Why Coolants and Lubricants Are Needed for Cutting？
The use of coolants and lubricants in metalworking is extremely important. That’s why we analyze cooling and lubrication in this article.
If you need to drill a lot of holes, or want to achieve good hole quality when drilling, not only do you need to choose the right drill bit, but you also need to consider cooling and lubrication. If you don’t use the right cooling lubricant, you may have a bad experience.
But before we get to the right cooling lubricant, let’s see what happens during the cutting process.
How Does Friction Between Two Materials Occur?
Why do we need cooling and lubrication? Let’s assume you are drilling a hole with a twist drill. The rotary motion of the twist drill and the resulting friction with the workpiece generates heat. In some cases, application temperatures can reach up to 1200°C. Cooling is very important, for example, to prevent heat from making the twist drill brittle (annealing).
However, there are other reasons why you should use coolants and lubricants.
Uses of Coolants and Lubricants
Cooling and lubrication in metalworking have different purposes and are therefore very important:
- Reducing friction between the drill bit and the workpiece
This reduces wear on the drill bit and therefore extends tool life
- Dissipation of heat, cooling
Dissipate heat as quickly as possible to prevent the tool and workpiece from overheating.
- remove chips and minimize wear, facilitate chip flushing and chip removal
- cleaning the workpiece and protecting the workpiece against corrosion
- Improvement of the surface of the workpiece Quality of the workpiece is ensured
What Kind of Cool Lubricant for What Kind of Process？
But which coolant do you use in your application? First, you must understand the cutting process.
Then, choosing the right cooling lubricant depends on the cutting speed, the workpiece to be cut, and the cooling and lubricating effect desired.
Choose different cutting concentrates depending on the application. Coolants and lubricants are available as cutting pastes, cutting sprays and general-purpose cutting oil concentrates.
The choice of cooling lubricant depends on:
- the drilling process (drilling, countersinking, thread cutting), and the requirements for cooling, flushing and lubrication
- the cutting capacity of the workpiece
- the cutting speed
- the required dimensional accuracy and surface quality to be achieved
- the thermal sensitivity of the material to be machined.
If you take these factors into account, consult the following table to choose the appropriate coolant and lubricant.
Cutting & Cooling Table
| Cutting type | Cutting speed | Cooling effect | Lubrication effect | Coolants & lubricants |
|---|---|---|---|---|
| Pre-drilling | Very high | Very high | Very low | Spray water‐soluble cooling lubricants |
| Drilling | Very high | Very high | Very low | Spray water‐soluble cooling lubricants |
| Countersinking | Medium | Medium | High | Non‐aqueous lubricants (oils & pastes) |
| Threading | Very low | Very low | Very high | Non‐aqueous cutting fluids (oils & pastes) |
Conclusion
You should apply cooling when cutting steel and metal whenever possible.
5 important reasons to use cooling lubrication:.
- Reduce friction between the drill and the workpiece
- cools down and removes heat
- to remove chips and reduce wear
- workpiece cleaning and rust prevention
- Improvement of the surface quality of the workpiece
By choosing the right coolant and lubricant for each application, you can strive for good holemaking results.