Chevron seal for a well tool

A seal member for use in a sealing apparatus which is used in a wellbore tool to sealingly engage a moveable surface of a noncontinuously mating moveable member to prevent a flow of a wellbore fluid along said moveable surface of said noncontinuously mating moveable member, said seal member comprising:

• a dynamic engagement wing defining a portion of said seal member which is disposed to engage said noncontinuously mating moveable member, said dynamic engagement wing at least in part defined by:
• an active end surface which faces said flow of said wellbore fluid;
• a passive end surface which is oppositely disposed across said outer wing from said active end surface;
• a dynamic engagement wing surface which includes a sealing surface which sealingly engages said noncontinuously mating moveable member;
• wherein said active end surface which faces said flow of said wellbore fluid at least in part being defined by:
• an inwardly protruding surface which is shaped to provide a sealing energization so that when said inwardly protruding surface is pressed by said wellbore fluid said sealing surface is pushed into sealing engagement with said moveable surface of said noncontinuously mating moveable member;
• and
• a blunt wing surface which is disposed intermediate of said active end surface and said dynamic engagement wing surface, and which is sized to provide a balance in a rigidity of said dynamic engagement wing which is stiff to prevent displacement of said dynamic engagement wing into a path of said moveable surface of said noncontinuously mating moveable member, and flexible to allow said sealing energization of said wellbore fluid pushing said sealing surface into sealing engagement.

A seal assembly for use in a wellbore to sealingly engage a moveable surface in a noncontinuously mating engagement in which said moveable surface includes an edge which is moved across said seal assembly, said seal assembly comprising:

• a thermoplastic seal member having a wing portion extending therefrom for sealingly engaging said moveable surface to prevent a fluid flow therebetween;
• a means for pressing said thermoplastic seal member into sealingly engaging said moveable surface to prevent said fluid flow therebetween;
• a retainer means for supporting said thermoplastic seal member against said means for pressing;
• and
• said wing portion of said thermoplastic seal member having an end thickness for providing sufficient rigidity to prevent said means for pressing from urging said wing portion substantially into a path of said edge of said moveable member, and thus preventing said edge from damaging said thermoplastic seal member.

A thermoplastic seal assembly for sealingly engaging a surface having an edge which said thermoplastic seal assembly moves across while urged to sealingly engage said surface, said thermoplastic seal assembly comprising:

• a thermoplastic seal member having a wing portion extending therefrom for sealingly engaging said moveable surface to prevent a fluid flow therethrough;
• a means for pressing said thermoplastic seal member into said surface for sealingly engaging said surface to prevent said fluid flow therethrough;
• a pair of thermoplastic retainer members, with at least one of said pair of retainer members disposed on each of two opposing sides of said thermoplastic seal member for holding an initial shape of said thermoplastic seal member against said means for pressing;
• and
• wherein said thermoplastic seal member, disposed between said pair of thermoplastic retainer members, includes an end thickness for preventing said means for pressing from urging said thermoplastic seal member substantially beyond said edge of said surface to prevent damage to said thermoplastic seal member when passing across said edge.

A sealing assembly for use in a wellbore tool to seal an annular space between a first and second surfaces to prevent a wellbore fluid flow therethrough, wherein said first and second surfaces are concentrically disposed and each have a generally cylindrical shape and are axially moveable with respect to each other in a noncontinuously mating engagement, said sealing assembly comprising:

• at least one thermoplastic seal ring formed from a thermoplastic material which is pliable at a high wellbore temperature, said at least one thermoplastic seal ring sealingly engaging between said first and second surfaces for preventing said wellbore fluid flow through said annular space at a temperature lower than said high wellbore temperature, said at least one thermoplastic seal ring being formed in a shape with a cross-section including opposing sides of a generally inwardly protruding shape and a generally outwardly protruding shape;
• a plurality of retainer seal rings formed from a high temperature thermoplastic material, said plurality of retainer seal rings sealingly engaging between said first and second members for preventing both said wellbore fluid flow though said annular space and extrusion of said at least one thermoplastic seal ring at said high temperature, said plurality of retainer seal rings formed in a shape with said cross-section including opposing sides of said generally inwardly protruding shape and said generally outwardly protruding shape, wherein said generally outwardly protruding shape has a mating engagement with said generally inwardly protruding shape, with said mating engagement having an interference fit wherein said generally outwardly protruding shape when forcibly in said mating engagement with said generally inwardly protruding shape will urge an expansion of said generally inwardly protruding shape;
• wherein said at least one thermoplastic seal ring and said plurality of retainer seal rings are secured to said first member for sealingly engaging said second member and moving past an edge of said second member;
• and
• wherein one of said plurality of retainer seal rings is disposed adjacent to and in said mating engagement with each axial end of each of said at least one thermoplastic seal ring for retaining said shape of said at least one thermoplastic seal ring at said high wellbore temperatures so that said at least one thermoplastic seal ring will, upon cooling to said temperature lower than said high wellbore temperature, sealingly engage between said first and second surfaces for preventing said wellbore fluid flow.