The present invention relates to a method of molding a shell part of a wind turbine blade comprising the steps of providing a mold (64) comprising a mold cavity (66) with a root end (68) and an opposing tip end (70), arranging one or more preformed sheets (72a, 72b, 72c) in the mold cavity (66), wherein each preformed sheet comprises a mixture of fibre rovings (82) and a binding agent, wherein the fibre rovings are at least partially joined together by means of the binding agent, and injecting the one or more preformed sheets (72a, 72b, 72c) with a resin to mold the shell part. The present invention also relates to a shell part of a wind turbine blade obtainable by said method, to a preformed sheet for use in said method and to a method of manufacturing said preformed sheet.

The present invention relates to a method of molding a shell part of a wind turbine blade comprising the steps of providing a mold (64) comprising a mold cavity (66) with a root end (68) and an opposing tip end (70), arranging one or more preformed sheets (72a, 72b, 72c) in the mold cavity (66), wherein each preformed sheet comprises a mixture of fibre rovings (82) and a binding agent, wherein the fibre rovings are at least partially joined together by means of the binding agent, and injecting the one or more preformed sheets (72a, 72b, 72c) with a resin to mold the shell part. The present invention also relates to a shell part of a wind turbine blade obtainable by said method, to a preformed sheet for use in said method and to a method of manufacturing said preformed sheet.

A method of manufacturing an article comprises etching an etched feature on a surface of a first polymeric sheet, and forming a fluid-filled bladder element from the first polymeric sheet, with the fluid-filled bladder element having a sealable internal cavity that retains fluid. The method includes assembling the bladder element in the article so that a first portion of the bladder element having the etched feature is exposed to view, and a second portion of the bladder element is blocked from view by the article. An article includes the bladder element with the etched feature.

A method of manufacturing an article comprises etching an etched feature on a surface of a first polymeric sheet, and forming a fluid-filled bladder element from the first polymeric sheet, with the fluid-filled bladder element having a sealable internal cavity that retains fluid. The method includes assembling the bladder element in the article so that a first portion of the bladder element having the etched feature is exposed to view, and a second portion of the bladder element is blocked from view by the article. An article includes the bladder element with the etched feature.

Disclosed are an embedded co-cured composite material with large-damping and electromagnetic wave absorbing properties and a preparation method and an application thereof, belonging to damping composite materials. The embedded co-cured composite material is formed by interlacing a plurality of electromagnetic wave absorbing prepreg layers and a plurality of electromagnetic wave absorbing damping layers. Each of the electromagnetic wave absorbing prepregs layers includes a fiber cloth, a micro-nano electromagnetic wave absorbing material and a resin. Contents of the micro-nano electromagnetic wave absorbing material in the electromagnetic wave absorbing prepreg layers and the electromagnetic wave absorbing damping layers have a gradient increase or decrease according to a sequence of the electromagnetic wave absorbing prepreg layers. Each of the electromagnetic wave absorbing damping layers includes a viscoelastic damping material and the micro-nano electromagnetic wave absorbing material.

Disclosed are an embedded co-cured composite material with large-damping and electromagnetic wave absorbing properties and a preparation method and an application thereof, belonging to damping composite materials. The embedded co-cured composite material is formed by interlacing a plurality of electromagnetic wave absorbing prepreg layers and a plurality of electromagnetic wave absorbing damping layers. Each of the electromagnetic wave absorbing prepregs layers includes a fiber cloth, a micro-nano electromagnetic wave absorbing material and a resin. Contents of the micro-nano electromagnetic wave absorbing material in the electromagnetic wave absorbing prepreg layers and the electromagnetic wave absorbing damping layers have a gradient increase or decrease according to a sequence of the electromagnetic wave absorbing prepreg layers. Each of the electromagnetic wave absorbing damping layers includes a viscoelastic damping material and the micro-nano electromagnetic wave absorbing material.

Methods and apparatus for additive manufactures of complex parts using co-aligned continuous fibers are disclosed. Filament subunits having complex shapes are fabricated and inserted into a mold cavity. The layup is compression molded to form a complex part having high tensile strength.

A method of making a brush includes providing a plurality of first filaments, each having a first end and a second end; bringing the plurality of first filaments into a first predetermined shape such that the first ends are arranged side by side on a common contour; fixedly connecting the first ends so that a first pre-tuft having the first predetermined shape and a connected first end is formed; bringing a second tuft element having a first end and a second end together with the first pre-tuft into a second predetermined shape such that the first end of the second tuft element and the connected first end of the first pre-tuft are arranged side by side on a common contour; fixedly connecting the connected first end of the first pre-tuft and the first end of the at least second tuft element so that a final tuft having the second predetermined shape and a connected end is formed; and attaching the final tuft to a brush body by overmolding the final tuft's connected end with a plastic material.

A method of making a brush includes providing a plurality of first filaments, each having a first end and a second end; bringing the plurality of first filaments into a first predetermined shape such that the first ends are arranged side by side on a common contour; fixedly connecting the first ends so that a first pre-tuft having the first predetermined shape and a connected first end is formed; bringing a second tuft element having a first end and a second end together with the first pre-tuft into a second predetermined shape such that the first end of the second tuft element and the connected first end of the first pre-tuft are arranged side by side on a common contour; fixedly connecting the connected first end of the first pre-tuft and the first end of the at least second tuft element so that a final tuft having the second predetermined shape and a connected end is formed; and attaching the final tuft to a brush body by overmolding the final tuft's connected end with a plastic material.

A high pressure obturator for a breech loaded, tube-launched projectile includes a generally annular ring having a central longitudinal axis and a radially inward portion. A flange portion is disposed radially outward of and partially contiguous with the radially inward portion. The flange portion extends axially forward and aft beyond the radially inward portion. The outer diameter of the flange portion decreases linearly from an aft most outer diameter to a forward most outer diameter. The obturator may be formed of a plastic material and include circumferential wraps of a high-strength fiber completely embedded in grooves in the obturator.