Research On Load-bearing Capacity And Safety Evaluation Of The ZJ15DB₅ Derrick And Substructure

Rig system's safety operation is very important in drilling process. Derrick and substructure is the key parts, which safety property is important to production safety of whole derrick system, that is integrated the assessment derrick system safety operation project. Rigs derrick and substructure may have different degree defects and defacements because of disassembly and assembly,conveying,over load and corrosion in production process, the defects and defacements make bearing capacity of derrick and substructure lower than design degree, that makes safety load unknown and production safety hidden trouble. For making sure rig safety operation in drilling process, it has important meaning to assessment bearing capacity of rigs derrick and substructure.The paper first simplify derrick member as the spatial beam element, in view of the ZJ15DB5 rigs derrick and the substructure, carries on the static analysis under the drilling operating using the ANSYS finite element analysis, obtains the derrick and substructure's stress and displacement distributes under this operating, determinants obtained stress whether in its rated load scope, structure whether to satisfy the intensity request. Along with it, the paper carries on the static analysis to the ZJ15DB5 rigs derrick and substructure under the lift operating, obtains derrick and substructure's stress,displacement change in lift process, as well as the lift angle when presents the biggest stress and displacement. Then, the paper studies the rigs derrick test data gathering and the analysis, introduces the primary coverage of derrick test technology and derrick test date gathering and analysis, and carries on the test data gathering and analysis to using ZJ15DB5 rigs derrick. Finally, it studies the revision method of derrick initial flaw and safety assessment theory, and carries on the safety assessment to the ZJ15DB5 rigs derrick.The paper evaluates the bearing capacity of the ZJ15DB5 rigs derrick and substructure, using the method which unify the structure finite element analysis and the scene test, determines it whether can be used safely, provides the reference to the using derrick and new derrick bearing capacity and reliable appraisal, will has the great significance to make the safety assessment system theory careful and thorough.