The diagrams reveals two stage processes of the cement production

The diagrams give information regarding to the process of cement production. In addition, how to produce concrete by the cement for constructing building has been plotted on the diagrams.

By and large, what stands out from the diagrams reveals that these data divides into two stage processes, namely cement and concrete production. While the former relies merely on two materials (limestone and clay), the latter need cement, sand, water and gravel.

To begin with, in the production of cement, limestone and clay are poured to a crusher. After being a powder, it is mixed in a small tube and flew into a bigger tube to be heated by fire. Afterwards the powder is sent to a grinder machine to change being cements. Finally, before this cement is used as a raw material to produce concrete, it is packed into bags.

Moving to the second stage from the diagrams represents that four materials, these are cement with 15 percent of the concrete proportion, water by 10 percent, sand by 25 percent and small stones by 50 percent as the highest proportion, are poured into concrete mixer. Then they are rotated by this machine. After this step, the material of concrete production is ready to be used for constructing a building.

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  this is the diagram.
  

The first diagram illustrates the process of cement production although the second picture gives a breakdown of information in term of how to produce concrete.


sorry to say, it is the weak overview. Overview mentions the general trend which can be obvious seen from the picture.

Let me try to write the overview paragraph.
It is noticeable that in cement production, there are five-tiered structures from crushing to packaging process. However, small stones are the highest proportion compared to other compositions which are required to produce concrete.