A drilling assembly comprises a drill bit and a cutting assembly. The drilling assembly forms a longitudinal center axis. The drill bit and cutting assembly fastened to a rotatable spline drive assembly. The cutting assembly being resiliently displaceable to the drill bit along the center axis such that in a first position the drill bit is surrounded by the cutting assembly and in a second position a free end portion of the drill bit projects beyond the cutting assembly along the center axis. The cutting assembly comprises an endmill which comprises a central through hole which is complementary to the outer diameter of the drill bit. A method for cutting swarfs created by drilling with the endmill is described.

A drilling assembly comprises a drill bit and a cutting assembly. The drilling assembly forms a longitudinal center axis. The drill bit and cutting assembly fastened to a rotatable spline drive assembly. The cutting assembly being resiliently displaceable to the drill bit along the center axis such that in a first position the drill bit is surrounded by the cutting assembly and in a second position a free end portion of the drill bit projects beyond the cutting assembly along the center axis. The cutting assembly comprises an endmill which comprises a central through hole which is complementary to the outer diameter of the drill bit. A method for cutting swarfs created by drilling with the endmill is described.

Provided is a mill bit and well system. The mill bit, in one aspect, includes a tubular having an uphole end and a downhole end. The mill bit, in accordance with this aspect, further includes a first cutting section having one or more first cutting surfaces disposed about the tubular, the first cutting section having a first material removal rate and configured to engage with wellbore casing disposed within a wellbore. The mill bit, in accordance with this disclosure, further includes a second cutting section having one or more second cutting surfaces disposed about the tubular, the second cutting section having a second material removal rate less than the first material removal rate and configured to engage with a whipstock disposed within the wellbore.

A reamer includes a housing, a first reamer block, and a second reamer block. The first reamer block includes a leading wall. A second reamer block includes a trailing wall, the trailing wall including a recess. The leading wall is inserted into or nested in the recess to increase the coverage-to-exposure ratio.

The present invention relates to a downhole tool for removing a restriction in a well tubular metal structure having a wall and an inner diameter, the restriction partly blocking the inner diameter, creating an opening defined at least partly by a rim section of the restriction, the downhole tool having a tool axis and comprising a tool body having a first part and a second part, an electrical motor arranged in the first part for rotating a rotatable shaft, a core bit arranged in the second part and having a first end connected with the rotatable shaft and a second end having a cutting edge, wherein the second part of the downhole tool further comprises a locator for locating the rim section, a collecting means for collecting part of the restriction to be cut out by the cutting edge, the locator and the collecting means are rotating with the core bit until the locator locates the rim section and a threshold value is reached.

The present invention relates to a downhole tool for removing a restriction in a well tubular metal structure having a wall and an inner diameter, the restriction partly blocking the inner diameter, creating an opening defined at least partly by a rim section of the restriction, the downhole tool having a tool axis and comprising a tool body having a first part and a second part, an electrical motor arranged in the first part for rotating a rotatable shaft, a core bit arranged in the second part and having a first end connected with the rotatable shaft and a second end having a cutting edge, wherein the second part of the downhole tool further comprises a locator for locating the rim section, a collecting means for collecting part of the restriction to be cut out by the cutting edge, the locator and the collecting means are rotating with the core bit until the locator locates the rim section and a threshold value is reached.

A cutting element has a cutting face with a geometry including at least one protrusion spaced a radial distance apart from an edge of the cutting element, the edge extending around an entire periphery of the cutting face, and a lower portion extending within the distance between the at least one protrusion and the edge, wherein a lower portion axial height measured between the edge and a base of the at least one protrusion is less than 30 percent of a greatest axial height of the at least one protrusion measured between the base of the at least one protrusion and an axially highest point of the at least one protrusion.

In a drill bit which has hard-faced cutting or gauge protection elements positioned to be in direct contact with subterranean formation as the bit is rotated, at least one of these elements includes a window positioned to be in direct contact with the formation or cuttings from the formation as the bit rotates and moves forward to drill into the formation. Electromagnetic radiation with wavelength in the range from 100 nm to 2600 nm is transmitted through the window to the formation in contact with the window. Electromagnetic radiation such as fluorescence that returns through the same window is received by a spectrometer. The source and receiver of electromagnetic radiation are both accommodated within the downhole drilling equipment but spaced from the windowed element. The electromagnetic radiation travels along light guides from the source to the window and from the window to the receiver.

In a drill bit which has hard-faced cutting or gauge protection elements positioned to be in direct contact with subterranean formation as the bit is rotated, at least one of these elements includes a window positioned to be in direct contact with the formation or cuttings from the formation as the bit rotates and moves forward to drill into the formation. Electromagnetic radiation with wavelength in the range from 100 nm to 2600 nm is transmitted through the window to the formation in contact with the window. Electromagnetic radiation such as fluorescence that returns through the same window is received by a spectrometer. The source and receiver of electromagnetic radiation are both accommodated within the downhole drilling equipment but spaced from the windowed element. The electromagnetic radiation travels along light guides from the source to the window and from the window to the receiver.

A drill bit for drilling a bore, the drill bit comprising: an outer housing; a primary cutting structure defining a cutting plane of a first diameter; a flow path arranged to let drilling fluid flow through the drill bit; and a deployable blade assembly at least partially located within the outer housing, the deployable blade assembly comprising a cutting structure and being arranged to be axially movable from a first position, in which the deployable cutting structure is recessed with respect to the primary cutting structure, towards the cutting plane, to a second position; wherein when the deployable blade assembly is in the second position, the deployable cutting structure defines a cutting diameter which is less than or equal to the first diameter.