摘要:
A multi-component sensor of a fluid-borne acoustic wave that senses pressure and up to three orthogonal particle motion components. The sensor is unresponsive to motion of the sensor mount. Furthermore, the sensor is substantially unresponsive to the turbulent flow of the acoustic medium past the sensor.
摘要:
An internal device for use in an underwater cable may comprise a body having an outer periphery, body being mountable inside the cable with the cable surrounding the outer periphery of the body. The body may include a cutaway portion, a slot, or a dovetail joint. An underwater cable arrangement may comprise an underwater cable and an internal device disposed in the cable with the cable surrounding the device. The underwater cable may include a stress member connected to the internal device by an interference fit or the internal device may include a slot for receiving the stress member. A method of connecting a stress member of an under water cable to an internal device includes forming an interference fit between a region of increased diameter of the stress member and the internal device.
摘要:
Apparatus and method for retrieving instrumented marine cables. The cable-handling apparatus comprises carriers that capture and pull on rigid elements in or on a marine cable to retrieve the cable hand-over-hand onto a deployment vessel. The carriers are spaced apart along an endless path on spacings matching the spacings of the rigid elements in the cable. A take-up mechanism allows manual adjustment of the relative spacings of the carriers to account for tolerances in the spacings of the rigid elements on the cable.
摘要:
A connection system for connecting external devices to specified locations on a marine seismic streamer. Inner collars are clamped to the cable at specified locations along its length. Each inner collar forms a circular race encircling the cable. An outer collar attached to an external device rotatably receives the inner collar and the encircled streamer in its bore to allow the streamer to rotate freely within the outer collar relative to the external device. The outer collar has an inner face bounding and defining the shape of the bore. The inner face is tapered from an intermediate position outward toward front and rear edges of the outer collar to form a bore that is wider at the front and rear edges than at the intermediate position. This flaring out of the bore provides the streamer three degrees of angular freedom to position itself within the bore. Roller bearings, such as ball bearings or pin bearings, retained in recesses in the collar opening onto the inner face at the intermediate position extend into the bore to provide a low-friction bearing surface to the inner race. The ball bearings are retractable against spring pressure to provide the streamer with two degrees of lateral freedom to translate itself within the bore. In a typical connection system, a single external device is connected to the streamer by a pair of associated inner and outer collars.
摘要:
A connection system for connecting external devices to specified locations on a marine seismic streamer. Inner collars are clamped to the cable at specified locations along its length. Each inner collar forms a circular race encircling the cable. A cuff attached to an external device is in the form of a C-shaped cylindrical ring with a circular inner surface. A gap in the ring interrupts the inner surface. A throat is formed in the ring by the gap, which extends the full length of the cuff across the ends of the C. The spacing between the ends of the C across the throat defines the width of the gap. The width of the gap is slightly larger than the diameter of the cable so that the cuff can be slipped over the cable through the throat. The width of the gap is smaller than the diameter of the circular race so that, when the cuff is slid into position on the race, the cuff cannot be removed radially from the race. The inner surface of the cuff rides on the race to allow the cable to rotate inside the cuff. The race can include a circumferential groove for retaining a retractable pin extending from the external device to snap the device in place and a raised circumferential shoulder to further restrain the cuff and attached device from sliding along the cable.