【摘要】 渤海某海洋平台配置的ZJ50/3150DB海洋钻机在钻井作业时井架振动幅度较大,为了评估井架在钻井作业时的安全性,对井架进行了振动检测,并建立了井架结构有限元模型,结合现场检测数据和模型计算结果分析井架振动对井架结构安全的影响。分别进行了井架固有频率检测、钻进作业工况井架幅频响应检测、井架振动幅值检测和井架振动加速度检测;依据井架图纸及现场井架实际情况,采用ANSYS软件建立了井架结构有限元模型。使用该模型计算出的井架第1阶固有频率为0.555 8 Hz,与现场检测结果较吻合,验证了模型的正确性。分析现场检测数据和模型计算结果发现:顶驱转速为36 r/min时,井架易发生共振;井架C型开口抗扭强度低;井架底座2个前撑杆为关键构件,其结构安全性影响整个井架安全;各种工况下的井架振动和顶驱通过二层台时引起的井架冲击振动均符合安全要求。更多还原

【Abstract】 The rig derrick of a ZJ50/3150DB drilling rig in an offshore jacket platform located in the Bohai bay vibrates obviously when drilling.In order to assess the safety of the derrick when drilling,vibration test for the derrick was carried out and a finite element model of the derrick was built to analyze the impact of vibration on the derrick’s structure safety,in combination of the field test data with the calculation results got using the model.Natural frequency,amplitude-frequency response when drilling,vibration amplitude and vibration acceleration of the derrick were tested.Based on the derrick drawing and field situation,the finite element model of the derrick structure was built using ANSYS software.The first-order natural frequency of the derrick calculated using the model was 0.555 8 Hz,which coincided with the filed test data and proved the validity of the model.The analysis of the field test data and the calculation results,show,the derrick is resonance-prone when the rotation speed of the top drive is 36 r/min,the derrick C-style opening has low torsional strength,the two front brace rods of the derrick substructure are crucial components that concern the derrick safety,and derrick vibrations under different working conditions and shock vibration happening when the top drive passing by the monkey board meet safety requirements.更多还原