Let's change the topic here and look into material cleaning, which will be processed as part of the surface treatment of metal products.
In general, the surface treatment will be performed in the following steps:

Before performing surface treatment such as plating work, the pretreatment process is always required since plating work cannot be applied directly to the product surface.This step is called the pretreatment process of plating, which prepares the surface of the plating substrate for plating.In other words, this is a process for cleaning the substrate surface (including plastic and ceramic materials in addition to metal products in recent years.)The pretreatment process starts with the removal of various dirt and grime attached to the substrate surface in order to expose the surface.This task is referred to as "cleaning."
Now, let's see what kind of dirt and grime we will found on the substrate surface.

Grime on Metal Surfaces -1

Before moving onto the topic of metal cleaning, let's take a look at surface grime.In general, any the following types of dirt and grime can be attached to the surface of metal products to be processed for surface treatment:

(1) Antirust/lubrication oil

Storing finished metal products without any other processing will cause the products to develop rust or generate discoloration due to oxidation. These changes damage the product and interfere with the subsequent processing.To prevent such phenomena, it is common to apply an antirust coating before storing the products.As the antirust coating, apply petroleum-derived or animal/vegetable antirust oil onto the product surface.

(2) Lubrication oil for metal-forming process

Metal materials are formed into metal products after going through various metallic processes as listed below.During processing, many types of lubricants and coolants are used to facilitate the processing and to prevent wear by reducing friction between products and molds/tools while minimizing heat generation.