An exhaust conduit for a marine exhaust system includes an inlet end portion connectable to an exhaust manifold, an outlet end portion that directs exhaust gases toward an exhaust system outlet, a catalytic converter assembly arranged between the inlet and outlet end portions, and inner and outer tubes. The inner tube directs exhaust gases from the exhaust manifold to the catalytic converter assembly, and the outer tube surrounds the inner tube to define a cooling liquid passage between the inner and outer tubes. A flange is secured to the inner and outer tubes at inlet ends thereof, the flange being connectable to an outlet of the exhaust manifold. The inner tube has a uniform diameter between the flange and the catalytic converter assembly, and is welded to the flange independently of the outer tube. First and second welds join the inner and outer tubes to the flange at radially inner and outer faces, respectively, of a flange rim.

Aspects of the disclosure are directed to a tube assembly comprising: a first tube having a radial exterior surface, a second tube composed of a plurality of segments, the first tube co-axially nested within the second tube, at least a first spacer coupled to the first tube, and a second spacer coupled to the at least a first spacer, where a first segment of the plurality of segments is coupled to a first axial end of the second spacer, and a second segment of the plurality of segments is coupled to a second axial end of the second spacer.

A segment is fitted by screw-fastening for implementing a fluid transport pipe for transporting a fluid, the pipe including an inner wall and an outer wall, the segment including an inner tube and an outer tube that define an annular space between them. The segment includes in particular one heating duct placed in its annular space and opening out at either end of its annular space, the annular space being designed to be closed hermetically in order to enable it to be brought to a reduced pressure. A method of manufacturing the segment and a method of implementing the fluid transport pipe is described.

A double wall tube assembly includes an inner tube extending in an axial direction between two opposed ends of the inner tube. A sleeve fitting is mounted to one end of the inner tube. An outer tube outboard of the inner tube extends in the axial direction between two opposed ends of the outer tube. A collar fitting is mounted to one end of the outer tube wherein the collar fitting is outboard of the sleeve fitting.

Provided is a chemical injection system for connection to a chemical tank and a process line. The system includes a pump box configured to attach to the tank, the pump box including a body defining an interior, a pump assembly disposed within the interior of the body of the pump box, and an injection assembly configured to be fluidly coupled to the pump box. The injection assembly includes an injection lance having a flange and a stem, a first seal abutting a first side of the flange of the injection lance, and a second seal abutting a second side of the flange of the injection lance.

Double pipe system with a primary pipeline conducting a medium and a secondary pipeline which is arranged around the primary pipeline for protection, containing pipes and fittings of the primary pipeline, wherein the pipes and fittings of the primary pipeline are connected together, and pipes and fittings of the surrounding secondary pipeline, wherein the pipes are configured as one-piece plastics pipes and the fittings are configured as half-shells, wherein the half-shells of the fittings and the adjoining pipes of the secondary pipeline are connected together by means of electric welding sleeves, or in that the half-shells of the fittings and the adjoining fittings consisting of half-shells are connected together by means of electric welding sleeves.

A shrouded pipe formed from inner and outer pipe sections, the inner pipe section having an outwardly projecting flange joining the outer pipe section, and the outer pipe section having an inwardly projecting flange joining the inner pipe section, an annular volume between the inner and outer pipe sections providing a secondary fluid path. The flanges control axial position of the inner pipe section. By providing one flange which extends radially outwardly and one which extends radially inwardly, assembly is possible of the shrouded pipe by inserting the inner pipe section into the outer pipe section, without modification of the outer pipe section or inner pipe section. The first and second flanges ensure no unwanted contact between the inner and outer pipe sections, and therefore to prevent damage to the primary fluid path. The first and second flanges ensure good load distribution between the inner and outer pipe sections.

A method of manufacturing a shrouded pipe comprising an inner pipe section for providing a primary fluid path and an outer pipe section for enclosing the inner pipe section to provide a secondary fluid path. The method includes opening the outer pipe section by separating first and second longitudinal edges which split the outer pipe section along a longitudinal line, assembling the outer pipe section with the inner pipe section by passing the inner pipe section between the separated first and second longitudinal edges, and closing the outer pipe section by bringing the first and second longitudinal edges together and joining the first and second longitudinal edges together. An advantage of this method is that close manufacturing tolerances can be achieved without a complex or difficult assembly process.

Provided is a connection assembly for connecting to inner and outer hoses. The connection assembly includes a first connector assembly, a second connector assembly, a first hose connector assembly coupled to the connector assembly and configured to be coupled to the inner and outer hoses, the first hose connector assembly including a first tube connector configured to be coupled to the inner hose and a first collar configured to be coupled to the outer hose, and a second hose connector assembly coupled to the second connector assembly and configured to be coupled to the inner and outer hoses, the second hose connector assembly including a second tube connector configured to be coupled to the inner hose and a second collar configured to be coupled to the outer hose, wherein the second tube connector has a cross-sectional area that is smaller than a cross-sectional area of the first tube connector.

A swivel knuckle assembly for interconnecting a motor and a supply line. The knuckle assembly may include a bearing member to reduce a coefficient of friction. A locking mechanism is disclosed to connect members of the knuckle assembly.