摘要
建立了钻柱失稳的准螺旋模型，并用能量法推导出水平段和弯曲段钻柱的准螺旋失稳临界屈曲载荷，给出了水平段钻柱失稳后的摩阻力计算公式。计算结果表明，钻柱的准螺旋失稳临界载荷小于其完全螺旋失稳临界载荷。弯曲段井壁的约束增大了该段钻柱的刚度，因此，弯曲段钻柱的临界失稳载荷大于水平段的相应载荷值。室内模拟实验研究表明，准螺旋模型计算值与实验值较为接近，计算结果可供实际钻井作业参考。
A similar helix buckling model of drillpipes is presented. The critical buckling loads
of this model in horizontal and curved wells were studied with an energy method. The formulas
for calculating the frictional force between buckled pipes
and wellbore wall in horizontal wells are deduced. The calculation results show that the critical
buckling load of this model is less than that of helix model. The restriction of curved wellbore
wall on drillpipe can enhance its rigidity. So the critical buckling load of drillpipes in curved
wellbore is higher than that in horizontal wellbore. The calculating result of similar helix model
is near to testing value, which shows that this theoretical model is reasonable and can be used
as a reference in field drilling.
出处
《石油大学学报（自然科学版）》
CSCD
1999年第2期55-57,共3页
Journal of the University of Petroleum,China(Edition of Natural Science)
关键词
水平井
钻柱
稳定性
准螺旋失稳
数学模型
horizontal wells
drill stem
stability
similar helix
buckling
frictional force, mathematical model
