TYPES OF CNC MACHINES
All the modern CNC machines are completely electronic while more industrial activities such as ultrasonic welding, hole-punching, laser cutting, etc. have been included in the system.
The early industrial machines used in the 1940s make use of the analog control methods for their operations, leading to a high rate of material wastage, non-uniformity of parts, and other defects.
There are many types of CNC machines currently available for industrial applications. However, few of them have been highlighted here based on their popularity and dominance in the engineering field.
Here are the major types of modern CNC machines:
CNC MILLS
These are machines used in milling operations of metals and other solid materials in the industry. They are capable of running on programs comprised of the number and letter-based prompts that guide pieces across various distances.
The programming employed for mill machines could be based on either G-code or some unique language developed by a manufacturing team.
They consist of a 3-axis system which are X, Y, and Z while some new ones may have more than just the 3-axis system.
CNC LATHES
With CNC technology, a lathe machine can cut pieces in a circular direction with indexable tools.
The cuts employed in this way may be carried out with precision and high velocity.
The machine can be used to produce complex designs that wouldn’t be possible on manual operations.
The same control functions that work for CNC mills may work for CNC lathes, such reveals the similarities between the two machines.
The lathe can be directed by G-code or unique proprietary code. Most of the CNC lathes consist of two axes -X and Z.
ELECTRIC DISCHARGE MACHINES (EDM)
They are referred to as die sinking and spark machining. It is a process that molds workpieces into particular shapes with electrical sparks.
With the machine, current discharges occur between two electrodes, and this removes sections of a given workpiece.
When the space between the electrodes becomes smaller, the electric field becomes more intense and thus stronger than the dielectric.
This makes it possible for a current to pass between the two electrodes. Consequently, portions of a workpiece are removed by each electrode.
The subtypes of EDM include:
Wire EDM, whereby spark erosion is used to remove portions from an electronically conductive material.
Sinker EDM, where an electrode and workpiece are soaked in dielectric fluid for the purpose of piece formation.
In a process known as flushing, debris from each finished workpiece is carried away by a liquid dielectric which appears once the current between the two electrodes has stopped and is meant to eliminate any further charges.
PLASMA CUTTERS
In this CNC machine, a material is cut with a plasma torch. It is a process that is foremost applied to metal materials but can also be employed on other surfaces.
In the process, plasma is generated through a combination of compressed air gas and electrical arcs in order to produce the speed and heat necessary to cut metal.
WATER JET CUTTERS
Water jets are tools that cut hard materials like granite and metal with high-pressure applications of water. In some cases, the water is mixed with sand or other strong substance. It is a process used often for the shaping of industrial machine parts.
For materials that could not bear the heat-intensive processes of the CNC machines, water jets are employed as a cooler alternative.
With that application, it has gained relevance in a wide range of sectors such as the aerospace and mining industries.
It is the most suitable for the carving and cutting of hard materials with high thermal conductivity.
Besides the above-explained CNC machines, others that are not popular in industrial applications are:
- Glass cutters
- Cylindrical grinders
- Turret punchers
- Wire-bending machine
- Laser cutters
- Embroidery machine
- 3D printers
- Wood routers
- Foam cutters
And others.
