A downhole mud filter (100) comprising a tubular member (1) connectable to the drill string used to prevent debris-laden fluid from entering sensitive BHA tools and components further downhole relative to the mud filter. A tubular member having a sub assembly consisting of a bristle rings (6) and/or rupture (7) to intentionally create a restriction and divert debris-laden fluid around a cylindrical mesh (2) and/or screen surrounded by permanent magnets (3). The openings (9) on the mesh and/or screen allow fluid to pass through while preventing particulates or debris from entering and retaining such debris on the outside of the screen and/or mesh. Magnets (3) arranged around the outer diameter of the screen and/or mesh (2) and along its length captures and retains smaller ferrous debris which the screen and/or mesh cannot filter.

A downhole apparatus for collecting solids fallback in the tubing of an oil producing borehole comprises two or more baskets to collect the solids fall back, each basket partially occupying a portion of the inner cross section of the tubing, leaving a portion of the inner cross section of the tubing having an unrestricted flow path. The baskets when considered in plan view along longitudinal axis of the tubing are distributed such that together they cover substantially the whole area of the tubing while leaving an unobstructed non-straight flowpath around the baskets.

A downhole apparatus for collecting solids fallback in the tubing of an oil producing borehole comprises two or more baskets to collect the solids fall back, each basket partially occupying a portion of the inner cross section of the tubing, leaving a portion of the inner cross section of the tubing having an unrestricted flow path. The baskets when considered in plan view along longitudinal axis of the tubing are distributed such that together they cover substantially the whole area of the tubing while leaving an unobstructed non-straight flowpath around the baskets.

A chemical capsule joint having a chemical capsule filled with a chemical that is to be released into a casing string to which the chemical capsule joint is deployed in a wellbore after an end of the chemical capsule joint if drilled up. The chemical capsule joint allows continuation of cementing operation until an end of the chemical capsule joint is drilled up to release the chemical from the chemical capsule in the chemical capsule joint. The chemical is them freed from the chemical capsule and allowed to leach into production fluids in the casing string to which the chemical capsule joint is deployed in a well bore.

A hollow milling-bit defines a first interior flow passage. A junk catcher sub is connected to the hollow milling-bit and positioned between the hollow milling-bit and the uphole end. A junk recovery tube is connected to the junk catcher sub and positioned between the junk catcher sub and the uphole end. A reverse circulation diverter sub is connected to the junk recovery tube and positioned between the junk recovery tube and the uphole end. The reverse circulation diverter sub includes a ball seat configured to receive a ball. The first recirculation passage fluidically connects the interior flow passage to an outer surface of the tool. The second recirculation passage fluidically connects the interior flow passage to an outer surface of the tool. A catch basket that defines openings is connected to a downhole end of the reverse circulation diverter sub and positioned in the third interior flow passage in-line.

A hollow milling-bit defines a first interior flow passage. A junk catcher sub is connected to the hollow milling-bit and positioned between the hollow milling-bit and the uphole end. A junk recovery tube is connected to the junk catcher sub and positioned between the junk catcher sub and the uphole end. A reverse circulation diverter sub is connected to the junk recovery tube and positioned between the junk recovery tube and the uphole end. The reverse circulation diverter sub includes a ball seat configured to receive a ball. The first recirculation passage fluidically connects the interior flow passage to an outer surface of the tool. The second recirculation passage fluidically connects the interior flow passage to an outer surface of the tool. A catch basket that defines openings is connected to a downhole end of the reverse circulation diverter sub and positioned in the third interior flow passage in-line.

The present invention relates to a downhole wireline machining tool string for increasing an inner diameter of a well tubular metal structure in a well. The downhole wireline machining tool string has a longitudinal axis and comprises a rotatable tool part comprising a machining tool having a first end part, a second end part, a diameter and a circumference, and a stationary tool part comprising a driving unit configured to rotate the rotatable tool part and powered through the wireline. The machining tool comprises a body having an outer face, and the machining tool further comprising a plurality of inserts, each insert having a length along the longitudinal axis, and the inserts projecting from the outer face of the body and being distributed around the circumference. Furthermore, the present invention relates to a machining tool for increasing an inner diameter of a well tubular metal structure in a well or cutting out a piece, e.g. in a downhole valve.

The present invention relates to a downhole wireline machining tool string for increasing an inner diameter of a well tubular metal structure in a well. The downhole wireline machining tool string has a longitudinal axis and comprises a rotatable tool part comprising a machining tool having a first end part, a second end part, a diameter and a circumference, and a stationary tool part comprising a driving unit configured to rotate the rotatable tool part and powered through the wireline. The machining tool comprises a body having an outer face, and the machining tool further comprising a plurality of inserts, each insert having a length along the longitudinal axis, and the inserts projecting from the outer face of the body and being distributed around the circumference. Furthermore, the present invention relates to a machining tool for increasing an inner diameter of a well tubular metal structure in a well or cutting out a piece, e.g. in a downhole valve.

A downhole catcher device comprises a catching mechanism which is configured to be transferable between a first mode and a second mode. The catching mechanism is further configured for passing by a first operation element if the catching mechanism is in the first mode and for catching a second operation element if the catching mechanism is in the second mode. The transfer between the first and the second mode is triggered (or effected) by a downhole tool which is operated by the second operation element.

A downhole catcher device comprises a catching mechanism which is configured to be transferable between a first mode and a second mode. The catching mechanism is further configured for passing by a first operation element if the catching mechanism is in the first mode and for catching a second operation element if the catching mechanism is in the second mode. The transfer between the first and the second mode is triggered (or effected) by a downhole tool which is operated by the second operation element.