Pencil making process

It is divided into two parts: a pencil cap and a pencil rod: the material for the appearance decoration of the pencil cap is mainly polyester material, and the production process can be divided into processes such as mold making, offset printing, and assembly to complete it. The decorative materials for the appearance of pencil rod mainly include nitrocellulose pencil paint, printing ink, anodized aluminum foil, rubber head and aluminum hoop. The manufacturing process can be divided into pencil board, lead, pencil rod, finished product decoration and other processes.

The processing of the pencil board breaks and cuts the logs, and the square saw is broken into pieces of wood. After hydrothermal treatment, it is cut into a pencil board by a board cutting machine. The board 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 made up of graphite and clay in a certain proportion. After being kneaded by a kneading machine and a three-roller, a certain size is extruded by the core pressing machine (such as HB～3H lead core diameter is 1.80～ 2.10mm) lead core, dried by heating (50～150℃) and roasted at high temperature (800～1100℃) to make it have certain mechanical strength and hardness, and finally made by oil immersion treatment. The processing of color lead is similar to that of graphite lead, but no sintering is required. There are two processing methods: one is to mix clay, talcum powder, adhesive, color, grease and wax, etc., and then make it by molding and drying, which is called mixing method; the other is to mix porcelain clay and talc powder. , Pigments and adhesives are mixed evenly and extruded into lead cores or put the dried lead cores in an oil core container to make it fully absorb grease at a certain temperature. It is called oil immersion method.

In the processing of pencil rods, a planer is used to plan the pencil board to a thickness of 4.1 to 4.2 mm, and a slot board with a core slot suitable for the diameter of the lead core. Then, the lead core and the pencil board are glued together using a glue. After heating (50-120°C) and drying for 1 to 8 hours in a tight state, it is processed by a bar planer to make a white bar pencil with a length of 178 to 180 mm.

Appearance decoration processing The white rod pencil is decorated with paint and printing, as well as cutting, printing trademarks, rubber heads, caps, etc., making it a finished pencil with certain specifications, appearance colors and patterns.