Packer for use when repairing underground pipe systems, where said packer comprises a flexible and/or expandable main body portion surrounding a hollow interior, said body portion having an elongated shape defining first and second ends in either end of the main body portion, and where heating means are arranged in the packer for heating the packer or at least the surface of the packer, and means are provided for pressurizing the interior of the packer thereby expanding the packer.

Packer for use when repairing underground pipe systems, where said packer comprises a flexible and/or expandable main body portion surrounding a hollow interior, said body portion having an elongated shape defining first and second ends in either end of the main body portion, and where heating means are arranged in the packer for heating the packer or at least the surface of the packer, and means are provided for pressurizing the interior of the packer thereby expanding the packer.

The present invention provides pipeline pigs for maintenance of a pipeline, the pig including two adjacent ovular sections generally symmetrically disposed about a vertical axis, a polymeric band disposed along the vertical axis, the band being adapted to reduce a cross section of the pig along the axis and a longitudinal inner support member disposed centrally along the ovular sections and perpendicularly to the vertical axis.

The present invention provides pipeline pigs for maintenance of a pipeline, the pig including two adjacent ovular sections generally symmetrically disposed about a vertical axis, a polymeric band disposed along the vertical axis, the band being adapted to reduce a cross section of the pig along the axis and a longitudinal inner support member disposed centrally along the ovular sections and perpendicularly to the vertical axis.

Pigs (10) are propelled forwards by a propulsion fluid in a pipeline (21). The pigs (10) have an upstream end (13), a downstream end (11), and an intermediate section (12). The intermediate section has a variable geometry chamber (16) associated therewith and one or more outwardly extending external pawl teeth (15). The pawl teeth are automatically displaceable outwardly relative to a longitudinal axis (9) in response to a pressure differential between a downstream pressure and an upstream pressure. The pig is configured such that a change in a geometry of the chamber in response to the pressure differential between the downstream pressure and the upstream pressure causes the one or more pawl teeth to automatically displace outwardly when the upstream pressure is less than the downstream pressure. When the pawl teeth are deployed, upstream displacement of the pig is inhibited. Various related systems (5) and methods are also disclosed.

Pigs (10) are propelled forwards by a propulsion fluid in a pipeline (21). The pigs (10) have an upstream end (13), a downstream end (11), and an intermediate section (12). The intermediate section has a variable geometry chamber (16) associated therewith and one or more outwardly extending external pawl teeth (15). The pawl teeth are automatically displaceable outwardly relative to a longitudinal axis (9) in response to a pressure differential between a downstream pressure and an upstream pressure. The pig is configured such that a change in a geometry of the chamber in response to the pressure differential between the downstream pressure and the upstream pressure causes the one or more pawl teeth to automatically displace outwardly when the upstream pressure is less than the downstream pressure. When the pawl teeth are deployed, upstream displacement of the pig is inhibited. Various related systems (5) and methods are also disclosed.

A method for refurbishing an existing host pipe, in which an in-situ longitudinal cut is made in the interior wall of a subterranean host pipe. An expansion tool is moved along a path inside the host pipe, stopping at one or more stations on the way. At each station, responsive to isolated outward radial force from the expansion tool, the interior diameter of the host pipe is increased via separation of the longitudinal cut. A new rigid liner pipe is inserted inside the expanded host pipe to operationally replace the host pipe. In some embodiments, grout is deployed in the annular space between liner pipe and host pipe. Expansion of the host pipe via separation of the longitudinal cut optimizes the refurbishment job and enables the original host pipe, as expanded, to contribute structurally to the refurbished pipe system.

A method for refurbishing an existing host pipe, in which an in-situ longitudinal cut is made in the interior wall of a subterranean host pipe. An expansion tool is moved along a path inside the host pipe, stopping at one or more stations on the way. At each station, responsive to isolated outward radial force from the expansion tool, the interior diameter of the host pipe is increased via separation of the longitudinal cut. A new rigid liner pipe is inserted inside the expanded host pipe to operationally replace the host pipe. In some embodiments, grout is deployed in the annular space between liner pipe and host pipe. Expansion of the host pipe via separation of the longitudinal cut optimizes the refurbishment job and enables the original host pipe, as expanded, to contribute structurally to the refurbished pipe system.

A vertical barrel of an internal diameter to receive a pig having a selected uncompressible diameter, a reducer to compress the pig to a compressed diameter and a fluid system to introduce fluid pressure into the upper end of the barrel to drive the pig through the reducer.

A vertical barrel of an internal diameter to receive a pig having a selected uncompressible diameter, a reducer to compress the pig to a compressed diameter and a fluid system to introduce fluid pressure into the upper end of the barrel to drive the pig through the reducer.