Material preparation equipment is the equipment for pretreatment and processing of papermaking raw materials before cooking or refining according to the requirements of cooking or refining process. It is divided into non wood fiber material preparation equipment and wood fiber material preparation equipment. The former includes grass cutter, reed cutter and sugarcane pulp remover, while the latter includes peeler and chipper. Chipper is a kind of machine which can cut the logs required for producing wood pulp into chips of a certain specification, which is divided into disc type and drum type; digester is a kind of equipment which can dissolve the lignin in the paper-making raw materials in the cooking liquid and separate the paper-making raw materials into fibers, which is divided into intermittent type and continuous type; wood grinder is a kind of equipment for producing wood pulp, which can be divided into intermittent type and continuous type according to the mode of production There are two kinds of pressurized methods: hydraulic pressurized and mechanical pressurized; pulping equipment is used in the process of separating plant raw materials into fibers. Pulping methods can be divided into chemical method, mechanical method and chemical mechanical method. The corresponding pulping equipment includes digester, wood grinder, hot mill, pulp washer, pulp bleaching machine, beater and waste liquid recovery equipment. Wood chips are heated by steam and then ground under high pressure. The machine for making hot wood chips is hot mill, which consumes a lot of power. Therefore, making full use of the heat energy in the process of grinding is the key problem of hot mill. Pulp washer is the mechanical equipment for separating the pulp from black liquor. According to the extraction rate of black liquor, it has high concentration And low concentration extraction. The purpose of pulp bleaching is to remove the residual lignin and pigment in the pulp after cooking, improve the purity of pulp and make the pulp have white color. Bleaching machine is a kind of bleaching equipment which is widely used. It is composed of screw propeller of bleaching tank and washing drum. Pulp and bleach are put in the tank and washing water is added continuously. With the help of screw propeller, they circulate in the tank and complete the process of mixing and chemical reaction. The water with bleach products and residual bleach liquor is discharged through the inner cavity of the washing drum to obtain white pulp. The paper machine is a complete set of equipment to make the pulp form the web, including headbox, net part, press part, dryer, calender, Winder, transmission part and other main machines, as well as steam, water, vacuum, lubrication, heat recovery and other auxiliary systems. The web forming the wet web is the core of the paper machine, so the paper machine can be divided into long web paper machine, pinch web paper machine and round web paper machine according to the web structure. Headbox is a kind of equipment which can send the pulp of appropriate concentration to the net evenly and stably through the distributor, rectifying device, weir pool, weir plate nozzle and other parts, also known as the net front box. After the pulp is sprayed from headbox to the copper net, the wet paper is formed on the net and dehydrated. Then it is pressed, that is, the moisture of the wet paper is extruded from the net by mechanical method to improve the dryness of the paper At the same time, it can improve the surface properties of the paper, eliminate the net mark and increase the smoothness, tightness and strength; then it can enter the drying section to further dehydrate the wet paper after being pressed, and the paper machine uses the dryer cast iron dryer pressure roller to shrink the paper, make the fiber bond tightly and increase the strength. After calendered by calender, the smoothness, glossiness and compactness of the paper sheet can be improved, the thickness of the whole sheet can be consistent, and the air permeability can be reduced; at least, the paper sheet can be rolled into a paper roll by the winder, which completes the main process of papermaking. In order to meet the different needs in the future, there are also super calender, rewinder, paper cutter and so on behind the winder in the paper workshop. Paper industry will consume a lot of raw materials, water, electricity and chemicals, and produce a lot of wastewater and waste residue. Therefore, the future of papermaking machinery will be to use a wide range of papermaking raw materials, reduce the consumption of materials and energy in the papermaking process, and reduce environmental pollution.