摘要
目前煤层气勘探取样常采用普通的绳索打捞取心钻具获取样品,并通过获取的样品解析结果来评价目标层的储气量。在取样过程和煤心转移过程中,随着外界压力的降低,加快了煤心中煤层气的逸散,从而无法准确评价目标地层的储气量。针对这一问题,项目组研制了煤层气保压取心钻具,在获取煤心的过程中,保压筒始终保持取样处的压力,并且保压筒可直接与解析设备连接,避免常规取样过程中煤层气的逸散,提高解析数据的准确性,从而为煤层气储量评价提供精确的依据。通过取心钻具的结构设计、保压筒的耐压设计、加工试制和保压测试表明,保压取心钻具取心直径为85mm,最大耐压能力为20Mpa,保压两个小时压力损失不超过最大耐压值的7%,达到了设计和使用要求。
At present,the general wire-line tool is commonly used to collect core samples in coal-bed gas exploration.And the gas storage capacity of coal beds is evaluated by analysis of the obtained cores.In the process of sampling and core-transfer,dissipation of the gas would be accelerated with the lowering outside pressure,thus making it difficult to evaluate the gas reserve of the target beds accurately.To solve this problem,a pressure-holding core tool for coal-bed gas is developed.During the sampling process,the pressure-holding sleeve keeps the same pressure as that at the position where the core sample is obtained.And this sleeve can be connected with test equipment directly,avoiding the gas dissipation from cores.These data are accurate basis for evaluation of Coal bed methane reserves.Through the structure design,pressure design,manufacture and pressure test of pressure-barrel,it is shown that the coring diameter of the pressure sample drill is 85mm,and the maximum pressure holding capacity is 20Mpa,the pressure loss of the pressure holding for two hours is not more than 7%of the maximum pressure holding value,which meets the design and use requirements.
作者
李小洋
张永勤
王汉宝
梁健
尹浩
刘亚姣
周阳
LI Xiaoyang;ZHANG Yongqin;WANG Hanbao;LIANG Jian;YIN Hao;LIU Yajiao;ZHOU Yang(Institute of Exploration Technology,Chinese Academy of Geological Sciences,Langfang,Hebei065000;Shanghai Jintai Engineering Machinery Co. LTD,Shanghai201805;Survey and Design Research Institute of Northeast Coal Geology Bureau,Shenyang,Liaoning110013)
出处
《地质与勘探》
CAS
CSCD
北大核心
2019年第4期1045-1050,共6页
Geology and Exploration
基金
陆域冻土区天然气水合物钻采技术方法集成(编号:DD20160225)
海域天然气水合物钻探保压与非保压取心技术(编号:GZH201500602-01)联合资助
关键词
煤层气
保压取心
耐压设计
保压测试
coal-seam gas
pressure-holding coring
compression-resistance design
pressure-holding test
