In recent years, the production of oil and gas has been developed in deep water depths which exceed 500m. Deep water developments are being followed strongly in different parts of the world (Caspian Sea, Gulf of Mexico, etc.). The movement of floater causes severe stress at the touchdown point (TDP) in steel catenary risers (SCR). The main objective of this study was to simulate the exact behav...

This paper investigates the integrated riser/vessel system which is subjected to random waves. Riser pipelines are the main components of the oil and gas offshore platforms. Whereas Iran country has been located on the fringes of Caspian Sea deep water, therefore study and research in this area is increasingly essential. The fluctuation of floating production causes the severe response and grea...

A steel catenary riser (SCR) attached to a floating platform at its upper end encounters fluctuations in and near its touchdown zone (TDZ), which causes the interaction with the seabed. Subsea surveys and the analysis of SCR’s indicated that the greatest stress and highest damage occurred near the touchdown point (TDP), where the SCR first touches the seabed. Nowadays, the linear seabed spring ...

In the hilly regions of China, developing sustainable agriculture requires implementing conservation management practices that prevent soil erosion and conserve soil and water resources. In the semiarid northwest Loess Plateau, the primary conservation management practice is terracing. Numerical simulation of soil water dynamics in terraces is potentially an efficient means of investigating the...

Several factors can affect the response of steel catenary risers (SCR) around its touch down zone (TDZ). These include stiffness soil, soil suction force on riser TDZ, degradation with cyclic TDZ loading, etc. Riser strength and fatigue computation are usually performed considering flat seabed use rigid or linear (spring) interaction model. However, bathymetric information obtained for SCR lay ...

This doctoral thesis presents new research results on the control of top tensioned risers in deep waters. The main motivation for this work is the development of a riser control system which control the top tension of the individual risers in an array, such that collisions between adjacent risers are prevented. The risk of collision increases with increasing water depth, and as the oil and gas ...

The optimal design of risers for castings has been the subject of numerous investigations and this paper determines the optimal dimensions when Chvorinov’s rule for solidification is obeyed by both the riser and casting and solidification time is the only constraint involved .This problem can be formulated to minimize the riser volume subject to the constraint that the riser solidification time...

A brief review of recent literature on riser design is presented and a concise description of the design process is given. Effects of hydrodynamical design parameters on marine flexible riser design are then reviewed. Riser dynamic analyses are described which substantiate design criteria for the selection of riser configuration in deep and shallow water. The results of dynamic analyses using c...