The effects of surging and heaving movements of installation platform on mechanical behaviors of SCT installation pipe was studied. Movements of SCT installation platform, ocean wave and current, water depth, SCT weight, installation pipe specification and those dominate the mechanical behaviors of installation pipe and SCT installation precision were considered. The results indicate that surging movement of the platform is the main factor that dominate the deformation of the installation pipe. The surging and heaving movements have significant effect on the tension force loaded on the installation pipe and thus need to be considered when designing SCT installation.
Abstract The effects of surging and heaving movements of installation platform on mechanical behaviors of SCT installation pipe was studied. Movements of SCT installation platform, [...]
The article presents a mathematical model to investigate the operability envelopes for subsea production tress (SPT) installation using drill pipe. The finite differential method was used to solve the established governing equations in which the ocean conditions were considered. Based on the evaluations of the ocean wave, ocean current, water depth, specification of drill pipe and SPT weight that might dominate the mechanical behaviors of the pipe, the operability envelopes with permissible ocean conditions for SPT installation were obtained. The results indicate that changes of depths in deep water and SPT weight have few effects on the operation conditions and it would be better to choose smaller pipe to obtain larger permissible ocean conditions during SPT installation.
Abstract The article presents a mathematical model to investigate the operability envelopes for subsea production tress (SPT) installation using drill pipe. The finite differential [...]
In order to simplify the manufacture of multiphase pump and improve the operating flexibility for gas void fraction (GVF) of the multiphase fluids that the pump transported, an eccentric rotary multiphase pump (ERMP) is presented. In this study, the structural characteristics and working principle of the ERMP are presented first. Then, the kinematic and force models are established for the key components- sliding vane and rotor. The velocity, acceleration, and force equations with shaft rotation angle are derived for each component. Based on the established models, simulations are performed for an ERMP prototype. The simulated results show that the areas opposite the sliding vane and apart from the center of the rotor have larger velocities and wear problem. Moreover, the binding force, pressure difference induced force and the normal force exercise a negative effect on the friction at the sliding vane sides and rotor. Lower shaft speed and smaller eccentric distance of the crankshaft are helpful to reduce this effect. The findings confirm that the proposed ERMP is suitable for multiphase transportation and has a higher mechanical efficiency for its advanced structure and working principle.
Abstract In order to simplify the manufacture of multiphase pump and improve the operating flexibility for gas void fraction (GVF) of the multiphase fluids that the pump transported, [...]
Effects of surging and heaving movements of platform on mechanical behaviors of SCT installation pipe 
