摘要
根据石油钻机井架的结构特点，采用有限元方法对井架结构进行有限元离散，采用单轴向受拉或受压杆单元进行绷绳模拟，并在不同数值范围内施加预紧力，通过对6种工况下石油钻机井架动态特性的计算，分析绷绳预紧力对井架动态特性的影响。分析结果表明，绷绳预紧力对井架前3阶固有频率影响较大，对3阶以上的高阶自振频率影响较小；当绷绳预紧力小于3kN时，绷绳预紧力对井架固有频率的影响可以忽略；在3～20kN范围内，随绷绳预紧力增大井架各阶固有频率也增加，低阶频率增幅明显；当绷绳预紧力超过20kN时，随着预紧力的继续增大，井架振动频率将不受预紧力变化的影响。
According to the structural feature of oil rig derrick, the finite element method was used to conduct the finite element discretization of derrick structure. The uniaxially pulled or compressed rod unit was adopted to conduct the guy rope simulation. The pre-tightening force was applied within different numerical ranges. Through calculation of the dynamic property of the derrick in six operating conditions, the effect of guys＇ pre-tightening force on derrick＇ s dynamic property was analyzed. The analysis shows that guys＇ pre-tightening force has remarka- ble effect on the natural frequency of derrick within its first three orders. It has slight effect on the high-order natural vibration frequency above the third order. When guys＇ pre-tightening force is less than 3 kN, its effect on derrick＇ s natural frequency is negligible. Within the scope of 3 - 20 kN, the natural frequencies of derrick＇ s orders will increase with the increase of guys＇ pre-tightening force, and the low-order frequencies increase remarkably. When guys＇ pre-tightening force goes beyond 20 kN, with the continuous increase of pre-tightening force, derrick＇ s vibration frequency will not be influenced by the change of pre-tightening force.
出处
《石油机械》
北大核心
2014年第1期40-43,共4页
China Petroleum Machinery
基金
河南省自然科学研究项目"石油钻机井架安全运行机理及疲劳寿命可靠性研究"(2010A130001)
关键词
石油钻机
井架绷绳
预紧力
固有频率
动态特性
有限元分析
oil rig
derrick guy
pre-tightening force
natural frequency
dynamic property
finite analysis
