Risk Assessment And Analysis Of Offshore Production Platform In Chengdao Oilfield

From 1960s to early twenty-first Century,the global total of more than 7000 units were built offshore platform,with the platform of the passage of time gradually old,but the crude oil formation has not been mined over,therefore,how to make the extended service platform on the premise of safety to maximize heat,it is particularly important.This paper takes a production platform of Chengdao Oilfield as the research object,and carries on the risk assessment and analysis of its overdue service.First,the thickness of the steel plate of the main bearing members after corrosion is measured by ultrasonic testing method,and the corrosion degree of the components is determined,and the data after corrosion are collected.Because the platform has been built for a long time and has been rebuilt for many years,it will inevitably cause changes in the weight,weight distribution and variable load of the platform.Therefore,the load distribution of the platform should be reconfirmed.Then,the current load distribution platform,leg erosion corrosion data and data platform based on the Ansys finite element software to establish the platform model of finite element analysis,stress analysis platform in the extreme conditions of ice load,extreme storm plate,leg and spud fixing chamber,alignment specification check.Finally established the analysis model of dynamic platform,the platform for obtaining natural vibration frequency and vibration wave,compared with the cycle of platform operation area,analysis platform under wave load resonance in May;according to the seismic response spectrum calculation of seismic cooperation analysis platform under seismic load dynamic response,reliability verification platform under seismic load.The results show that the production platform of 2# and 3# steel pile bearing capacity can not meet the standard requirements,production platform of 3# pile legs instability,which will lead to further exacerbate the platform tilt;solid pile chamber structure especially the fixed pile room and deck joints fatigue strength is insufficient,the need for reinforcement;according to the load reduction platform requires a total load reduction 2.6898MN(274.5T),2# and 3# are mainly distributed in the leg(workover platform side);multiple compartments platform bottom and longitudinal corrosion has found platform status,platform deck corrosion wear,because all is not the main bearing component,can transfer board repair.