Have you ever thought why liquid is sprayed during a cutting operation? Don’t worry! In this article we will dive into the detailed explanation of cutting fluids. Let’s begin with the definition of cutting fluid.
What is Cutting Fluid?
Cutting fluid also called as Coolant or lubricant is used for improving the cutting condition as well as the life of the tool. It can be in liquid as well as gaseous form.
Purpose of Cutting Fluid
The cutting fluid or coolant is used for various purposes, some of them are listed below:
Used to Cool the Tool
With the help of cutting fluid, we can decrease the friction between the tool and the workpiece. Also, we can minimize the heat during the cutting operation. By doing this we see an increase in tool life. Also we get a good surface finish and we can prevent metallurgical damage.
Used for Lubrication
It is used for lubricating purposes. This helps the cutting fluid to chip easily and can be removed from the workpiece.
Used to Decrease Friction
Coolant is used to decrease friction. By doing this we can restrict the heat generation. Hence less power is consumed that increases the tool’s life.
Restrict Thermal Distortion
By using cutting fluid we can restrict the change of properties of the material because of heat.
Used as Cleaner
Coolant or cutting fluid is used as a washing agent. With the help of cutting fluid, we can clear the operation area if there is dust inside the cutting area that results in uneven cutting that’s why we need to clean the cutting area.
Some Other Benefits of Using Cutting Fluid
- It is used to get a good surface finish.
- It reduces the tool wear.
Properties of Cutting Fluid
The following are the properties of Cutting Fluid:
- A cutting fluid has a low viscosity so that it can easily flow above the workpiece.
- It should have a high flash point so that it can be used at high temperatures.
- It should be stable at high temperatures.
- It should have a non-foaming tendency.
- It should have a high heat absorption rate so that during cutting operation it can easily absorb the generated heat.
- It should have a good lubricating property to reduce the friction between tool and workpiece so that chips can easily get out from the workpiece.
- Coolant should not react chemically, it has to be chemically active in nature.
- It should be odorless to avoid any bad smell even at higher temperatures.
- It should be transparent so that the operator can easily see the cutting area.
- It should be harmless to the operator.
Types of Cutting Fluid
Following are the main types of cutting fluid :
- Soluble Oil
- Cutting oil
- Synthetic Coolants
- Solid Lubricants
Soluble oil is a mixture of water, mineral oil, and coupling agents. Generally, we use soap as a coupling agent. Insoluble oil, an emulsion of mineral oil in water is used at the ratio of 1:10 to 1:100 depending on the operation we are performing. In Lathe operation, drilling operation, shaping operation we use this type of cutting fluid.
It is a mixture of mineral oil and fatty oil. It is mainly used in hand-cutting machinery. It can be used as a coolant as well as a lubricant for Low cutting and high cutting rates respectively.
As the name suggests, it contains zero mineral oil, it has a higher cooling rate. Generally, this type of coolant is used in grinding operations.
Solid lubricant means it is in the solid phase, soap bars, molybdenum disulfide, graphite, and the wax stick can be used as a solid lubricants.
Cutting Fluid Applications
Cutting fluid can be used in different purposes which are as follows:
- As a Coolant
- Used to cool the cutting tool, chip, and job.
- As a Lubricant
- Used for easier movement of the tool on the job and also reduces the cutting force.
- Used as Lubricant and Coolant
- Cutting fluid can also be used for coolant and lubrication purposes like Fatty Oil.
- As a Flashing Action
- To wash off chips, to get a better surface finish
Selection of Cutting Fluid
- The selection of Cutting fluid mainly depends on the job material along with tool material.
- It also depends on which kind of operation do you want to perform.
- And last but not least it depends on the cooling effect.
Here’s a list of material along with the cutting fluid you should use on these materials:
|CI, Brass||Dry Fluid|
|Steel||Cutting oil or Cutting compound|
|High speed steel||waterless cutting fluids|
|Hard Steel, Bronze||Mineral Oil|
A Detailed Video on Cutting Fluid
Cutting Fluid FAQ’s
We use cutting fluids to minimize the heat generation rate and also for lubrication purposes.
We can categorize a cutting fluid into 4 types which are as follows:
1. Soluble Oil
2. Cutting oil
3. Synthetic Coolants
4. Solid Lubricants
Yes, a coolant can be used as a lubricant for metal cutting purposes.
I hope you are clear about cutting fluids and their types. If you have any questions, feel free to ask in comments.