Pressboard

About: Pressboard is a research topic. Over the lifetime, 1123 publications have been published within this topic receiving 9089 citations.

Influence of oil-flow to the breakdown characteristics of oil-pressboard insulation in converter transformer under compound electrical field

Abstract: Taken a composited insulation system of oil and pressboard filled in two parallel tabulate electrodes as research object, the oil-flow electrification experiment was carried out without applied voltage and under DC voltage. The relationship between leakage current and velocity was measured. The electric-field caused by oil-flow electrification was calculated. The breakdown characteristics experiment of the composited insulation system was carried out at different velocity, stressed by AC voltage, DC voltage and AC plus DC voltages with different AC voltage content. The result shows that, as the velocity increases, the breakdown voltage of the oil-pressboard composited insulation system may decrease and the electric-field caused by oil-flow electrification may increase. The oil-flow electrification will increase under DC electrification than that without applied voltage.

Hot pressboard with soft layers

Abstract: The utility model provides a hot pressboard with soft layers. The hot pressboard with the soft layers comprises the hot pressboard, and working faces of the hot pressboard contacting with slabs are all covered by the soft layers. According to the hot pressboard with the soft layers, forms of the soft layers can change with the forms of surfaces of the slabs, pressure can be lowered to a large extent, and perfect gluing can be achieved when the pressure is 1kg/cm2. As the pressure is lowered, a smaller hydraulic system can be adopted and the structure of a hot press can be simplified. Meanwhile, the amount of compression of decorative veneers can be reduced, and timbers of precious trees can be saved.

Paper pressing mechanism for upper paper separating device

Abstract: The utility model discloses a paper pressing mechanism for an upper paper separating device. The paper pressing mechanism for the upper paper separating device comprises a pressboard; a plurality of paper pressing buffers are arranged on the pressboard; each paper pressing buffer comprises a buffer bar and a fixed bracket; the buffer bar slidably passes through the fixed bracket; a damping spring is arranged below the fixed bracket and sleeved on the buffer bar; spacing nuts are respectively arranged at two ends of the buffer bar; the upper end of the damping spring is propped against the lower surface of the fixed bracket; the lower end of the damping spring is propped against the spacing nut at the lower end of the buffer bar; and the upper surface of the fixed bracket is propped against the spacing nut at the upper end of the buffer bar. When impacted, the pressboard can drive the buffer bar to compress the damping spring so as to enhance the buffering effect, reduce the impact to the pressboard, further reduce the abrasion and prolong the service life of the paper pressing mechanism.

A gasket pressure equipment mechanism for bottle cover spacer assembly

Abstract: The utility model discloses a gasket pressure equipment mechanism for bottle cover spacer assembly, include: the base, with base sliding fit's lift slider and drive the lifting drive mechanism of lift slider installs motor on the lift slider, by motor drive's quill shaft to and fix the hot pressboard in quill shaft bottom. The utility model discloses simple structure, convenient to use, through hot pressboard heating glue film, the glue film fixed line avoids the gasket to drop with higher speed to messenger's hot pressboard is rotatable, reduces the bulking thickness of glue film, promotes assembly quality.

Influence of nanoparticles on the surface discharge marks in oil-pressboard insulation

Abstract: It recently has shown that nanoparticles can improve the electric properties of transformer oil when it is added in the oil. This paper investigated the effects of nanoparticles on oil impregnated pressboard in terms of the surface discharge development, the surface tracking marks, and the material trapping properties. It is found that the nanoparticles can increase the shallow trap density in the oil impregnated pressboard, resulting in less carbonized tracking marks on the pressboard surface.