Loading patent…
AssigneeShell Oil Company
InventorsDaniele Di Crescenzo, Mark Michael Shuster, Djurre Hans Zijsling, Rob Bosman
Estimating the term…
A tubular member (1) with a relative rough (1.5-10 μm) inner surface (5) coated solid lubricating film (10) which is transformed into a substantially viscous rubbery viscoelasto-plastic phase at temperatures in a range between 50° C. and 110° C. is expanded by moving an expansion member (24) with a relatively smooth outer surface (roughness<1.5 μm) therethrough, such that during expansion a viscous viscoelastoplastic substantially rubbery lubricating film (44) is generated between the tubular member (1) and the expansion mandrel (24), which film remains bonded to the rough inner surface (5) of the expanded tubular (1), but does not stick to the relatively hot and smooth expansion member (24).
A method of expanding a tubular member, comprising:
The method according to 1, wherein the first surface roughness and the surface roughness of the expansion member are each less than or equal to 1 μm and greater than zero μm.
The method according to 1, wherein the step of treating a contact part of the inner surface to increase the surface roughness from a first surface roughness to a second surface roughness comprises blasting the contact part with particles.
An expandable tubular having a longitudinal passage and having an inner surface, wherein a contact part of the inner surface is treated such that an initial surface roughness of the contact part of the inner surface is increased to a second surface roughness between 1.5 μm and 10 μm, and wherein the contact part of the inner surface is covered by a lubricating coating, which is configured to be in a viscoelastoplastic phase at temperatures in a range between 50° C. and 110° C., wherein the second surface roughness is reduced to a third surface roughness during expanding of the longitudinal passage.
Dependencies are inferred from the claim text.