What is the lathe used for in the machining industry?

The lathe is one of the most widely used machine tools in the metalworking industry. Thanks to its versatility, the lathe has become a key piece of equipment for machining different materials, but it is also used for threading, cutting off, drilling holes, roughing, cylindrical turning and cutting grooves in workpieces of different materials. But do you know what the lathe is used for in the machining industry?

What is a lathe and how does it work?

Historically, it is believed that the (manual) lathe was invented in 850 BC in Egypt, but its use became very popular during the Industrial Revolution. It was during this period that the lathe began to be used for the rudimentary machining of metals; that is, during the Industrial Revolution the lathe was perfected so that it could shape metal parts, something we know today as machining.

The lathe works by rotating the workpiece to be machined, by means of revolutions, while it is held in a headstock. While the workpiece rotates, it comes into contact with one or more cutting tools that are pushed directly against the surface of the workpiece and advance along it. Machining by turning produces swarf, small metal strips.

But what is the lathe used for in the machining industry? Its applications are many, since it does not only machine through turning, but can shape workpieces through different processes (there are roughly eleven). These include, for example, cylindrical turning, drilling, grooving, parting off, knurling, facing, internal threading, external threading, boring, chamfering and taper turning. Each of these machining techniques has its own characteristics and, to carry them out accurately, a lathe operator or a CNC numerical control lathe is needed, which in turn also needs an operator to program the machine.

Benefits of machining workpieces on a lathe

Machining workpieces with a lathe as the machine tool brings great benefits to the metalworking industry. The main advantage is that the lathe can work on workpieces of different materials. On this machine you can work, for example, carbon steel, stainless steel, aluminium, copper, zinc, magnesium, titanium and so on.

The lathe also has the advantage that workpieces of different sizes can be machined on it and given different shapes. In addition, when lathes with numerical control (CNC) are used, the results are more accurate and have high-quality finishes.

Machining process on a lathe

Machining workpieces by turning also has the advantage of being a very simple process that does not demand great effort from operators, especially if the machine tool runs on CNC. The phases of the process are:

1. Set-up phase, where the workpiece is loaded and fixed in the lathe. The tool to be used for machining is also chosen and fitted, depending on the shape to be given to the workpiece. The duration of the set-up phase varies depending on the size of the workpiece to be worked.
2. In the second stage of the process, or cutting stage, the corresponding cuts are made on the workpiece with the chosen tool. During this phase, the workpiece turns on its own axis.
3. Traversing, or movement, phase, which is when the tool comes into contact with the workpiece as it turns on its own axis. This phase can also happen in reverse, when the process ends or when the tool needs to be replaced because it has worn.

Types of lathe most widely used for machining

In the metalworking industry there are different types of lathe suitable for machining workpieces. Each has its own particular characteristics, which should be studied before choosing one to include in a machine shop.

CNC or numerical control lathe

This type of lathe works through computer programming. First a design is created on the computer using CAD software which is then translated by CAM software and which is responsible for giving the lathe (via numerical control) the instructions for shaping the workpiece. It is one of the best types of lathe for machining workpieces.

Centre lathe

The centre lathe is characterised by metal cutting through movements in which the cutting tool is set directly against the workpiece as it turns on its own axis. This lathe allows cylindrical turning, drilling, threading and so on. But a skilled lathe operator is needed to use it.

Vertical lathe

The vertical lathe is the most recommended for machining large workpieces and is characterised by including CNC technology most of the time.