Abstract: Tubular ends are heated to a predetermined temperature above 1200 degrees Celsius and surrounded by a shield gas when the tubular ends are pressed together to form forge welded tubular ends. The forge welded tubular ends are then cooled down rapidly from said temperature above 1200 to at most 600 degrees Celsius within 3 minutes after the forge welding operation.

Abstract: A method is provided of in-situ casting well equipment wherein a metal is used which expands upon solidification. A body of such metal is placed in a cavity in a well. Before or after placing the metal in the cavity in the well, the body is brought at a temperature above the melting point of the metal. The metal of the body in the cavity is solidified by cooling it down to below the melting point of the metal.

Abstract: An improved method of permanently marking the location of a tubular joint, the method including creating a cavity into the end surface of one of the tubular ends that are to be joined by a forge weld or screw thread connection, inserting a marker into said cavity and subsequently joining the tubular ends.

Abstract: A method of joining tubulars includes the step of joining the tubulars by forge welding. The tubular ends that are to be welded together may be shaped into a sloping configuration, such that when the tubular ends are heated during the forge welding process the heated tubular ends deform as a result of thermal expansion into a substantially longitudinally oriented cylindrical shape.

Abstract: An automated method for forge welding tubulars including heating the tubular ends to be joined in a welding chamber while the heated tubular ends are maintained aligned and parallel relative to each other and at a small spacing, whereupon the heated tubular ends are pressed together while a reducing shield gas is injected into the chamber.

Abstract: Tubular ends are heated to a predetermined temperature above 1200 degrees Celsius and surrounded by a shield gas when the tubular ends are pressed together to form forge welded tubular ends. The forge welded tubular ends are then cooled down rapidly from said temperature above 1200 to at most 600 degrees Celsius within 3 minutes after the forge welding operation.

Abstract: A method is provided of in-situ casting well equipment wherein a metal is used which expands upon solidification. A body of such metal is placed in a cavity in a well. Before or after placing the metal in the cavity in the well, the body is brought at a temperature above the melting point of the metal. The metal of the body in the cavity is solidified by cooling it down to below the melting point of the metal.

Abstract: A method for interconnecting tubulars by forge welding involves arranging the tubular ends that are to be interconnected at a distance, up to a few millimeters from each other in a shield gas chamber, into which a reducing non-explosive flushing fluid mixture (e.g. N2+H2) is injected; heating each tubular end within the space by means of at least three electrodes that are pressed at circumferentially spaced intervals against the wall of each tubular, adjacent to the tubular end such that a high frequency electrical current is transmitted in a substantially circumferential direction through the tubular segments between the electrodes; and moving the thus uniformly heated tubular ends towards each other until a forge weld is formed between the heated tubular ends.

Abstract: A method of joining expandable tubulars includes joining the tubulars by forge welding and flushing a reducing flushing gas around the heated tubular ends during at least part of the forge welding operation such that oxides are removed from the forge welded tubular ends and the amount of irregularities between the forge welded tubular ends is limited.

Abstract: A method is provided of in-situ casting well equipment wherein a metal is used which expands upon solidification. A body of such metal is placed in a cavity in a well. Before or after placing the metal in the cavity in the well, the body is brought at a temperature above the melting point of the metal. The metal of the body in the cavity is solidified by cooling it down to below the melting point of the metal.

Abstract: A method of joining heavy duty oilfield, well, or other tubulars includes the step of joining the tubulars by forge welding and flushing a reducing flushing gas around the heated tubular ends during at least part of the forge welding operation such that oxides are removed from the forge welded tubular ends and the amount of oxide inclusions and irregularities between the forge welded tubular ends is limited. The tubular ends may have a teethed sinusoidal or other non-planar shape to inhibit any abrupt variations of the wall strength in the welding area and/or to reduce shear forces to the forge weld when the tubulars are twisted and/or radially expanded.

Abstract: An improved method of permanently marking the location of a tubular joint, the method including creating a cavity into the end surface of one of the tubular ends that are to be joined by a forge weld or screw thread connection, inserting a marker into said cavity and subsequently joining the tubular ends.

Abstract: The invention relates to a method for forge welding tubulars such that formation of upsets in the welding zone is minimized which involves shaping the tubular ends that are to be welded together into an inwardly sloping configuration such that when the tubular ends are heated during the forge welding process the heated tubular ends deform as a result of thermal expansion into a substantially longitudinally oriented cylindrical shape.

Abstract: A method for inspecting welds between welded tubular ends includes arranging a series electromagnetic acoustic transducer (EMAT) assemblies in circumferential direction adjacent to an inner and/or outer surface of at least one of the welded tubular ends and inducing the EMAT assemblies to transmit sequentially or simultaneously acoustic shear wave signals towards the weld and to detect the shear waves reflected by and/or passing through the weld while the EMAT assemblies are maintained in a substantially fixed position relative to the weld such that at least a substantial part of the weld is scanned by the EMAT assemblies instantly after the weld is made.

Abstract: A method for interconnecting tubulars by forge welding involves arranging the tubular ends that are to be interconnected at a distance, up to a few millimeters from each other in a shield gas chamber, into which a reducing non-explosive flushing fluid mixture (e.g. N2+H2) is injected; heating each tubular end within the space by means of at least three electrodes that are pressed at circumferentially spaced intervals against the wall of each tubular, adjacent to the tubular end such that a high frequency electrical current is transmitted in a substantially circumferential direction through the tubular segments between the electrodes; and moving the thus uniformly heated tubular ends towards each other until a forge weld is formed between the heated tubular ends.

Abstract: A method of joining expandable tubulars includes joining the tubulars by forge welding and flushing a reducing flushing gas around the heated tubular ends during at least part of the forge welding operation such that oxides are removed from the forge welded tubular ends and the amount of irregularities between the forge welded tubular ends is limited.

Abstract: An automated method for forge welding tubulars including heating the tubular ends to be joined in a welding chamber while the heated tubular ends are maintained aligned and parallel relative to each other and at a small spacing, whereupon the heated tubular ends are pressed together while a reducing shield gas is injected into the chamber.

Abstract: A method is provided of in-situ casting well equipment wherein a metal is used which expands upon solidification, the method comprising the steps of: placing a body of said metal in a cavity in the well; bringing said body at a temperature above the melting point of the metal; cooling down said body to below the melting point of the metal, thereby solidifying the metal of said body in the cavity.

Abstract: A method for inspecting welds between welded tubular ends includes arranging a series electromagnetic acoustic transducer (EMAT) assemblies in circumferential direction adjacent to an inner and/or outer surface of at least one of the welded tubular ends and inducing the EMAT assemblies to transmit sequentially or simultaneously acoustic shear wave signals towards the weld and to detect the shear waves reflected by and/or passing through the weld while the EMAT assemblies are maintained in a substantially fixed position relative to the weld such that at least a substantial part of the weld is scanned by the EMAT assemblies instantly after the weld is made.