The invention relates to a sealing ring including, axially, a main portion (2) and a secondary portion (3), connected by a weakened intermediate portion (4) which can be broken under an axial force applied between the main portion and the secondary portion, the main portion (2) including an annular sealing sleeve (5) and a projecting outer shoulder (6) arranged at the end of the annular sealing sleeve (5), opposite the breakable portion (4), and the secondary portion (3) including a projecting inner shoulder (10). Said annular sleeve (5) of the main portion (2) of the ring can be inserted between ducts (16, 17) that are inserted into one another, said projecting outer shoulder (6) of the main portion (2) abutting against the end of the outer duct surrounding the inner duct, and said projecting inner shoulder (10) of the secondary portion (3) abutting against the end of the outer tube that is inserted into the outer duct.

Trenchless methods for forming a curved hole channel with a steel sleeve and pipeline lifting are provided, including steps of: (T1) drilling a straight hole channel, and inserting the steel sleeve into the straight hole channel; (T2) inserting a guiding pipe into the steel sleeve, and determining a bending direction of a hole channel to be formed; and (T3) inserting a flexible steel-wire pipe into the guiding pipe, and punching to form the curved hole channel. With applying the creative trenchless method for forming the curved hole channel, a specially-made grouting pipe is accurately inserted to a bottom of a subsiding pipeline section, so that a polymer material is conveniently injected to a bottom of a disease position. Though utilizing an expansion force generated by the polymer material, the subsiding pipeline section is uplifted, so as to realize trenchless repairing.

Trenchless methods for forming a curved hole channel with a steel sleeve and pipeline lifting are provided, including steps of: (T1) drilling a straight hole channel, and inserting the steel sleeve into the straight hole channel; (T2) inserting a guiding pipe into the steel sleeve, and determining a bending direction of a hole channel to be formed; and (T3) inserting a flexible steel-wire pipe into the guiding pipe, and punching to form the curved hole channel. With applying the creative trenchless method for forming the curved hole channel, a specially-made grouting pipe is accurately inserted to a bottom of a subsiding pipeline section, so that a polymer material is conveniently injected to a bottom of a disease position. Though utilizing an expansion force generated by the polymer material, the subsiding pipeline section is uplifted, so as to realize trenchless repairing.

In a state in which a ferrule 10 is sandwiched and fixed between a ferrule receiving part 20 and a ferrule pressing part 30, the ferrule 10 is urged toward the ferrule receiving part 20 side by an urging member 33. With this structure, without configuring such that the ferrule pressing part is screwed in the ferrule receiving part by rotating several times, the ferrule 10 can be pressed toward the ferrule receiving part 20 side by a sufficient pressing force by the urging force of the urging member 33. Therefore, the attaching work of the column 2 can be performed more easily.

In a state in which a ferrule 10 is sandwiched and fixed between a ferrule receiving part 20 and a ferrule pressing part 30, the ferrule 10 is urged toward the ferrule receiving part 20 side by an urging member 33. With this structure, without configuring such that the ferrule pressing part is screwed in the ferrule receiving part by rotating several times, the ferrule 10 can be pressed toward the ferrule receiving part 20 side by a sufficient pressing force by the urging force of the urging member 33. Therefore, the attaching work of the column 2 can be performed more easily.

A super-long thermal insulation steel jacket pipe and a machining process for making such a pipe are provided. The pipe is designed to exhibit good thermal insulation performance and corrosion resistance. An annular cavity of the pipe is in a vacuum state, and the pipe is internally provided with a support frame and filled with a phase change material. When the pipe is used for underground energy exploitation, temperature in a working steel pipe in the pipe can be effectively kept unaffected when external temperature decreases. The steel jacket pipe has long service life, and can greatly reduce costs of exploitation of petroleum and/or of an underground heat source, such as by reducing a heat loss in exploitation.

A super-long thermal insulation steel jacket pipe and a machining process for making such a pipe are provided. The pipe is designed to exhibit good thermal insulation performance and corrosion resistance. An annular cavity of the pipe is in a vacuum state, and the pipe is internally provided with a support frame and filled with a phase change material. When the pipe is used for underground energy exploitation, temperature in a working steel pipe in the pipe can be effectively kept unaffected when external temperature decreases. The steel jacket pipe has long service life, and can greatly reduce costs of exploitation of petroleum and/or of an underground heat source, such as by reducing a heat loss in exploitation.

An improved cable protector sleeve comprises a sheet of flexible material having a first longitudinal edge opposite of a second longitudinal edge, a first fastening means proximate to the first longitudinal edge, and a second fastening means proximate to the second longitudinal edge. The first and second fastening means, which may be hook-and-loop fasteners, are preferably disposed on opposite sides of the sheet. The sheet is secured around a plurality of cables by removably fastening the first fastening means to the second fastening means. Optionally, at least one friction means, such as a row of stitches, transverses the sheet and increases friction between the sheet and the plurality of cables. The improved cable protector is thus easily installed around and removed from a plurality of cables, providing protection and organization to the cables.

An improved cable protector sleeve comprises a sheet of flexible material having a first longitudinal edge opposite of a second longitudinal edge, a first fastening means proximate to the first longitudinal edge, and a second fastening means proximate to the second longitudinal edge. The first and second fastening means, which may be hook-and-loop fasteners, are preferably disposed on opposite sides of the sheet. The sheet is secured around a plurality of cables by removably fastening the first fastening means to the second fastening means. Optionally, at least one friction means, such as a row of stitches, transverses the sheet and increases friction between the sheet and the plurality of cables. The improved cable protector is thus easily installed around and removed from a plurality of cables, providing protection and organization to the cables.

A pipe-in-pipe assembly with thermally-insulating spacers positioned in an annulus to act radially between inner and outer pipes is disclosed. The spacers have at least one circumferentially-extending array of circumferentially-spaced ribs that define longitudinally-extending passageways in gaps between neighbouring ribs of the array. Cables including heating elements extend longitudinally along, the annulus outside the inner pipe. The cables extend longitudinally along the passageways. At least one insulation layer disposed radially outboard of the cables has insulating elements disposed in the gaps between the ribs and/or an insulating layer extending around the inner pipe, positioned radially outboard of the ribs and bridging the gaps. Bands encircle and retain components of the insulation layer. Insulation may also be disposed on the inner pipe between first and second arrays of ribs, those arrays being spaced longitudinally from each other.