Abstract: China has successively installed hundreds of offshore oil jacket platforms in the Bohai Sea since the 1980s. Since many jacket platforms have a service life close to the original design life,they are facing new different risks. In order to ensure that these platforms can continue to operate normally,various indicators of the in service jacket platform are tested,and the life extension calculation analysis of the platform is carried out according to the test results. Based on the calculation and analysis results,different corresponding countermeasures are taken for the platform. This paper describes and introduces the relevant main contents such as the detection index of the overall structure of the platform,the calculation analysis of the platform life extension,and the corresponding measures,so as to provide a reference for the life extension evaluation of the Bohai jacket platforms facing the expiration of service.

Key words: risk, platform detection, calculation analysis, life extension, countermeasures