SUBSURFACE PIPE DIMENSION AND POSITION INDICATING DEVICE

摘要

A sensing system provides real time information as to the location of a stand in a tubular string at a predetermined elevation such as where the rams are located. This allows a determination of whether the upsets are aligned with the ramps or whether the stand is aligned with the rams in a manner that the rams will close on the tubular between the end upsets. The surrounding pipe has circumferentially spaced transmitters and receivers to allow a determination of the outer dimension of the pipe and to transmit such information to the surface by conductors or other means. The position of a tubular in an open hole can also be determined by sending a signal from the tubular to the open hole and back to the tubular. Different signal regimes are contemplated as well as power supply options.