煤层气井杆管偏磨规律及偏磨防治技术

从偏磨井实际资料入手,运用煤层气开发学、统计学等方法,研究了煤层气井杆管偏磨特征和偏磨规律,并探讨了煤层气井杆管偏磨防治措施。研究发现:杆管偏磨是煤层气井排采中普遍存在的问题;杆管偏磨的位置基本上都在泵体以上的200 m有限范围之内;偏磨基本上发生在排采1 a时间之内,并且在随后的排采时间里偏磨程度有所减轻;井眼弯曲、井深大于500 m的井以及抽采冲次大于3次/min的井比较容易发生偏磨;产出液中的酸性成分和煤粉也能加速杆管偏磨程度。分析认为,优选煤层气井排采设备,合理控制煤层气井排采参数,以及针对煤层气井的自身特点采取一些综合防治措施,是防治煤层气井杆管偏磨的主要手段。

Rod and tubing eccentric wear regularities and eccentric wear prevention and control techniques in CBM well

Based on the actual data of eccentric wear wells, rod and tubing eccentric wear characteristics and regularity of CBM wells were studied by using the methods of CBM development theory and statistics, and the prevention and control measures of rod and tubing eccentric wear of CBM wells are actively discussed. Studies suggest that rod and tubing eccentric wear problem is widespread in the process of production of CBM wells, and the eccentric wear location is about 200 m higher than the pump basically, rod and tubing eccentric wear happens not longer than one year from the production, and the eccentric wear degree eases with time. This phenomenon is more prone to occur in inclined wells, deep wells with depth of more than 500m and wells with punching number of more than 3 times/min. In addition, acid composition in produced fluid and coal powder help to accelerate rod and tubing eccentric wear speed. Optimization of production equipments, reasonable control of production parameters and taking comprehensive prevention and control measures according to the CBM wells characteristics are considered to be the main prevention and control means of rod and tubing eccentric wear in CBM wells.