The Fuzzy Comprehensive Evaluation Method For Evaluation Of The Safety Of The Marine Riser

Marine riser as connecting the water floating catheter device and underwater equipment, widely used in the deep water development, due to the Marine riser special construction technology and harsh Marine environment riser under construction process of large stress and the Marine environment of the environmental load, riser become important in the whole of the Marine pipeline system and the weak part. In recent years the Marine riser failure cause huge economic losses, the Marine environment pollution accident, the safety of the Marine riser received extensive attention of the industry.The oil and gas pipeline risk assessment technology abroad since the1970s with the oil and gas pipelines after entering aging stage began to grow, and it has very strong pertinence and practicality. Since1995the introduction of the technology in our country, many scholars have done a lot in land oil and gas pipelines in the applied research, has obtained certain research results and in the specific application has achieved good economic benefits. In the play an important role in the development of offshore oil and gas fields, the application of Marine riser is starts late. Scientific and reasonable evaluation technique is helpful to reduce the risk of accidents bring huge economic losses and casualties, to develop scientific and reasonable safety maintenance plan provides strong scientific basis. Therefore, the research content of this article is mainly for the Marine riser system of risk evaluation research.First of all, the Marine riser information collection, the historical accident data of Marine riser at home and abroad, this paper compares and analyzes high-risk area, find out the Marine riser, Marine riser failure of the main risk factors. Corrosion caused by accidents accounted for43%of the riser, the main failure area for riser splash zone. Therefore, splash zone of the stand pipe should be as risk evaluation should focus on the parts. Indicates that the risk factors of Marine riser mainly include natural load, third-party damage, misoperation, corrosion and other factors. For later provides the reference for the risk evaluation index system of the Marine riser.Through comparison and analysis risk assessment method, in view of the Marine riser of correlation between risk factors and the quantitative characteristics, find out suitable Marine riser risk assessment methods. Establish a Marine riser risk evaluation index system, analysis the influence factors of Marine riser, the introduction of the unascertained risk evaluation method, quantitative classification of risk indicators, based on the unascertained measurement function, constructing the Marine riser risk assessment was item index measurement and multi-index model. Combined with fuzzy comprehensive evaluation method for a certain area of riser is evaluated. In this paper, we establish evaluation matrix method compared with conventional method has the following characteristics:(1) can to a great extent, such as reducing the score of subjective factors.(2) based on some indicators (such as sea ice, earthquake, etc.) of quantitative classification and evaluation process is more abstract, in the concrete use, save time and manpower.Finally by an example of a sea of Marine pipeline risk assessment, identified the Marine riser level of risk.