Vertical machining centres are, in themselves, one type of machining centre. Broadly speaking, there are two other types: horizontal centres and gantry-type centres. However, vertical centres are among the most widely used, given their many advantages, which has led to countless models tailored to every industrial need in factories and metalworking shops.
Today, the most common type of vertical centre is the CNC model (computer numerical control), which stands out for operating fully automatically: all it requires is the programming of codes corresponding to the coordinates the tool must follow to carry out the required machining operations on a given part.
General features of a vertical machining centre
As mentioned, vertical centres come in countless models, designed to meet many different machining needs in a variety of sectors (the automotive industry, for example). Nevertheless, the general features of each model are essentially the same:
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Vertical spindle |
The main feature is that the spindle head is located at the top of the machine and travels vertically. In other words, the workpiece is machined from above. |
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CNC automation |
On the outside of the machine there is a screen with cleverly designed buttons that make it easy to program numerical codes, coordinates or instructions, which are processed by a computer to perform the tool movements needed to achieve the desired result on the machined part. If the codes are programmed correctly, the margin for human error is practically eliminated, achieving pinpoint accuracy on the various surfaces of the part. |
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Multiple axes |
Increasingly advanced vertical centres continue to be developed, and there are now multi-axis models that can machine the workpiece from different angles, making it possible to produce more complex shapes and geometries. These axes can be located in the spindle head and/or on the worktable. |
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Liquid coolant system |
The high temperatures generated by friction between the tool and the workpiece are controlled by a liquid coolant system. The coolant is sprayed through nozzles aimed directly at the surface of the workpiece, which also helps clear away the chips produced. |
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Multi-tool turret |
The latest models also feature automated systems that allow the vertical centre to change tools by itself. There are two common systems: one in which a robotic arm removes a tool from the spindle head and inserts another, and one in which the turret has multiple holders (each with a tool already mounted) on a kind of rotating disc. |
With regard to this last feature, it is worth noting that these machine tools can perform multiple functions, not only the traditional one of milling. For example, they can also work as a vertical drill-tap centre or as a vertical drilling centre. It all depends on the tool used for each task.
Advantages of using a vertical machining centre
The various types of vertical centre offer many advantages when machining parts, especially metal parts, which are difficult and very time-consuming to shape using conventional methods. In fact, shorter lead times and simpler processes are two of the main advantages of vertical centres. There are other equally notable benefits:
- They maximise output at mass-production scale.
- They improve the financial performance of the factory or workshop where they are used.
- Several vertical centres can be set up in line, supervised by one or very few operators.
- They reduce costs in labour and operators.
- They deliver extremely precise results, leaving surfaces smooth and free of imperfections.
- Series production is more precise and consistent across all units manufactured.
- The workpiece is machined from above, allowing the operator to see the process more easily and compare the results with the design.
- Once the codes needed for the different parts and machining movements used in a workshop have been programmed, they simply need to be swapped whenever required.
- Automatic tool changing greatly reduces production times, as well as the likelihood of human error.
It should be noted that these machine tools do have certain “disadvantages”, although the financial benefit in the medium and long term more than compensates for them. The most notable are their high initial cost and the cost of maintenance and replacement parts, which is also considerable.