Milling machines facilitate in removing metal pieces through a rotating cutter. The rotation of the cutter takes place at high speed, which helps it cut through metal efficiently. Furthermore, these cutters have cutting edges that play a vital role in cutting materials.
Milling machines can hold more than one cutter at a time. It is the most important machine that you can find in a workshop. You can perform operations with high accuracy. It has a high rate of metal removal compared to other similar machines, such as a shaper, planner, and lathe machines.
These machines are famous for their better surface finishing and excellent accuracy, making them a necessity for production work. Milling machines are available in many types. Some of the main types of milling machines are as under:
Knee and Column Type
The most common type of milling machine is called knee and column. In this machine, you will find a vertical column that is attached to the bed that consists of all the gear drives and helps in rotating the knee and saddle. The knee in a knee type milling machine is responsible for providing vertical or up and down movement to the workpiece which is located in the base of the machines. In the upper region of the knee, you will find a saddle attached. The saddle can move in a transverse direction.
1. Horizontal or Plain Milling Machine
Plain milling machines are more robust than hand millers. The plain milling machines that have a horizontal spindle are also called horizontal milling machines. You can feed the table in vertical, cross, or horizontal directions. The feed includes:
- Verticle – adjusts the table vertically.
- Cross – moves the table parallel to the spindle.
- Longitudinal – rotates the table
2. Vertical Milling Machine
The position of the spindle on a vertical milling machine is perpendicular or vertical to the table. You can use this machine for slots, machining grooves, and flat surfaces. The spindle head is fixed to a vertical column, which rotates at an angle. The milling cutter is fixed on the spindle to work with angular surfaces. In some vertical milling machines, you can adjust the spindle up and down.
3. Universal Milling Machine
Universal milling machines can adapt to perform a wide range of operations. The table can pivot at any angle for up to 45-degrees on both sides from the normal position. As the table of the horizontal milling machine can move in three directions, it also boasts the fourth movement. This machine can also perform helical milling operations. You can also use additional attachments to increase the capacity of the machine. Some special attachments include:
- Slotting attachment
- Rotary attachment
- Vertical milling attachment
- Index head or dividing head
You can produce a milling cutter, reamer, twist drill, spiral, bevel, spur, and much more from this machine. You can perform all the operations that a shaper machine does with the universal milling machine.
Fixed Bed Type or Manufacturing Type
A fixed bed type, as its name hints, is a type of milling machine that has a rigid bed attached to the machine. You cannot arrange the saddle and knee of this milling machine. It has a movable spindle head-mounted with the spindle of the machine. The machine can perform cutting operations by moving in horizontal and vertical directions.
1. Simplex Milling Machine
The spindle or the spindle head can travel in one direction only. The most common direction in which it can move is vertical.
2. Duplex Milling Machine
The spindle can move in both horizontal and vertical directions.
3. Triplex Milling Machine
The spindle can move in all three directions i.e. X Y and Z axis.
Planer Type Milling Machine
These machines are also called “plano millers.” A planer type milling machine performs heavy-duty tasks and is massive in sze. This machine contains spindle heads that are adjustable in transverse and vertical directions.
The Planer type machine relates to a planer and is similar to the planning machine. The cross rails of these machines can lower and raise the cutters. Their saddles and heads are all supported and maintained by rigid uprights.
The vital difference between a plano miller and a planer is the movement of the table. In a planer, the cutting speed increases through the movement of the table, whereas in the plano miller, the table moves to give the feed.
These are unusual milling machines and perform special tasks that other milling machines don’t. The special type machines consist of a spindle to rotate the cutter and have a provision for moving the workpiece or the tool in different directions. Here are some of the special type milling machines that are common:
1. Rotary Table Milling Machine
The rotary table milling machine consists of a circular table that rotates in a vertical axis. You need to set multiple cutters at different heights. The machine works with one cutter roughing up the workpiece, and the rest of the cutters finishing the surface. The operator can load and unload the workpieces continuously while the machine is working, and that is the most significant advantage of the rotary table milling machine.
2. Tracer Controlled Milling Machine
This machine is perfect for tracing the elements and reproducing dies with complex and irregular shapes. The stylus energizes the oil relay system, operating the primary hydraulic system of the table. This type of arrangement is called servomechanism and is complicated.
3. CNC Milling Machine
The most versatile milling machine is the CNC machine, and you have to control its operations using a computer. In this machine, the spindle can travel in all three directions, and the table rotates 360 degrees. The features of these machines are similar to bed type milling machines, so we can consider the former an upgraded version of the bed type. The movements are controlled hydraulically on commands through a computer. You simply load the sketch of the workpiece into your computer, and it automatically cuts the workpiece through its cutters based on that sketch.
4. Drum Milling Machine
The drum milling machine is just like a rotary table. The only difference is that this machine has a table that supports the workpiece and is called a drum, which can only rotate horizontally. To remove the metal, you need to place the workpiece on the drum. These cutters have three or four spindle heads. After one complete turn, you need to remove the finished parts and clamp the new one onto it.
Now you know the main types of milling machines that you will find in almost every industrial sector for cutting materials and shaping them. The next step is to pick a machinery company that listens to you, understands your requirements, and delivers the best solution to you in the form of a machine that lasts for years and requires minimal maintenance. If you are looking for a reliable partner for all your mechanical needs, WMW Machinery can definitely help.