Production technology of pencil

The production process flow chart of pencil is as follows:

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Cored-after gluing, put the graphite core in the groove to cover the board-cover and bond the upper (grooved) board and the lower board-completely bond and separate the upper and lower boards with a pressure of one ton-cut the bonded board into pencil shapes for inspection-test the hardness and other qualities of the pencil.

2. Spray painting-spray painting and roll printing the appearance of the pencil according to the required color-print letters and characters on the pen body for assembly-assemble the rubber head on the pencil.

3. Grinding-grinding the pencil tip and waiting for delivery.

The main components of pencil refill are graphite and clay. Graphite is a scaly solid with metallic luster, in which there are carbon-carbon chemical bonds and van der Waals force is between layers. Carbon-carbon chemical bonds are very stable and difficult to break.

This is why both diamonds and graphite are made of carbon, but their physical properties and prices are quite different. Nothing in the human body can break the carbon-carbon chemical bond, so it is certain that pencil lead is safe (unless the clay added in it is harmful to human health).