A pipeline connection structure includes a first pipe body, a second pipe body, and a connection sleeve assembly, wherein the first pipe body and the second pipe body are connected by the connection sleeve assembly. A compressor assembly has the pipeline connection structure.

Segmental duct coupler devices, systems, and methods are provided herein. A duct coupler device can include a single, discrete body of material for welding to a duct segment. A system, including a duct segment having a duct coupler device welded thereto, is provided. The connection or points of connection between the duct coupler device and the duct segment in the system are devoid of internal and/or external seals. The duct coupler device and system can be cast in concrete. Multiple concrete segments can be assembled together to form a bridge, a roadway, a building, a slab, or any other structure.

A hose assembly includes an inner core tube, a metal outer tube, a first coupling member, and a first collar. The first coupling member has an inboard nose portion extending into a first end of the inner core tube. The metal outer tube surrounds the inner core tube and terminates at a first end axially inward of the first end of the inner core tube, with an outer cavity disposed between the inner core tube and the metal outer tube. The first collar has an outboard clamping portion surrounding the nose portion for clamping retention of the first end of the inner core tube therebetween, and an inboard venting portion welded to the first end of the metal outer tube, with the inboard venting portion including a venting port in fluid communication with the outer cavity.

A system for laying pipe includes a conveyor configured to receive one or more pipes, and one or more friction stir welding (FSW) machines configured to connect the one or more pipes to a pipeline deployed toward a sea floor.

A system for securing first and second metal workpieces to a central metal workpiece located therebetween. The system includes clamps to secure the first and second metal workpieces in coaxial alignment with the central metal workpiece, which is rotatable about its axis. Heating elements heat opposed ends of the first metal workpiece and the central metal workpiece, and opposed ends of the second metal workpiece and the central metal workpiece, to a hot working temperature. While the opposed ends are at the hot working temperature, the heating elements are removed. The opposed end of the first metal workpiece is urged against the end opposed thereto of the rotating central metal workpiece, while the central metal workpiece rotates. At the same time, the rotating central metal workpiece is pulled against the second metal workpiece to engage the opposed ends thereof with each other. The workpieces are then allowed to cool.

A system for securing first and second metal workpieces to a central metal workpiece located therebetween. The system includes clamps to secure the first and second metal workpieces in coaxial alignment with the central metal workpiece, which is rotatable about its axis. Heating elements heat opposed ends of the first metal workpiece and the central metal workpiece, and opposed ends of the second metal workpiece and the central metal workpiece, to a hot working temperature. While the opposed ends are at the hot working temperature, the heating elements are removed. The opposed end of the first metal workpiece is urged against the end opposed thereto of the rotating central metal workpiece, while the central metal workpiece rotates. At the same time, the rotating central metal workpiece is pulled against the second metal workpiece to engage the opposed ends thereof with each other. The workpieces are then allowed to cool.

A device internally insulating a welded pipeline joint between pipes having an internal protective coating, in a first variant, includes a power actuator having a cylindrical elastic working member for radial expansion when excess pressure occurs inside its cavity. A cylindrical casing of elastic anti-adhesive material arranged coaxially on the member exterior can have channels for exhausting air and supplying a compound. In a second variant, the device sleevelessly insulates an annular space. A casing made of an anti-adhesive material is centrally reinforced by an elastic cord. Using a cylindrical elastic anti-adhesive casing coaxially arranged on the exterior of a power actuator elastic working member forms an annular space in the weld zone either using a protective sleeve, or by a reinforced casing portion. A vacuum in the space is filled by a compound. The elastic anti-adhesive material allows easy removal of the casing from the hardened compound surface.

Method for generating a compatibility index between two ends of two tubes, in particular before welding operations, the method comprising the steps of: (a) marking an angular reference (M0) on each of the two ends, (b) orbital measurement of an inside radius of each of the ends; (c) determining an index of angular compatibility (IND.sub.thētak) between the two ends for an angular deviation (⊖, theta) between the angular references of the ends, said angular compatibility index deriving from a maximum difference between the inside radii of each opposite end, (d) iterating the step of determining the angular compatibility index for several values for angular deviation between the angular references of the ends; (e) generating an overall score for compatibility (Hk) between said two ends, the overall compatibility score being a function of the angular compatibility indices determined for several angular deviation values.

A method for purging air from a structure to be joined by welding by feeding a liquid cryogen to the structure. The liquid cryogen will enter the structure, warm up and enter the gaseous phase very rapidly. The gaseous cryogen will displace the air that is present in the structure out of the structure and reduce the content of oxygen in the structure to about 10 parts per million when welding can begin.

A method for purging air from a structure to be joined by welding by feeding a liquid cryogen to the structure. The liquid cryogen will enter the structure, warm up and enter the gaseous phase very rapidly. The gaseous cryogen will displace the air that is present in the structure out of the structure and reduce the content of oxygen in the structure to about 10 parts per million when welding can begin.