A pre-stressed concrete pipe is made by casting a concrete pipe inside a metal cylinder and then being pre-stressed by injecting solidifying compound under pressure into the boundary between the metal cylinder and concrete pipe, and includes a pair of end rings within the metal cylinder, each having a metal ring with an annular groove and an elastic band having a curved end to provide a rounded corner on the concrete pipe. After the solidifying compound is solidified, the concrete pipe retains the compression increasing its strength to withstand pressure, and moments caused by external loads. The pre-stressed concrete pipe further includes a bell ring mounted at one end and a spigot ring having a gasket ring at the other end. A bell clamp is mounted on the bell ring.

A pre-stressed concrete pipe is made by casting a concrete pipe inside a metal cylinder and then being pre-stressed by injecting solidifying compound under pressure into the boundary between the metal cylinder and concrete pipe, and includes a pair of end rings within the metal cylinder, each having a metal ring with an annular groove and an elastic band having a curved end to provide a rounded corner on the concrete pipe. After the solidifying compound is solidified, the concrete pipe retains the compression increasing its strength to withstand pressure, and moments caused by external loads. The pre-stressed concrete pipe further includes a bell ring mounted at one end and a spigot ring having a gasket ring at the other end. A bell clamp is mounted on the bell ring.

A carbon steel-concrete/cement mortar-stainless steel composite submarine pipeline belongs to the technical field of marine structure engineering. The composite submarine pipeline is formed by connecting several composite sub-pipelines arranged sequentially along an axial direction of the pipeline, each composite sub-pipeline has an identical structure and includes an outer carbon steel pipe and an inner stainless steel pipe each having a circular cross section and concentrically placed, concrete or cement mortar is filled between the outer carbon steel pipe and the inner stainless steel pipe to form a sandwiched structure with a circular ring-shaped cross section. Between two adjacent composite sub-pipelines, the welding line of the inner stainless steel pipelines is covered by the concrete/cement mortar, and the fatigue performance of the inner stainless steel pipes at the welding line can be improved effectively.

A carbon steel-concrete/cement mortar-stainless steel composite submarine pipeline belongs to the technical field of marine structure engineering. The composite submarine pipeline is formed by connecting several composite sub-pipelines arranged sequentially along an axial direction of the pipeline, each composite sub-pipeline has an identical structure and includes an outer carbon steel pipe and an inner stainless steel pipe each having a circular cross section and concentrically placed, concrete or cement mortar is filled between the outer carbon steel pipe and the inner stainless steel pipe to form a sandwiched structure with a circular ring-shaped cross section. Between two adjacent composite sub-pipelines, the welding line of the inner stainless steel pipelines is covered by the concrete/cement mortar, and the fatigue performance of the inner stainless steel pipes at the welding line can be improved effectively.

A method of cutting and removing a section of prestressed concrete cylinder pipe and then installing a replacement valve while the pipeline is fully pressurized uses a replacement valve body with two cylinders that match the openings of the cut pipe. Inside each of the two cylinders is a cut-covering assembly which includes a cylindrical elastomeric seal and a mechanical linkage to move the seal in and out of the cut pipe. The replacement valve body further includes a rotatable valve in a central portion of the valve, and when the cylinder ends of the replacement valve body are positioned adjacent the bores of cut pipe ends, the valve can be rotated to move linkage assemblies that control the elastomeric seals in and out of each of the cut-covering assemblies into the bores of the cut pipe ends, thereby covering gaps created when the pipe was cut and placing the pipe ends in fluid-tight engagement with the replacement valve body.

The present invention relates to a pipe for transporting gas, notably carbon dioxide, comprising at least one tubular element, tubular element (1) consisting of a juxtaposition of concentric layers comprising, from inside to outside, at least one sealing layer (5), a wall including a prestressed concrete layer (6) and at least one circumferential mechanical reinforcement layer (8). Furthermore, the concrete making up prestressed concrete layer (6) is selected from among the ultra-high performance fibre-reinforced concretes (UHPFRC).

The present invention relates to a pipe for transporting gas, notably carbon dioxide, comprising at least one tubular element, tubular element (1) consisting of a juxtaposition of concentric layers comprising, from inside to outside, at least one sealing layer (5), a wall including a prestressed concrete layer (6) and at least one circumferential mechanical reinforcement layer (8). Furthermore, the concrete making up prestressed concrete layer (6) is selected from among the ultra-high performance fibre-reinforced concretes (UHPFRC).

An integrated jacking pipe comprising a concrete jacking envelope integrally-formed with and encircling a metal pipe, wherein said metal pipe comprises a spigot protruding from said concrete jacking envelope and a bell whose diameter is larger than a diameter of said spigot.

An integrated jacking pipe comprising a concrete jacking envelope integrally-formed with and encircling a metal pipe, wherein said metal pipe comprises a spigot protruding from said concrete jacking envelope and a bell whose diameter is larger than a diameter of said spigot.

The present invention relates to a process for producing corrosion resistant alloy-clad metal pipes by: (a) providing one or more pipes to be clad; (b) providing an exothermic mixture; 5 (c) loading and distributing the exothermic mixture into the one or more pipes in a cladding assembly at a rotational speed suitable to generate a centrifugal force of at most 10 times the gravitational force; (d) igniting the loaded exothermic mixture using an ignition system at a rotational speed generating a centrifugal force of at least 50 times the gravitational force; 10 and (e) applying a post cladding pipe procedure.