A method for producing a rotor blade of a wind turbine includes the following steps: a) providing at least two different components of the rotor blade, b) placing a resistive element between the components, c) placing a thermoplastic or weldable thermoset resin between the components, d) energizing the resistive element so that the resistive element applies heat to the thermoplastic or weldable thermoset resin to melt or to soften it, and e) joining the components together by means of the molten or softened thermoplastic or weldable thermoset resin.

The present disclosure provides a wind turbine blade with an improved trailing edge structure and a manufacturing method thereof. The wind turbine blade includes an upper shell, a lower shell, and a trailing edge, where a trailing edge bonding region enclosed by the upper shell, the lower shell and the trailing edge is filled with composite materials, and the composite materials are discontinuous in an airfoil chordwise direction. The manufacturing method includes the following steps: S1: manufacturing reinforcements with a same cross-sectional shape as the trailing edge filling region for composite materials; and S2: integrally molding the reinforcements, a fiber fabric and the upper shell, providing the lower shell, combining the upper shell and the lower shell, and performing heating for curing and molding. The discontinuous filling structure reduces usages of the adhesive and the reinforcements of the composite materials. The small web can improve a strength of the trailing edge region, and reduce a bonding width of the trailing edge. Therefore, the present disclosure realizes a light weight of the wind turbine blade.

A method of joining polymer-lined pipe sections end-to-end comprises friction welding a polymer liner bridge fitting to parent liners of the pipe sections and welding metallic outer pipes of the pipe sections to each other before, during or after the friction welding operation. The fitting may be engaged telescopically with the pipe sections in socket formations formed by the parent liners. Friction welding is effected by relative rotational movement between the fitting and the pipe sections about a common longitudinal axis. A spinning tool is advanced longitudinally within at least one of the pipe sections, inserted into the fitting, anchored within at least one of the pipe sections, engaged with the fitting and rotated to effect the relative rotational movement. This friction-welds the fitting to the parent liners simultaneously at interfaces located at respective ends of the fitting.

A method for assembling a rotor blade of a wind turbine: a) providing at least two different rotor blade modules that segment the rotor blade along a longitudinal direction thereof, wherein each rotor blade module has a sloped interface section that include a weldable thermoplastic resin and/or a weldable thermoset resin (M, b) providing a resistive element, c) arranging the rotor blade modules and the resistive element in such a way that sloped interface sections face each other and the resistive element is sandwiched between the sloped interface sections, d) energizing the resistive element to apply heat to a weldable thermoplastic resin and/or the weldable thermoset resin to melt or to soften it, and e) joining the sloped interface sections together at a joint by means of the molten or softened weldable thermoplastic resin and/or the weldable thermoset resin to form the rotor blade.

To connect two plastic pipes 3 together, an induction connection sleeve 1 is used, which is provided with annular recesses 5 into which the pipes 3 with the ends 3A are pushed. Subsequently, induction heating elements 9 present in the induction connecting sleeve are heated with induction hand pliers 21 and the induction connecting sleeve is pressed against the end 3A of one of the tubes 3. The induction connection sleeve fuses to the tube. Because the induction hand pliers 21 are provided with ribs 27, grooves 19 are pressed into the pipe wall 3B in order to check whether sufficient heating and pressing has taken place over the entire circumference to obtain a gastight connection.