Silicone Rubber Drill Riser: Handle Drastic Conditions at Reduced Costs

摘要

Risers are considered to be the most critical product in offshore pipeline development taking into account the dynamic loads and sour service conditions they need to withstand. The idea aims at providing a design where the riser is equipped with shock absorbent and thermally insulating material rather than increasing the steel layers around it (conventional method) for making it withstand notorious conditions combined with increased lifetime. Modification in the existing riser design includes reduction in the steel thickness of the riser, addition of an external high carbon steel casing (of larger diameter) around the outermost layer of the riser and accommodation of a filler material between the reduced outermost steel layer and the added outer steel casing. The filler material used is silicone rubber blended with microballoons (hollow glass microspheres usually of diameter 100 nm – 5 mm), which is non-reactive, corrosion resistant, stable to extreme environments, resistant to high pressure, high temperature and shear force. This will bring to you a riser that can withstand very high pressure and temperature. A brief comparison between silicone rubber riser and conventional steel riser is presented in the paper. The economics of the method, and the method itself, is compared to the current riser design. The proposed riser design's cost effectiveness lies in the fact that the layers of the riser being protected by highly resistant silicone-rubber are saved from outer corrosion and other damaging factors, therefore increasing their life and providing reusability. Also, the microballoons used to blend the silicone rubber are produced as waste product in coal fired power stations, hence prove to be economical. The novelty lies in the fact that the proposed riser design provides enhanced properties when compared to the conventional drill riser and also won't add up being a burden on any companies' economics provided its cost effectiveness.