Spring energized seal assemblies each with one or two sealing elements and a canted coil spring located in a spring cavity of the sealing element or of the two sealing elements to bias an inner flange and an outer flange of the respective spring cavity away from one another. The canted coil springs can have un-conventional coil shapes with one or more straight coil segments and/or with curved connecting ends. The coils can have dimples to provide multiple biasing points. The coils can have loops. The canted coil springs with un-conventional coil shapes can be used to improve spring loading on a sealing element.

A canted coil spring includes a core wire 10 formed of steel having a pearlite structure; and a copper plating layer 20 formed of copper or a copper alloy and covering an outer circumferential surface 11 of the core wire 10. The steel contains 0.5 mass % or more and 1.0 mass % or less carbon, 0.1 mass % or more and 2.5 mass % or less silicon, and 0.3 mass % or more and 0.9 mass % or less manganese, with the balance being iron and inevitable impurities. The copper plating layer 20 has a crystallite size of 220±50 Å.

A shock absorbing device having at least one canted spring disposed between two members is described. When the members move toward each other, the one or more canted coil springs are canted and compressed. The shock absorbing device takes advantage of the unique force-displacement curve of canted springs and reduces bounce back.

Canted coil spring rings each with a first plurality of coils having first coil major and minor axes; a second plurality of coils each having second coil major and minor axes; the coils of the first plurality of coils alternating with the coils of the second plurality of coils according to an alternating pattern. The spring rings having inner and outer perimeters and wherein the inner perimeter of the spring ring is defined by at least said first plurality of coils. The resulting configuration of the spring ring has improved spacing along the inner perimeter, among others, with respect to a similar canted coil spring ring having a constant coil cross section, such as a coil length with all similar coils.

Spring energized seal assemblies each with one or two sealing elements and a canted coil spring located in a spring cavity of the sealing element or of the two sealing elements to bias an inner flange and an outer flange of the respective spring cavity away from one another. The canted coil springs can have un-conventional coil shapes with one or more straight coil segments and/or with curved connecting ends. The coils can have dimples to provide multiple biasing points. The coils can have loops. The canted coil springs with un-conventional coil shapes can be used to improve spring loading on a sealing element.

A copper-coated steel wire includes a core wire made of a stainless steel, and a coating layer made of copper or a copper alloy and covering an outer peripheral surface of the core wire. In a cross section perpendicular to a longitudinal direction of the core wire, the outer peripheral surface of the core wire has a value of an arithmetic mean roughness Ra of not less than 25% and not more than 90% of a thickness of the coating layer.

A spring assembly with two or more springs, one inside another. The spring assembly can have two springs wherein one spring is located inside another spring, and the outer spring can be a helical ribbon spring and the inner spring can be a canted coil spring to provide support to the outer helical ribbon spring. Support is provided where the helical ribbon spring may have some limitations that the inner spring is able to overcome. Limitations of the helical ribbon spring may be a limited force versus deflection curve which the additional spring support of the secondary spring may overcome.

A wire material for a canted coil spring includes a core wire composed of a steel having a pearlite structure, a copper plating layer covering the outer peripheral surface of the core wire, the copper plating layer being composed of copper or a copper alloy, and a hard layer disposed adjacent to the outer periphery of the copper plating layer, the hard layer having a higher hardness than the copper plating layer. The steel constituting the core wire contains 0.5% or more by mass and 1.0% or less by mass carbon, 0.1% or more by mass and 2.5% or less by mass silicon, and 0.3% or more by mass and 0.9% or less by mass manganese, the balance being iron and unavoidable impurities.

An extrusion preventing device for incorporation into a sealing element of a well tool device includes a wire wound with a plurality of turns to form a torus-shaped coiled spring. Each turn of the torus-shaped coiled spring is canted. A method for manufacturing a sealing element for a well tool device includes providing a mould shaped as the sealing element; inserting an extrusion preventing device including 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.

A copper-coated steel wire includes: a core wire made of steel having a pearlite structure; and a coating layer covering a surface of the core wire and made of Cu or a Cu alloy. The steel contains C by greater than or equal to 0.5% by mass and less than or equal to 1.0% by mass, Si by greater than or equal to 0.1% by mass and less than or equal to 2.5% by mass, Mn by greater than or equal to 0.3% by mass and less than or equal to 0.9% by mass, and the balance consisting of Fe and inevitable impurities. In a cross section perpendicular to a longitudinal direction, a value of surface roughness Ra of the core wire is greater than or equal to 25% and less than or equal to 70% of a thickness of the coating layer.