Abstract:
Severe environment of steam flooding producers in the Shengli Oilfield,such as high temperature and high H2S content of produced liquid,sanding and scaling,has caused a range of problems including lifting system corrosion,low pump efficiency,and stuck pumps.To solve these quite diverse problems,we conducted study on the efficient lifting supporting technologies used in the steam flooding producers.It was found that the adaptability of pumping unit and wellhead sealing device could be improved through structure modification and parameters optimization.Using finite element simulation analysis,the seal gap between pump cylinder and the plunger was optimized.In addition,HTHP materials testing could help optimize the pump valve ball and seat,and improve the sealing for the plunger and cylinder under high temperature.High-temperature resistant and anti-corrosion polished rod sealing technology was developed by optimizing the structure and packing materials.The pilot test demonstrated that the innovated supporting device for sucker rod pump lifting maintained good performance under 200℃ at pump setting depth and 170℃ at wellhead.The technology has been applied in 58 wells with the longest production period over 896 days.The period of the pump inspection was extended by 207 days on average,and replacement of the packing was reduced 82 times.Pump efficiency increased by 9.2% on average,and the average daily oil production increased by 0.7 tons.The study results show that the efficient lifting supporting technologies can effectively solve the problems of corrosion and stuck pumps in steam flooding wells with remarkable improvement in oil production and wide application prospects.