Abstract: A chopper mechanism for providing a fiber to a fluid at an oilfield. The chopper mechanism may be employed to process the fiber from an uncut form to a cut form in order to provide a mixture of the fluid and the fiber with flowback inhibiting character. Techniques of employing the chopper mechanism may be utilized at the site of an oilfield for applications such as fracturing, cementing, and drilling. Additionally, the chopper mechanism itself may be made available as a large high capacity chopper assembly, or a smaller handheld chopper gun for slower rate fiber supply operations.

Abstract: The invention discloses a cement slurry composition for cementing a well comprising: an hydraulic cement, water and a combination made of a cellulosic polymer and an acrylamido-methyl-propane sulfonate co- or ter-polymer, wherein the density of said cement slurry is above 1700 kg/m3.

Abstract: Wellbore strengthening during drilling may be achieved by including chemicals in the drilling fluid that can be polymerised when exposed to microwave energy. Selected chemicals are mixed with the drilling fluid but do not react with it. The chemicals concentrate in a filter cake on the borehole wall during drilling-fluid circulation. A tool, which comprises a microwave source, is used to trigger polymerisation or crosslinking reactions within the filter cake. The polymerisation or crosslinking reactions cause the formation of a film or gel that strengthens the wellbore.

Abstract: A multiple activation-device launching system for a cementing head comprises a launcher body and at least one launching chamber that are sized to receive one or more activation devices therein. The activation devices are launched into the principal process-fluid stream inside the cementing head, and may be darts, balls, bombs, canisters and combinations thereof. The launching chambers are in fluid communication with an external power source for launching the activation device into the principal process-fluid stream.

Abstract: Apparatus and method for determining pressure in a well is provided. A sensor for determining the rate of change of pressure in a well comprises: a first cavity body defining an enclosed volume, a portion of one wall of the cavity body being constituted by a pressure sensitive membrane capable of exposure to the well pressure so as to be responsive thereto; and a first capillary connected to the first cavity body at one end and being open to the well pressure at the other end so as to provide pressure communication between the well pressure and the interior of the first cavity body; wherein a length of the first capillary, an internal diameter of the first capillary, and the volume of the first cavity body are such that the sensor has a predetermined pressure response that comprises an input minus a low-pass filtered version of the input, and a predetermined time constant.

Abstract: An apparatus and method for determining the phase fraction of a fluid collected downhole is shown comprising an x-ray generator, a filter, a sample cell, and a radiation detector. The filter produces a radiation spectrum with a high energy portion and a low energy portion. Filtered radiation is passed through a sample fluid and the resulting attenuated radiation signal is used in calculating the phase fractions of oil, water, and gas in the sample fluid. In one embodiment, a second reference radiation detector measures the radiation directly from the x-ray generator and this measurement is used in normalizing the fraction result. The ratio of the high energy signal to low energy signal of the reference detector is used in controlling the input voltage of the x-ray generator thus ensuring a stable spectrum.

Abstract: A well for producing oil from an underground formation, comprises a vertical section extending from the surface to a depth below the oil-producing formation; a sidetrack or perforated interval (production zone) extending from the vertical section into the oil-producing formation; and a valve, located in the well, and operable to prevent flow of fluid from the vertical section into the production zone and a valve to prevent flow of fluid from the portion below the production zone into the production zone or into the vertical section above the production zone.