Rolling is a metal forming process in which the deformation takes place under the application of Compressive forces between the rollers. In this article, we are going to discuss a detailed presentation on the Rolling Process with its Principle, Working, Types of Rolling Mills, Advantages, Disadvantages & Applications.
Let's dive into the article of Rolling Process...
The rolling is one of the metal forming processes in which the material (metal strip) is compressed in between the two or more rotating rollers such that the stress responsible for changing the shapes of the material is only by compressive stress.
This process reduces the actual thickness to the desired thickness.
Rolling is classified into two types according to the temperature of the metal being rolled. One is the hot rolling and the other is cold rolling.
If the temperature of the metal is above the recrystallization temperature, then the process is known as hot rolling.
If the temperature of the metal is below the recrystallization temperature during rolling, then the process is known as cold rolling.
The basic diagram of Rolling is shown below.
In Rolling operation, the metal strip or the material is to be placed in between two rollers such that material is compressed by the opposite forces of the rollers to make the material to a uniform thickness.
The presence of friction between rollers and the strip is making it pull the strip into the rollers without applying any pulling and pushing.
By the application of rolling, the length of the material increases and thickness reduces without any change in the width of the workpiece.
Does anyone know, how we get a uniform thickness of the workpiece by Rolling Process?
During rolling, there might be a chance that the workpiece can bend due to the unequal compression on the different parts of the material and this can be solved as follows.
To avoid the bending of the strip during rolling, the surface velocity of both the rollers must be equal.
I.e. Vtop roller = Vbottom roller
=>(πDN) top roller= (πDN)bottom roller
=>(DN) top roller= (DN)bottom roller
If D top= D bottom =>Nt = N [Here D top=Dia of Top Roller & D bottom = Dia of bottom Roller]
Therefore Nt = Nb.
To ensure that the contact area between the rollers and the strip at both sides, the dia of both sides must be the same. hence the speed of both the rollers will also be the same.
If one roller is rotating with N speed and the other is rotating with N1 speed, then we will get incomplete compression of the roller.
Therefore, it is recommended to use the same speed for both the rollers.
Metal Rolling is classified into 5 types and they are as follows.
A detailed explanation for the Types of Rolling Mills is as follows.
The diagram for the rest of the rolling mills is shown below.
This is the detailed explanation on are different types of rolling mills.
The advantages of Rolling process are as follows.
The disadvantages of Rolling process are as follows.
The applications of Rolling process are as follows.
This is a detailed explanation of the Rolling Process. If you have any doubt, feel free to ask in the comments section.
The rolling is one of the metal forming processes in which the material (metal strip) is compressed in between the two or more rotating rollers such that the stress responsible for changing the shapes of the material is only by compressive stress.
There are two types of Rolling Process. One is the hot rolling and the other is the cold rolling process
These are the types of Rolling Mills:
1. Two High Rolling Mills
2. Three High Rolling Mills
3. Four High Rolling Mills
4. Cluster Rolling Mills
5. Tandem Rolling Mills
By rolling process, Large length cross sections are produced.