Disclosed embodiments provide an electrofusion pipe coupler with mechanical support. The electrofusion pipe coupler comprises a coupler housing. A wire is configured and disposed within the housing. Electrodes are affixed to the coupler housing and in electrical contact with the wire. A threaded pattern is formed in an outer surface of the coupler housing. Gripping wedges are affixed to the coupler housing. Each gripping wedge extends from the coupler housing. A nut is attached to the coupler housing, engaging with the threaded pattern, and compressing the wedges against the connecting pipes. This serves to provide axial load transfer from the connecting pipes to the coupler housing via the wedges, thereby providing improved mechanical stability for such pipe assemblies.

The invention relates to the use of a low Tg compatible resin as an adhesive layer for the welding of a thermoplastic composite structure to a thermoplastic or thermoset structure. The invention is especially good for the welding of large parts, such as wind turbine halves and spar caps. A useful thermoplastic composite is one formed by the infusion and curing of long fibers by a reactive acrylic liquid resin system, such as ELIUM® resin systems from Arkema.

An electrofusion joint includes a main body and a heating wire. The main body is configured to be connected to a first resin pipe and a second resin pipe containing a thermoplastic resin. The heating wire is disposed in the main body. The heating wire includes a conducting wire and an insulating cover film that is provided around the conducting wire. The insulating cover film has a melting point of at least 230 degrees.

Disclosed is a method of resistance welding between composite articles. A conductive element is provided between faying surfaces, having a plurality of lower resistivity electrode portions spaced apart along the length of the contact area between the composite articles. The electrode portions can be used to spot weld across the electrode portions, and along a longitudinal portion of the conductive element between the electrode portions by application of an electrical current. Also disclosed are apparatus for use in the resistance welding methods and composite articles and structures and elements incorporating the conductive element.

The electrofusion joint includes a tubular main body, a stopper portion, a first heat generating section, and a second heat generating section. The tubular main body includes a joint receiving portion. The stopper portion projects inward on the inner surface of the main body. The first heat generating section includes a heating wire wound and arranged at the joint receiving portion. The second heat generating section includes a heating wire wound so that wound parts are adjacent to each other and the heating wire is disposed in the stopper portion. The first heat generating section includes at least one heat generating portion in which the heating wire is wound so that the wound parts are adjacent to each other.

Disclosed is a method of resistance welding between composite articles. A conductive element is provided between faying surfaces, having a plurality of lower resistivity electrode portions spaced apart along the length of the contact area between the composite articles. The electrode portions can be used to spot weld across the electrode portions, and along a longitudinal portion of the conductive element between the electrode portions by application of an electrical current. Also disclosed are apparatus for use in the resistance welding methods and composite articles and structures and elements incorporating the conductive element.

A system for coupling pipes includes a first pipe having a tapered, spigot end; a second pipe having a tapered, spigot end; a coupler having two tapered socket ends adapted to internally receive the respective tapered, spigot ends of the first pipe and the second pipe; and a resistive element. The first pipe, the second pipe, and the coupler are made from a reinforced thermosetting resin (RTR). The resistive element includes a first layer and a second layer of thermoplastic material; and an electrically conducting resistive heating element with positive and negative terminals for connecting electrical power. The electrically conducting resistive heating element is sandwiched by the first layer and the second layer of thermoplastic material. The resistive element is disposed between an interior of the coupler and at least one of: an exterior of the first pipe and an exterior of the second pipe. Upon application of electrical power to the positive and negative terminals of the resistive element, the electrically conducting resistive heating element generates heat sufficient to melt the thermoplastic material such that, when the heat is removed, the hardened thermoplastic material seals the first pipe and/or the second pipe to the coupler.

A large tubular plastic tank, for use in holding unpressurized water or wastewater, is formed by fusion welding together half-shell parts at lengthwise flange joints to form a tubular body. Then, end caps are fusion welded onto the outermost ends of the tubular body and an assembly of two or more bodies. Fusion weld elements are secured beforehand to the joining surfaces of the tank parts at a factory; the tank parts are then economically stored or shipped in nested condition to a fabrication site remote from the manufacturing site. Electric or electromagnetic energy is used to melt in situ the fusion weld elements which are captured between the joining surfaces of the parts.

A method of manufacturing a heat exchanger array that includes stacking a plurality of heat exchanger units in an aligned configuration with respective first ports of the plurality of heat exchanger units aligned. The method can further include generating heat in the first coupling elements at the same time and at a temperature sufficient to generate a first plurality of respective couplings between adjacent sheets of adjacent heat exchanger units about adjacent first ports and without a coupling being generated between the first and second sheets of a given heat exchanger unit.

A wind turbine blade 2 comprises a profiled contour including a leading edge 34 and a trailing edge 33 as well as a pressure side and a suction side. The profiled contour is formed by a first shell part 10 and a second shell part 15 being bonded together in a bonding region between the first and the second shell part by a curable bonding means 40. The first and the second shell part 10; 15 are formed in a fiber-reinforced polymer. The wind turbine blade further comprises resistive heating means 50 being arranged in thermal connection with the bonding means 40 such that the resistive heating means 50 supplies heat for curing of the curable bonding means 40 during assembling of the wind turbine blade.