During the horizontal well and the directional well extraction process, vitta and the oil-pole joint and the centralizer frequently have the contact which makes the vitta have the lopsided abrasion.

• 在水平井和定向井的采油过程中,油管内壁和运动的油杆接箍及扶正器之间经常发生接触,使油管内壁发生偏磨。文中将偏磨油管的破裂强度问题看作失稳问题,应用弹塑性有限元方法分析了偏磨油管的破裂强度。