The following diagram shows how pencils are manufactured write a university lecture

This pictorial diagram illustrates the manufacturing steps of a pencil. As can be clearly noticed, it consists of performing several processing steps on raw materials that will finally turn them into the final product.

Having analyzed the given diagram, we observe that mixing the ‘ground graphite’, clay and water will form graphite dough; afterwards, Going to the ‘forming press’ machine, graphite dough transforms to long rods. Shortly after these rods should be sized to equal pieces; however, they still need to get dry by going to an 800 degrees oven. At this point pencil leads are ready. Concurrent to previous operation, lumbers are sliced to slats; moreover, grooves are carved out on them. Gluing the ready leads on the grooves will result in what is known as the ‘sandwich’ of slats; afterwards, entering the ‘shaping machine’ ‘sandwich’ of slats will turn into the smooth finished pencils as the finished products.

Generally speaking we can say that this process is consist of two parallel sub processes to make the leads and the cases and a final linear process to fit those together.