关键词: 粘弹性流体, 法向应力, 抽油杆, 偏磨, 扶正器, 大庆油田

Abstract: The working condition of sucker rod under force action became worse,and the partial abrasion of sucker rod has resulted in the break and drop of sucker rods,after polymer flooding put into effect in Daqing Oilfield.The visco-elastic fluid hydrodynamic theory was applied to the wear-resistance experiment on sucker rods.The values of normal stress in suck string generated by visco-elastic fluid and eccentricity brought out by sucker string were measured quantitatively.The partial abrasion of sucker string and tube in oil well was caused from the normal stress of visco-elastic fluid.A module for bending analysis of sucker rod in cross direction and wire direction was developed. Some integrated measures to avoid partial abrasion of sucker string and tube were provided.To add a centralizer between sucker rods and increase of weight at bottom of sucker are beneficial to protect the sucker rods.The use of this method has gained a great economic effect in Daqing Oilfield.

Key words: visco-elastic fluid, normal stress, sucker rod, partial abrasion, centralizer, Daqing Oilfield