摘要
水平井水平段钻进的钻柱具有独特性,且钻进时传输的井下信息量大,传输速度要求高,因此探索在水平井内利用声波来传输井下信息非常必要。利用有限差分法对加重钻杆及普通钻杆内声波传播的频谱结构进行了计算分析,对φ127.0 mm加重钻杆及普通钻杆、φ139.7 mm加重钻杆及普通钻杆中声波传播的频谱结构差异进行对比,探讨了材料差异对声波频谱的影响。研究结果表明,相同材料加重钻杆的频谱结构与普通钻杆相比,阻带宽度产生变化,通带中心位置基本不变;2种结构通带的交集随着频率的降低而增大;通带顶端毛刺的波度幅值变大、数量变少。φ127.0 mm加重钻杆与φ139.7 mm加重钻杆的频谱结构基本无差异。加重钻杆材料差异导致频谱结构变化较大,实际选频中不可忽略此差异。水平井钻柱中传输井下信息声载波的频率应该全面考虑上述因素,选择在频谱结构中通带的交集范围之内。
The unique feature of the drill string for the horizontal section drilling, the large amount of infor- mation transmitted while drilling and the transmission speed requirements provide the necessity to study on the hori- zontal well information transmission using sound waves. The spectrum structure of acoustic wave propagation in the HWDP and conventional drillpipe are calculated and analyzed by using the finite difference method. The spectrum structure of acoustic wave propagation in the 0127.0 mm and ~139. 7 mm HWDP and conventional drillpipe are compared. The effect of material on the acoustic spectrum are discussed. The results show that, compared with the conventional drillpipe, the spectrum structure of the HWDP with the same material has a different stop band width and a substantially unchanged center of the passband. With the decrease of frequency, the passband intersection of the two kinds of structures increases, the wave amplitude of the passband top burr becomes larger, but the number of the passband top burr is reduced. There is almost no difference between the spectrum structure of the ~127.0 mm HWDP and the ~139.7 mm HWDP. The material of the HWDP has a great effect on the spectrum structure, which must be considered in frequency selection. The above factors should be taken full account when selecting frequency of the sound for information transmission in horizontal well drill string. The frequency should be in the range of thepassband intersection.
出处
《石油机械》
北大核心
2014年第12期6-10,16,共6页
China Petroleum Machinery
基金
国家863计划项目"低压易漏地层钻井关键技术及装备"(2012AA091601)
国家自然科学基金项目"钻柱信道内多源激励声信号的特性表征与识别检测"(51404285)
中国博士后科学基金面上资助项目"井下随钻信息声传输系统研制与应用研究"(2014M551985)
关键词
水平井
钻柱
井下信息声传输
加重钻杆
通带
horizontal well
drillstring
downhole acoustic information transmitting
HWDP
passband
