Pipe sealing joint, closure ring for such a joint and application of said joint in particular to hydrocarbon-conveying pipes

Claim 2

A pipe sealing joint comprising a male end of a first pipe and a socket of a second pipe, the second pipe having a body portion axially adjacent to and rigid with the socket and the socket defining a cavity which is coaxial with the male end and defines with the male end an aNnular space and includes a substantially cylindrical surface, a sealing element having at least one portion which is disposed in the cavity and is in direct radial contact with the male end and the socket and in radially compressed condition between the male end and the socket, and means for partitioning off the sealing element from the interior of the pipes and thereby protecting the sealing element from the substance conveyed in the pipes and comprising a protective ring of flexible material placed in the cavity at an end of the cavity adjacent the body portion, and a closure ring which is of a material resisting corrosion by said substance and is disposed in the cavity between the sealing element and the protective ring, the closure ring extending radially across substantially the whole of said annular space and comprising a circumferentially continuous annular outer lip portion which has substantially the shape of a cylinder and bears against said cylindrical surface.

Claim 3

A pipe sealing joint comprising a male end of a first pipe and a socket of a second pipe, the second pipe having a body portion axially adjacent to and rigid with the socket and the socket defining a cavity which is coaxial with the male end and defines with the male end an annular space and includes a substantially cylindrical surface, a sealing element having at least one portion which is disposed in the cavity and is in direct radial contact with the male end and the socket and in radially compressed condition between the male end and the socket, and means for partitioning off the sealing element from the interior of the pipes and thereby protecting the sealing element from the substance conveyed in the pipes and comprising a protective ring of flexible material placed in the cavity at an end of the cavity adjacent the body portion, and a closure ring which is of a material resisting corrosion by said substance and is disposed in the cavity between the sealing element and the protective ring, the closure ring extending radially across substantially the whole of said annular space and comprising an L-shaped portion in axial section which defines an outer circumferentially continuous annular lip portion having a substantially cylindrical general shape and bearing against said cylindrical surface of the cavity of the socket between the sealing element and the protective ring and an annular web portion which adjoins said lip portion and is transverse with respect to the axis of the pipes.

Claim 4

A pipe sealing joint comprising a male end of a first pipe and a socket of a second pipe, the second pipe having a body portion axially adjacent to and rigid with the socket and the socket defining a cavity which is coaxial with the male end and defines with the male end an annular space and includes a substantially cylindrical surface, a sealing element having at least one portion which is disposed in the cavity and is in direct radial contact with the male end and the socket and in radially compressed condition between the male end and the socket, and means for partitioning off the sealing element from the interior of the pipes and thereby protecting the sealing element from the substance conveyed in the pipes and comprising a protective ring of flexible material placed in the cavity at an end of the cavity adjacent the body portion, and a closure ring which is of a material resisting corrosion by said substance and is disposed in the cavity between the sealing element and the protective ring, the closure ring extending radially across substantially the whole of said annular space and comprising an L-shaped portion in axial section which defines an outer circumferentially continuous annular lip portion having a substantially cylindrical general shape and bearing against said cylindrical surface of the cavity of the socket between the sealing element and the protective ring and an annular web portion which adjoins said lip portion and is transverse with respect to the axis of the pipes.

Claim 5

A joint as claimed in claim 2, wherein the outer lip portion of the closure ring is slightly frustoconical and divergent in a direction away from the annular web portion.

Claim 6

A joint as claimed in claim 2, wherein the web portion of the closure ring lies against the protective ring.

Claim 7

A joint as claimed in claim 4, wherein only the annular web portion of the closure ring is applied against the protective ring.

Claim 8

A joint as claimed in claim 5, wherein the median radial portion of the closure ring is in adhering relation to the protective ring.

Claim 9

A joint as claimed in claim 5, wherein the web portion of the closure ring has sufficient thickness to render it rigid.

Claim 10

A joint as claimed in claim 1, wherein the axial dimensions of the cavity, the sealing element, and the protective ring, are such that there remains a free axial space between the sealing element and the protective ring, the closure ring being disposed in said space.

Claim 11

A joint as claimed in claim 8, wherein the axial dimension of the outer lip portion of the closure ring and the axial dimension of the free axial space between the sealing element and the protective ring are such that the outer lip portion partially overlaps the sealing element.

Claim 12

A joint as claimed in claim 2, wherein the web portion has a radially inner peripheral edge which is very close to the male end without being however in contact with the male end.

Claim 13

A pipe sealing joint comprising a male end of a first pipe and a socket of a second pipe, the second pipe having a body portion axially adjacent to and rigid with the socket and the socket defining a cavity which is coaxial with the male end and defines with the male end an annular space and includes a substantially cylindrical surface, a sealing element having at least one portion which is disposed in the cavity and is in direct radial contact with the male end and the socket and in radially compressed condition between the male end and the socket, and means for partitioning off the sealing element from the interior of the pipes and thereby protecting the sealing element from the substance conveyed in the pipes and comprising a protective ring of flexible material placed in the cavity at an end of the cavity adjacent the body portion, and a closure ring which is of a material resisting corrosion by said substance and is disposed in the cavity between the sealing element and the protective ring, the closure ring extending radially across the whole of said annular space and comprising an outer circumferentially continuous annular lip portion having a substantially cylindrical general shape and bearing against said cylindrical surface of the cavity of the socket between the sealing element and the protective ring, an annular web portion which adjoins said lip portion and is transverse with respect to the axis of the pipes and a circumferentially continuous inner lip portion which extends from the web portion and is disposed axially on the opposite side of the web portion to the outer lip portion and has a substantially cylindrical general shape, the male end having a substantially cylindrical outer surface and the inner lip portion bearing against the cylindrical surface of the male end.

Claim 14

A pipe sealing joint comprising a male end of a first pipe and a socket of a second pipe, the second pipe having a body portion axially adjacent to and rigid with the socket and the socket defining a cavity which is coaxial with the male end and defines with the male end an annular space and includes a substantially cylindrical surface, a sealing element having at least one portion which is disposed in the cavity and is in direct radial contact with the male end and the socket and in radially compressed condition between the male end and the socket, and means for partitioning off the sealing element from the interior of the pipes and thereby protecting the sealing element from the substance conveyed in the pipes and comprising a protective ring of flexible material placed in the cavity at an end of the cavity adjacent the body portion, and a closure ring which is of a material resisting corrosion by said substance and is disposed in the cavity between the sealing element and the protective ring, the closure ring extending radially across the whole of said annular space and comprising an outer circumferentially continuous annular lip portion having a substantially cylindrical general shape and bearing against said cylindrical surface of the cavity of the socket between the sealing element and the protective ring, an annular web portion which adjoins said lip portion and is transverse with respect to the axis of the pipes and a circumferentially continuous inner lip portion which extends from the web portion and is disposed axially on the opposite side of the web portion to the outer lip portion and has a substantially cylindrical general shape, the male end having a substantially cylindrical outer surface and the inner lip portion bearing against the cylindrical surface of the male end.

Claim 15

A joint as claimed in claim 11, wherein the inner lip portion of the protective ring is slightly frustoconical and convergent in a direction away from the web portion and bears against said cylindrical surface in an annular continuous portion defining a free peripheral edge of the outer lip portion.

Claim 16

A joint as claimed in claim 12, wherein the inner lip portion of the closure ring has a radially inner free edge which has a diameter less than the outside diameter of the male end in the free state of the closure ring before introduction of the male end into the closure ring whereby the inner lip portion grips the male end in the assembled joint.

Claim 17

A joint as claimed in claim 2, wherein the outer lip portion of the closure ring has a radially outer free edge which has an outside diameter which is greater than the inside diameter of said cylindrical surface of the cavity in the free state of the closure ring before its introduction into the cavity whereby the outer lip portion is applied radially tightly against said cylindrical surface in the assembled joint.

Claim 18

A joint as claimed in claim 1, wherein the closure ring is a thin hot-formed sheet of an elastic substance.

Claim 19

A joint as claimed in claim 1, wherein the closure ring is a moulded elastic material.

Claim 20

A joint as claimed in claim 1, wherein the closure ring is composed of polyamide.

Claim 21

A pipe sealing joint comprising a male end of a first pipe and a socket of a second pipe, the second pipe having a body portion axially adjacent to and rigid with the socket and the socket defining a cavity which is coaxial with the male end and defines with the male end an annular space and includes a substantially cylindrical surface, a sealing element having at least one portion which is disposed in the cavity and is in direct radial contact with the male end and the socket and in radially compressed condition between the male end and the socket, and means for partitioning off the sealing element from the interior of the pipes and thereby protecting the sealing element from the substance conveyed in the pipes and comprising a protective ring of flexible material placed in the cavity at an end of the cavity adjacent the body portion, and a closure ring which is of a material resisting corrosion by said substance and is disposed in the cavity between the sealing element and the protective ring, the closure ring extending radially across substantially the whole of said annular space and comprising a circumferentially continuous annular outer lip portion which has substantially the shape of a cylinder and bears against said cylindrical surface, and an annular member which has an L-shaped section and is made from the same material as the closure ring and covers the protective ring on a radially outer face of the protective ring and on a face of the protective ring facing the body of the pipe, the annular member having a radially extending annular portion which has an inner peripheral edge which is very close to the male end without however touching the male end.

Claim 22

A pipe sealing joint comprising a male end of a first pipe and a socket of a second pipe, the second pipe having a body portion axially adjacent to and rigid with the socket and the socket defining a cavity which is coaxial with the male end and defines with the male end an annular space and includes a substantially cylindrical surface, a sealing element having at least one portion which is disposed in the cavity and is in direct radial contact with the male end and the socket and in radially compressed condition between the male end and the socket, and means for partitioning off the sealing element from the interior of the pipes and thereby protecting the sealing element from the substance conveyed in the pipes and comprising a protective ring of flexible material placed in the cavity at an end of the cavity adjacent the body portion, and a closure ring which is of a material resisting corrosion by said substance and is disposed in the cavity between the sealing element and the protective ring, the closure ring extending radially across substantially the whole of said annular space and comprising a circumferentially continuous annular outer lip portion which has substantially the shape of a cylinder and bears against said cylindrical surface, and an annular member which has an L-shaped section and is made from the same material as the closure ring and covers the protective ring on a radially outer face of the protective ring and on a face of the protective ring facing the body of the pipe, the annular member having a radially extending annular portion which has an inner peripheral edge which is very close to the male end without however touching the male end.

Claim 23

A joint as claimed in claim 1, further comprising a metal coil spring having non-contacting coils embedded in an inner edge portion of the protective ring and facing the body part of the pipe.