专利内容由知识产权出版社提供
专利名称：METHODS AND APPARATUS FOR
MEASURING A LENGTH OF CABLE
SUSPENDING A WELL LOGGING TOOL IN ABOREHOLE
发明人：Robert A. Broding申请号：US06/469592申请日：19830224公开号：US04597183A公开日：19860701
摘要：Methods and apparatus are disclosed for measuring a length of logging cableintroduced into a borehole, thereby measuring the depth of a logging tool, or sonde,attached to the lower end of the cable. The methods involve producing an electricalsignal, which propagates along the cable, and detecting at the mouth of the borehole thetime of passage of the initial electrical signal and the time of passage of a subsequentelectrical signal reflected or returned upwardly from the lower end of the cable, or,alternatively, the time of arrival of the reflected or returned electrical signal at the upperend of the cable. These times can be determined by means of clocks which are switchedon by the passage of the initial electrical signal and switched off by the subsequentelectrical signal. Knowing the time intervals and the velocity of propagation of electricalsignals in the cable, the length of cable from the mouth of the borehole to the lower endof the cable, and thus the depth of the sonde, is measured. Various embodiments ofapparatus including electrical signal detectors which do not electrically contact the cableare disclosed for sensing the electrical signals necessary for measuring the length of
cable introduced into the borehole, and thus the depth of the sonde.
申请人：STANDARD OIL COMPANY (INDIANA)
代理人：Timothy D. Stanley
更多信息请下载全文后查看
