4results about How to "Avoid internal defects" patented technology

This invention discloses a high-performance meta-aramid / mica composite insulating paper and its preparation method. The paper is formed by wet papermaking and hot pressing of a mixed slurry composed of meta-aramid chopped fibers, meta-aramid precipitated fibers, and mica flakes. The composite insulating paper has a thermal decomposition temperature ≥425℃, tensile strength ≥52N / mm, tear strength ≥2.2N / mm, and voltage breakdown strength ≥13.8kV / mm. The mass ratio of chopped fibers to precipitated fibers is (50~80):(50~20). The amount of mica flakes added is 5wt%~10wt% of the total mass of the two aramid fibers. The hot pressing adopts a segmented hot pressing process of "low-temperature pre-pressing - medium-temperature strengthening - high-temperature setting". By controlling the key parameters of the precipitated fibers and optimizing the ratio of chopped fibers to precipitated fibers and the proportion of mica flakes added, the paper is prepared through processes such as raw material pretreatment, graded mixing and dissociation, wet papermaking, and segmented hot pressing. Advantages: Through multi-parameter coordinated control and process optimization, the technical bottlenecks such as the mechanical and insulation properties of existing aramid composite insulating paper and insufficient thermal stability have been solved.

The application discloses a low-cost soft mold manufacturing method applicable to a T-shaped rib reinforced skin structure, and comprises the following steps: adopting an isolation film and a vacuum bag to integrally encapsulate a laminated plate skin blank body, a T-shaped rib blank body and a T-shaped soft mold on a forming tool; adopting a hot press tank to perform co-curing forming of a "wet" state laminated plate skin and a "wet" state T-shaped rib according to the curing requirements allowed by the material specification of carbon fiber prepreg, and obtaining the T-shaped rib reinforced skin structure; the application has the beneficial effects that: through the structure splitting of step S1, the customization of special tooling (a forming tool, a T-shaped rib pre-compaction tool and a soft mold forming tool), the accurate positioning and cooperation of step S4 and the co-curing forming of the "wet" state laminated plate skin and the "wet" state T-shaped rib of step S6, the defects of poor adaptability of the T-shaped rib to the skin, easy interference of R angles, easy wrinkling of edges and the need of post-grinding in the traditional gluing process are effectively solved.

The utility model discloses a kind of co-cured composite material transmission shaft forming tool, including upper die, lower die and two cover plates;The upper die, lower die and two cover plates are closed to form the forming cavity of composite material transmission shaft;Two ends of the forming cavity have metal joint cavity.The utility model forms accurate composite material transmission shaft forming cavity by the close cooperation of upper die, lower die and two cover plates, ensure the effective control of size accuracy and shape accuracy during forming process, improve the overall quality of product, in addition, the metal joint cavity designed at the two ends of forming cavity, so that metal joint and composite material can be co-cured in the same process, strengthen the bonding strength between metal joint and composite material, improve the overall performance and reliability of transmission shaft.

This invention discloses a rapid prototyping system for porcelain insulators, relating to the field of porcelain insulator technology. It includes a workbench with a lifting assembly fixedly connected above it via a mounting bracket. An upper mold is fixed to the movable part at the bottom of the lifting assembly. A lower mold is fixed directly below the upper mold on the workbench. Vertical guide rods are provided at the four corners of the lower mold, with guide cones at the top (narrower at the top, wider at the bottom) and the same size as the guide rods at the bottom. Vertical through-type limiting tubes are provided at the four corners of the upper mold, with the inner wall of the limiting tubes slidingly fitting against the outer wall of the guide rods. Both the upper and lower molds are equipped with temperature control mechanisms, including heating grids and temperature sensors. The temperature sensors detect the temperature of the heating grids, and the power of the heating grids is controlled by a first control unit according to a preset temperature. The two first control units communicate in real time via a wireless communication unit to ensure that the heating grid temperatures are the same. The upper and lower molds and their heating grids are the same size. This invention allows for rapid preliminary shaping, accurate positioning, and uniform heating.