Methods and apparatus are disclosed. The apparatus includes a substantially cylindrical mount body (350) comprising a first open mouth at a first end of the cylindrical body (350) and a further open mouth at a remaining end of the cylindrical body, a substantially cylindrical inner surface, and an outer surface that includes a plurality of spaced apart substantially parallel recessed regions that extends circumferentially around the body, wherein the cylindrical body (350) is tapered at each end and at least one securing element is located between the recessed regions.

Methods and apparatus are disclosed. The apparatus includes a substantially cylindrical mount body (350) comprising a first open mouth at a first end of the cylindrical body (350) and a further open mouth at a remaining end of the cylindrical body, a substantially cylindrical inner surface, and an outer surface that includes a plurality of spaced apart substantially parallel recessed regions that extends circumferentially around the body, wherein the cylindrical body (350) is tapered at each end and at least one securing element is located between the recessed regions.

Spiral forming methods can be used to join edges of a rolled material along a spiral joint to form conical and/or cylindrical structures. Alignment of the edges of the rolled material can be controlled in a wrapping direction as the material is being joined along the spiral joint to form the structure. By controlling alignment of the edges of the material as the edges of the material are being joined, small corrections can be made over the course of forming the structure facilitating control over geometric tolerances of the resulting spiral formed structure.

Spiral forming methods can be used to join edges of a rolled material along a spiral joint to form conical and/or cylindrical structures. Alignment of the edges of the rolled material can be controlled in a wrapping direction as the material is being joined along the spiral joint to form the structure. By controlling alignment of the edges of the material as the edges of the material are being joined, small corrections can be made over the course of forming the structure facilitating control over geometric tolerances of the resulting spiral formed structure.

A method for producing a drill shaft for a wet drill bit includes forming N, where N≥1, strip materials into a tubular body where the tubular body is integrally joined at strip edges of the strip materials by N connection welds. At least one strip material of the strip materials is provided with at least one recess before the integral joining of the strip edges.

A flexible pipe body and a method of providing electrical continuity are disclosed. The flexible pipe body comprises a first armour layer formed from a helical winding of a metal tape element, a further armour layer formed from a helical winding of a further metal tape element, and at least one intermediate layer between the first and further armour layers, said intermediate layer comprising a helically wound electrically insulating tape element (800.sub.0, 800.sub.1, 800.sub.2, 800.sub.3, 800.sub.4) and a helically wound electrically conductive tape element (810.sub.0, 810.sub.1, 810.sub.2, 810.sub.3, 810.sub.4).

Feeding stock used to form a tapered structure into a curving device such that each point on the stock undergoes rotational motion about a peak location of the tapered structure; and the stock meets a predecessor portion of stock along one or more adjacent edges.

Disclosed is a tubular core on which sheets of metal or other material can be wound and supported, for shipment, handling and dispersal, and a method for forming the core. The core comprises a metal sheet or strip which has a rectangular-ribbed cross-sectional profile comprising rectangular, flat ribs, and which is wound spirally into a tubular configuration. The core is formed by passing the strip through a plurality of roll-forming stands, to progressively form sections of the ribs and progressively define the sections into the rectangular ribbed profile in which the flat ribs collectively form a support surface for the sheets which are to be wound on the core.

Spiral forming methods can be used to join edges of a rolled material along a spiral joint to form conical and/or cylindrical structures. Alignment of the edges of the rolled material can be controlled in a wrapping direction as the material is being joined along the spiral joint to form the structure. By controlling alignment of the edges of the material as the edges of the material are being joined, small corrections can be made over the course of forming the structure facilitating control over geometric tolerances of the resulting spiral formed structure.

Spiral forming methods can be used to join edges of a rolled material along a spiral joint to form conical and/or cylindrical structures. Alignment of the edges of the rolled material can be controlled in a wrapping direction as the material is being joined along the spiral joint to form the structure. By controlling alignment of the edges of the material as the edges of the material are being joined, small corrections can be made over the course of forming the structure facilitating control over geometric tolerances of the resulting spiral formed structure.