This article refers to the address: http:// The plastic bag sealing machine described in this paper can be used for sealing plastic bags of cakes, candy, Chinese and Western medicines and electronic components. It has the characteristics of high efficiency, fast sealing and good sealing quality, and can seal plastic bags of different thicknesses. The whole line consists of a rectification delay circuit , an electric heating and a work indicating circuit, and all the parts can be housed in a wooden box.