Focusing on the extending length restriction of the completion screen pipe resistance running into ultra-short radius horizontal well,this paper proposed technology of hydraulic drive completion tubular string running...Focusing on the extending length restriction of the completion screen pipe resistance running into ultra-short radius horizontal well,this paper proposed technology of hydraulic drive completion tubular string running into ultra-short radius horizontal well.Innovative hydraulic drive tools and string structure are designed,which are composed of guide tubing,hydraulic drive tubing and non-metallic completion screen pipe from inside to outside.A novel mechanical-hydraulic coupling model is established.Based on the wellbore structure of an ultra-short radius horizontal well for deep coalbed methane,the numerical calculations of force and hydraulic load on tubular strings were accomplished by the mechanical-hydraulic coupling model.The results show that the extending length of completion tubular string with the hydraulic drive is 17 times that of conventional completion technology under the same conditions.The multi-factor orthogonal design is adopted to analyze the numerical calculations,and the results show that the extending length of the completion tubular string is mainly affected by the completion tubular string structure and the friction coefficient between the non-metallic composite continuous screen pipe and the wellbore.Two series of hydraulic drive completion tubular string structures suitable for ultra-short radius horizontal wells under different conditions are optimized,with the extending limits of 381 m and 655 m,respectively.These researches will provide theoretical guidance for design and control of hydraulic drive non-metallic composite continuous completion screen pipe running into ultra-short radius horizontal wells.展开更多
针对松软煤层顺层抽采钻孔施工中存在的筛管全程下入困难、直径受限等问题,借鉴井巷工程反井施工工艺技术特点,结合回采工作面顺层钻孔施工作业条件,提出了回采工作面顺层抽采钻孔大直径反扩孔联合下筛管技术。根据大直径反扩孔联合下...针对松软煤层顺层抽采钻孔施工中存在的筛管全程下入困难、直径受限等问题,借鉴井巷工程反井施工工艺技术特点,结合回采工作面顺层钻孔施工作业条件,提出了回采工作面顺层抽采钻孔大直径反扩孔联合下筛管技术。根据大直径反扩孔联合下筛管技术特点,研发了相应的反扩孔钻头。在金岩煤矿20603工作面进行了现场试验,成功施工了2个Φ250 mm大直径抽采钻孔,实现了Φ180 m m PVC大直径筛管在顺层钻孔的全程护孔作业。现场实践表明:回采工作面顺层抽采钻孔大直径反扩孔联合下筛管技术可以实现“大直径钻孔成孔和大直径筛管护孔”目标,能够有效提高顺层钻孔抽采效果。抽采钻孔大直径反扩孔联合下筛管技术为大直径抽采钻孔施工及护孔技术提供新的思路,为松软煤层回采工作面高效瓦斯抽采提供创新解决方案。展开更多
The objective of the present experimental work is to investigate the performance of a wrapped screen heat pipe for atmospheric air heating to compare with the limits of this pipe. The experiment was conducted using co...The objective of the present experimental work is to investigate the performance of a wrapped screen heat pipe for atmospheric air heating to compare with the limits of this pipe. The experiment was conducted using copper pipe material and acetone as working fluid at different vapor temperatures. The testing also consists of a heater, a blower for heat removal (condenser), temperature measuring device, a vapor temperature probe, acetone charging system, and a vacuum pump. The copper outside diameterof the pipe is 0.022 m, with a total length of 0.6 m. The results showed that the pipe wall temperature (Tw) for a wrapped screen heat pipe has a rapid increase and takes 50 min to reach steady state at (Q = 63 W). The vapour temperature of working fluid increases as the heat load increases at constant air velocity. It was also been found that the range of vapour temperature deceases as the filling ratio increases that means the increasing of the filling ratio results the decrease of the maximum vapour temperature and the variation in the vapour temperature. The best recorded filling ratio is 0.6 which has the lowest vapour temperature at highest heat load. The maximum heat transport limit for this pipe is 80 W and the maximum temperature difference for air is 5。C.展开更多
基金Supported by the Innovative Research Group Project of China National Natural Science Foundation(51821092)Key Project of China National Natural Science Foundation(U1762214).
文摘Focusing on the extending length restriction of the completion screen pipe resistance running into ultra-short radius horizontal well,this paper proposed technology of hydraulic drive completion tubular string running into ultra-short radius horizontal well.Innovative hydraulic drive tools and string structure are designed,which are composed of guide tubing,hydraulic drive tubing and non-metallic completion screen pipe from inside to outside.A novel mechanical-hydraulic coupling model is established.Based on the wellbore structure of an ultra-short radius horizontal well for deep coalbed methane,the numerical calculations of force and hydraulic load on tubular strings were accomplished by the mechanical-hydraulic coupling model.The results show that the extending length of completion tubular string with the hydraulic drive is 17 times that of conventional completion technology under the same conditions.The multi-factor orthogonal design is adopted to analyze the numerical calculations,and the results show that the extending length of the completion tubular string is mainly affected by the completion tubular string structure and the friction coefficient between the non-metallic composite continuous screen pipe and the wellbore.Two series of hydraulic drive completion tubular string structures suitable for ultra-short radius horizontal wells under different conditions are optimized,with the extending limits of 381 m and 655 m,respectively.These researches will provide theoretical guidance for design and control of hydraulic drive non-metallic composite continuous completion screen pipe running into ultra-short radius horizontal wells.
文摘针对松软煤层顺层抽采钻孔施工中存在的筛管全程下入困难、直径受限等问题,借鉴井巷工程反井施工工艺技术特点,结合回采工作面顺层钻孔施工作业条件,提出了回采工作面顺层抽采钻孔大直径反扩孔联合下筛管技术。根据大直径反扩孔联合下筛管技术特点,研发了相应的反扩孔钻头。在金岩煤矿20603工作面进行了现场试验,成功施工了2个Φ250 mm大直径抽采钻孔,实现了Φ180 m m PVC大直径筛管在顺层钻孔的全程护孔作业。现场实践表明:回采工作面顺层抽采钻孔大直径反扩孔联合下筛管技术可以实现“大直径钻孔成孔和大直径筛管护孔”目标,能够有效提高顺层钻孔抽采效果。抽采钻孔大直径反扩孔联合下筛管技术为大直径抽采钻孔施工及护孔技术提供新的思路,为松软煤层回采工作面高效瓦斯抽采提供创新解决方案。
文摘The objective of the present experimental work is to investigate the performance of a wrapped screen heat pipe for atmospheric air heating to compare with the limits of this pipe. The experiment was conducted using copper pipe material and acetone as working fluid at different vapor temperatures. The testing also consists of a heater, a blower for heat removal (condenser), temperature measuring device, a vapor temperature probe, acetone charging system, and a vacuum pump. The copper outside diameterof the pipe is 0.022 m, with a total length of 0.6 m. The results showed that the pipe wall temperature (Tw) for a wrapped screen heat pipe has a rapid increase and takes 50 min to reach steady state at (Q = 63 W). The vapour temperature of working fluid increases as the heat load increases at constant air velocity. It was also been found that the range of vapour temperature deceases as the filling ratio increases that means the increasing of the filling ratio results the decrease of the maximum vapour temperature and the variation in the vapour temperature. The best recorded filling ratio is 0.6 which has the lowest vapour temperature at highest heat load. The maximum heat transport limit for this pipe is 80 W and the maximum temperature difference for air is 5。C.
