公开(公告)号：US06457538B1

公开(公告)日：2002-10-01

申请号：US09789309

申请日：2001-02-20

申请人： Gerard T. Pittard ,  J. Christopher Hetmaniak ,  Curtis Leitko ,  William J. Mcdonald

发明人： Gerard T. Pittard ,  J. Christopher Hetmaniak ,  Curtis Leitko ,  William J. Mcdonald

IPC分类号： E21B2510

CPC分类号： E21B25/10 ,  E21B47/182

摘要： A system of apparatus for use in a coring tool measures the height of a core sample being recovered and transmits data relative thereto to the surface of a formation concurrently during the coring operation. A transmitter of an electromagnetic ranging system rides atop a core sample being formed in the barrel chamber and a receiver member of the electromagnetic ranging system is fixed at a top end of the barrel it known distance above the transmitter. During the coring operation the transmitter transmits a fixed frequency signal to the receiver through drilling fluid disposed therebetween. The distance between the transmitter and receiver decreases and the amplitude of the transmitted signal changes as a function of the separation distance between the transmitter and receiver as the core sample enters the inner barrel and the height of the core sample within the barrel is determined as a function of time and depth. The pressure of the drilling fluid is modulated to transmit a series of pressure pulses from the barrel to the surface encoded to produce a binary digital or pulse-width modulation signal. The electromagnetic ranging system may be incorporated into a coring tool having a core bit disposed at a lower end and a full closure ball valve and core retention assembly movable to a closed position to close the bottom end of the inner barrel and prevent the loss of core collected in the inner barrel chamber.

摘要翻译： 在取芯工具中使用的装置系统测量正在回收的芯样品的高度，并且在取芯操作过程中同时将相对于其的数据传送到地层的表面。 电磁测距系统的发射器在形成在筒室中的芯样品的顶部上方，并且电磁测距系统的接收器构件固定在其在发射器上方已知距离的筒的顶端。 在取芯操作期间，发射器通过设置在其间的钻井液将接收机传输固定频率信号。 当核心样品进入内筒时，发射器和接收器之间的距离减小，并且发射信号的幅度随着发射器和接收器之间的间隔距离的变化而变化，并且将筒体内的芯样品的高度确定为 时间和深度的功能。 调节钻井液的压力以将一系列压力脉冲从筒体传送到编码的表面，以产生二进制数字或脉冲宽度调制信号。 电磁测距系统可以结合到具有设置在下端的芯钻头的取芯工具和全闭合球阀和芯保持组件可移动到关闭位置以封闭内筒的底端并防止芯损失 收集在内桶腔中。