Extrusion preventing device for incorporation into a sealing element and a well tool device comprising a sealing element in which such an extrusion preventing device is incorporated

A well tool device comprising:

• a mandrel device having a longitudinal center axis;
• a sealing device provided radially outside of the mandrel device,
• wherein a sealing element of the sealing device is configured to be brought from a radially retracted state to a radially expanded state, where the sealing element in the radially expanded state is brought into sealing contact with an inner surface of a well,
• wherein the well tool device further comprises an extrusion preventing device incorporated into the sealing element,
• wherein the extrusion preventing device comprises a wire wound with a plurality of turns to form a torus-shaped coiled spring,
• wherein each turn of the torus-shaped coiled spring is canted with a first angle (α1) with respect to a radial direction of a poloidal plane, and
• wherein each turn of the torus-shaped coiled spring is canted with a second angle (α2) with respect to a longitudinal direction of the poloidal plane.

A sealing element for a well tool device, wherein the sealing element comprises:

• a body made of an elastomeric material;
• and
• an extrusion preventing device incorporated into the sealing element,
• wherein the extrusion preventing device comprises a wire wound with a plurality of turns to form a torus-shaped coiled spring,
• wherein each turn of the torus-shaped coiled spring is canted with a first angle (α1) with respect to a radial direction of a poloidal plane, and
• wherein each turn of the torus-shaped coiled spring is canted with a second angle (α2) with respect to a longitudinal direction of the poloidal plane.

A method for manufacturing a sealing element for a well tool device, wherein the method comprises:

• providing a mould shaped as the sealing element;
• inserting an extrusion preventing device comprising a wire wound with a plurality of turns to form a torus-shaped coiled spring into the mould;
• filling molten elastomeric material into the mould, thereby incorporating the torus-shaped coiled spring into the molten elastomeric material;
• curing the elastomeric material;
• and
• retrieving the sealing element from the mould,
• wherein each turn of the torus-shaped coiled spring is canted with a first angle (α1) with respect to a radial direction of a poloidal plane, and
• wherein each turn of the torus-shaped coiled spring is canted with a second angle (α2) with respect to a longitudinal direction of the poloidal plane.