A welding apparatus (1) for radio-frequency, RF, welding, comprises: a clamp (10) having two electrodes (100, 101; 100′, 101′) being movable with respect to one another for clamping one or more items (2; 2′) therebetween for a welding process; and an RF power supply (11) for providing an RF welding current to the electrodes (100, 101; 100′, 101′) of the clamp (10), the RF power supply being adapted to change the frequency of the RF welding current during the welding process.

A system for fusing thermoplastic composite structures includes a skin and a substructure on an inner surface of the skin. The system also includes a shaping surface of a tool, with the skin laid up on the shaping surface. The shaping surface is configured to maintain the shape of an outer mold line. The system further includes at least one insulation layer applied over a flange of the substructure and over exposed portions of the inner surface of the skin not in contact with the substructure, and a vacuum bag at least partly enclosing the skin and the substructure. Heat can be applied to the shaping surface to fuse the substructure to the skin such that the skin exceeds its melting point and at least a portion of a raised segment of the substructure does not exceed its melting point.

The invention relates to improvements of a heating means particularly in a vertical flow-wrapper.

A laser welding system is directed to simultaneously joining respective layers of a first bag and a second bag. The system includes a first film layer adjacent to a second film layer for forming the first bag, and a third film layer adjacent to a fourth film layer for forming the second bag, each layer of the plurality of film layers being made of a thermoplastic material that absorbs laser radiation having a wavelength of about 2 microns. A non-absorbing carrier film layer is positioned between the second film layer and the third film layer, the non-absorbing carrier film layer being made of a material that transmits substantially all energy of the laser radiation. A laser source applies the laser radiation toward portions of the plurality of film layers to be joined, forming the first bag generally simultaneously with the second bag.

A joining material for laser welding, a laser welding method using the same, and a laser joined body using the laser welding method. The joining material includes a polymer matrix and a needle-shaped inorganic filler. The polymer matrix includes a polypropylene resin having a melt index of 80 g/10 min or more to 95 g/10 min or less as measured at a temperature of 230° C. and a load of 2.16 kg, and the needle-shaped inorganic filler has an aspect ratio of 10:1 to 20:1.

A method of manufacturing an armour layer of a flexible pipe for transporting fluid from a subsea location and apparatus are provided. The method comprises winding a first length of composite tape to form a first section of the armour layer and positioning an end region of the first length of composite tape over an end region of a second length of composite tape to form an overlapping tape section. Heat and pressure is applied to the overlapping tape section to form a joined overlapping tape section in which the first length of tape is joined to the second length of tape such that the joined overlapping tape section has a lap shear strength of at least 11 MPa. The joined overlapping tape section and the second length of composite tape are wound to form a second section of the armour layer.

Provided among other things is a method of affixing a small, single chip to a plastic item, the chip having a top surface having length and width dimensions, and having a height, the method comprising: (1) vacuum adhering a top-oriented surface of the chip to a probe of outer dimensions comparable to or smaller than those of the length and width; (2) conveying heat to the chip via the probe such that a bottom-oriented surface of the chip is sufficiently hot to melt the plastic; (3) applying via the probe the chip to the plastic such that the chip embeds in the plastic; and (4) releasing the chip from the probe, wherein the largest of the length and width is about 500 microns or less, and height is no more than about the smallest of length and width.

A welder for joining two polymeric sheets together using a wedged heating element allows for a heating profile on opposite faces of the heating element to be varied by controlling where each of the polymeric sheets contacts the corresponding face.

The invention relates to a method for the application of heating mats (10) on a wing/blade of a wind power station or other devices for the purpose of achieving deicing also during operation when necessary. Temperature measurement and de-icing take place by means of pulsed current to the heating mat (10). The invention also relates to an arrangement.

The invention relates to a method for checking, prior to welding, two components made of polymer material, the method comprising a step of determining respective values relating to the roughness of the components, a step of determining respective values relating to the cleanliness of the components, a step of determining respective values relating to the temperature of the components and automated means for halting progression to a subsequent method step should the predetermined conditions not be met.