A downhole tool and method therefor use a deviated flow path to prevent/mitigate fallback of solids during shutdown of an ESP. The deviated flow path leverages the direction of fallback downhole and the relative inertias of the solid particulates and the fluid to minimize fallback into the ESP. The particulates change flow direction more slowly than fluid, and thus largely avoid the deviated flow path to instead fall through a bypass path during fallback. This obviates the need for mechanical valves that may be subject to excessive mechanical wear or other issues associated with solid particulates.

The present invention relates to an annular barrier to be expanded in an annulus between a well tubular metal structure and an inside wall of a borehole downhole for providing zone isolation between a first zone and a second zone of the borehole, comprising a tubular metal part for mounting as part of the well tubular metal structure, an expandable metal sleeve surrounding the tubular metal part, each end of the expandable metal sleeve being connected with the tubular metal part, an expandable space between the expandable metal sleeve and the tubular metal part, and an expansion opening in the tubular metal part through which fluid enters in order to expand the expandable metal sleeve, wherein the annular barrier further comprises a pressure-intensifying unit. The invention also relates to a downhole system comprising a well tubular metal structure and an annular barrier.

The present invention relates to an annular barrier to be expanded in an annulus between a well tubular metal structure and an inside wall of a borehole downhole for providing zone isolation between a first zone and a second zone of the borehole, comprising a tubular metal part for mounting as part of the well tubular metal structure, an expandable metal sleeve surrounding the tubular metal part, each end of the expandable metal sleeve being connected with the tubular metal part, an expandable space between the expandable metal sleeve and the tubular metal part, and an expansion opening in the tubular metal part through which fluid enters in order to expand the expandable metal sleeve, wherein the annular barrier further comprises a pressure-intensifying unit. The invention also relates to a downhole system comprising a well tubular metal structure and an annular barrier.

A backup ring for a seal assembly including a body having a radially outer surface and a radially inner surface, an opening in the body extending from the radially outer surface toward the radially inner surface, the opening being receptive to a line to guide and protect the line. A wellbore system including a borehole in a subsurface formation, a string disposed in the borehole, a seal system disposed in the string, the system including a backup ring comprising a body having a radially outer surface and a radially inner surface and an opening in the body extending from the radially outer surface toward the radially inner surface, the opening being receptive to a line to guide and protect the line and a method for running a line along a seal system.

A downhole tool for cleaning and sealing a wellbore includes a wash tool configured at a downhole end of the downhole tool to generate pulses of a first fluid at a first frequency and a first pressure for washing a target interval of a wellbore. The downhole tool further includes a plugging tool configured uphole or downhole from the wash tool to generate pulses of a second fluid at a second frequency and a second pressure for depositing a sealing plug at the target interval of the wellbore. The second fluid has a higher viscosity than the first fluid, the second frequency is lower than the first frequency, and the second pressure is higher than the first pressure.

A downhole tool for cleaning and sealing a wellbore includes a wash tool configured at a downhole end of the downhole tool to generate pulses of a first fluid at a first frequency and a first pressure for washing a target interval of a wellbore. The downhole tool further includes a plugging tool configured uphole or downhole from the wash tool to generate pulses of a second fluid at a second frequency and a second pressure for depositing a sealing plug at the target interval of the wellbore. The second fluid has a higher viscosity than the first fluid, the second frequency is lower than the first frequency, and the second pressure is higher than the first pressure.

A method for the fracking or stimulation of a hydrocarbon-bearing formation, said method comprising the steps of: providing a wellbore in need of stimulation; inserting a plug in the wellbore at a predetermined location; inserting a perforating tool and a spearhead or breakdown acid into the wellbore; positioning the tool at said predetermined location; perforating the wellbore with the tool thereby creating a perforated area; allowing the spearhead acid to come into contact with the perforated area for a predetermined period of time sufficient to prepare the formation for fracking or stimulation; removing the tool from the wellbore; and initiating the fracking of the perforated area using a fracking fluid. Also disclosed is a corrosion inhibiting composition for use with the acid composition.

The disclosed embodiments include methods to monitor expansion of a metallic sealant deployed in a wellbore, methods to monitor downhole fluid displacement, and downhole metallic sealant measurement systems. The method to monitor expansion of a downhole metallic sealant includes deploying a metallic sealant deployed along a section of a wellbore. The method also includes exposing the metallic sealant to a reacting fluid to initiate a galvanic reaction. The method further includes measuring a change in temperature caused by the galvanic reaction. The method further includes determining an amount of expansion of the metallic sealant based on the change in the temperature.

A cementing tool and a method for cementing a casing string using the cementing tool is provided. The cementing tool comprises threaded top and bottom openings for attaching to a casing string, a plurality of ports, and a plurality of shear plugs shaped to fit within the ports. In the method, a casing string comprising the cementing tool is run into a well and the cementing process of the casing string is initiated. When the casing shoe of the casing string becomes plugged, the cementing tool is activated without removing the casing string from the well. Activation of the cementing tool releases pressure trapped in the cementing tool, thereby releasing the shear plugs from the ports and opening the ports to create alternative passages for the cement to complete the cementing process.

An engineered composite system designed to be passive or inert under one set of conditions, but becomes active when exposed to a second set of conditions. This system can include a dissolving or disintegrating core, and a surface coating that has higher strength or which only dissolves under certain temperature and pH conditions, or in selected fluids. These reactive materials are useful for oil and gas completions and well stimulation processes, enhanced oil and gas recovery operations, as well as in defensive and mining applications requiring high energy density and good mechanical properties, but which can be stored and used for long periods of time without degradation.