Abstract: A transformer bushing partial discharge monitoring chip device and method are provided. An acquisition unit comprises three sensor modules installed at end screens of three-phase bushings of a transformer respectively for acquiring partial discharge signals and power frequency current signals from the transformer bushing end screens; each of the sensor modules is connected to an SIP digitization unit through a wire; the SIP digitization unit is fixedly installed beneath a base of the acquisition unit for digitizing the partial discharge signals and the power frequency current signals; an output end of the SIP digitization unit is connected to an input end of a background processing terminal.

Abstract: A pressure relief apparatus may include a pressure relief portion and a plurality of stages of indented grooves. The pressure relief portion may be provided with a first surface and a second surface arranged opposite to each other in a thickness direction thereof. The plurality of stages of indented grooves may be formed in the pressure relief portion in sequence in a direction from the first surface to the second surface, and among two adjacent stages of indented grooves, the stage of indented groove away from the first surface may be formed in a bottom surface of the stage of indented groove close to the first surface. The pressure relief portion may be provided with an opening area, and the indented grooves may be formed along an edge of the opening area.

Abstract: The invention discloses an acrylic acid-modified epoxy polyester resin and the preparation process thereof. The resin comprises 100 pbw of a copolymer (A) formed from an unsaturated fatty acid-modified polyester and a bisphenol A type epoxy resin, and 20-40 pbw of poly(meth)acrylic acid (ester) (B). The preparation process comprises the following steps: (1) alcoholyzing a drying oil with a polyol; (2) adding successively, to the product from step (1), a dibasic anhydride, a fatty acid containing a conjugated double bond and an epoxy resin, and esterifying to obtain an epoxy polyester; and (3) copolymerizing the epoxy polyester from step (2) and an acrylic monomer. This invention also provides a water-based emulsion containing said resin, and a water-based paint exhibiting excellent antirust property and having low production cost.

Abstract: The invention discloses an acrylic acid-modified epoxy polyester resin and the preparation process thereof. The resin comprises 100 pbw of a copolymer (A) formed from an unsaturated fatty acid-modified polyester and a bisphenol A type epoxy resin, and 20-40 pbw of poly(meth)acrylic acid (ester) (B). The preparation process comprises the following steps: (1) alcoholyzing a drying oil with a polyol; (2) adding successively, to the product from step (1), a dibasic anhydride, a fatty acid containing a conjugated double bond and an epoxy resin, and esterifying to obtain an epoxy polyester; and (3) copolymerizing the epoxy polyester from step (2) and an acrylic monomer. This invention also provides a water-based emulsion containing said resin, and a water-based paint exhibiting excellent antirust property and having low production cost.