Process of pencil

It is divided into two parts: pencil cap and pencil rod: the appearance decoration material of pencil cap is mainly polyester material, and the manufacturing process can be divided into molding, offset printing, assembly and other processes. The appearance decoration materials of pencil rod mainly include nitrofiber pencil paint, printing ink, electrochemical aluminum foil, rubber head and aluminum hoop. The manufacturing process can be divided into pencil board, lead core, pencil rod, finished product decoration and other processes.

In pencil board processing, the log is disintegrated and cut off, cut into wood blocks by square sawing, and cut into pencil boards by board cutting machine after hydrothermal treatment. The plate is 184mm long, 73mm wide and 4.8 ~ 5.2mm thick. After heating (60 ~ 120 ℃) drying and high temperature (130 ~ 200 ℃) denaturation treatment, the pencil board is softened and easy to curl.

Lead core processing graphite lead core is prepared by mixing graphite and clay in a certain proportion, mixing by kneading machine and three roller machine, extruding lead core with a certain specification and size (such as HB ~ 3H lead core diameter of 1.80 ~ 2.10mm) through core pressing machine, heating (50 ~ 150 ℃) drying and high temperature (800 ~ 1100 ℃) roasting to make it have certain mechanical strength and hardness, and finally oil immersion treatment. The color of lead core is similar to that of graphite lead core, but sintering is not required. There are two processing methods: one is to mix clay, talc powder, adhesive, pigment, grease and wax evenly, and then form and dry them, which is called mixing method; The other is made by mixing porcelain clay, talc powder, pigment and adhesive evenly and extruding them into lead core, or putting the dried lead core in the oil core container to fully absorb grease at a certain temperature, which is called oil immersion method.

For the processing of pencil rod, the pencil plate is planed into a groove plate with a thickness of 4.1 ~ 4.2mm and a core groove corresponding to the diameter of the lead core, then the lead core and the pencil plate are glued with adhesive, heated in the clamped state (50 ~ 120 ℃) and dried for 1 ~ 8 hours, and the white rod pencil with a length of 178 ~ 180mm is processed by the rod planer.

For appearance decoration processing, the white pencil will be painted and printed for decoration, as well as polished, printed trademarks, rubber heads and caps, so as to make it a finished pencil with certain specifications, appearance colors and patterns.