung and heart states of the patients gradually improved after discharge. Our observations were in good agreement with clinical reports. Compared with conventional medical instruments, our sensor device provides rapid and highly sensitive detection of lung and heart sounds, which greatly helps in the evaluation of lung and heart states of pneumonia patients. This sensor provides a cost-effective alternative approach to the diagnosis and prognosis of pneumonia and has the potential for clinical and home-use health monitoring.

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