Machining Guide: What's Machining? Process Types, Tools, and Advantages

A material removal process in which a sharp cutting tool is used to mechanically cut away material so that the desired part geometry remains
•Most common application: to shape metal parts
•Machining is the most versatile and accurate of all manufacturing processes in its capability to produce a diversity of part geometries and geometric features
Casting can also produce a variety of shapes, but it lacks the precision and accuracy of machining.

What's Machining?

Machining is the broad term used to describe the removal of material from a workpiece. Includes Cutting,  Abrasive Processes (grinding),  Advanced Machining Processes (electrical, chemical,
thermal, hydrodynamic, lasers)

• Automation began when lathes were introduced in 1700s
• Now have computer numerical control (CNC) machines
• Machining operations are a system consisting of:
• Workpiece – material, properties, design, temperature
• Cutting tool – shape, material, coatings, condition
• Machine tool – design, stiffness & damping, structure
• Fixture – workpiece holding devices
• Cutting parameters – speed, feed, depth of cut

Material removal processes are often required after casting or forming to:

• Improve dimensional accuracy
• Produce external and internal geometric features, sharp corners, or flatness not possible with forming or shaping
• Obtain final dimensions and surfaces with finishing operations
• Obtain special surface characteristics or textures
• Provide the most economical means of producing a particular part

The Limitations, because material removal processes:

• Inevitably waste material
• Generally require more energy, capital, and labor than forming or shaping operations.
• Can have adverse effects on the surface quality and properties, unless carried out properly.
• Generally take longer than shaping a product with other processes.

What Are the Different Types of Machining Process?

Turning

A single point cutting tool removes material from a rotating workpiece to generate a cylindrical shape. Turning is performed on a machine tool called a lathe.

Boring

Difference between boring and turning:

• Boring is performed on the inside diameter of an existing hole
• Turning is performed on the outside diameter of an existing cylinder

In effect, boring is an internal turning operation.
Boring machines: Horizontal or vertical - refers to the orien

Drilling

• Creates a round hole in a work part
• This contrasts with boring which can only enlarge an existing hole
• The cutting tool called a drill or drill bit
• Customarily performed on a drill press

Milling

Milling operation in which work is fed past a rotating tool with multiple cutting edges.

• Axis of tool rotation is perpendicular to the feed direction
• Creates a planar surface
• Other geometries possible either by cutter path or shape
• •Other factors and terms:
  - Milling is an interrupted cutting operation
  - Cutting tool called a milling cutter, cutting edges called "teeth".
  - Milling tool called a milling machine

Different Tools Used in Different Types of Machining Processes

Turning tools: Lathe

In a turning tool operation, the workpiece rotates as the tool removes layers from it. The process is similar to boring but reconfigures the external surface of the workpiece instead of the center.

Boring tools:

Boring is the process of enlarging or expanding an existing hole by using a single point cutting tool. It may be used for workpieces that are too large to fit on a lathe or drill press. Standard boring equipment can bore holes up to 12 feet (3.6 m) in diameter.

Drilling tools:

Drilling removes material using a drill bit to cut a hole of circular cross section in the workpiece. It is the most common machining process, which is used about 75% of the time. A drill jig is placed into a chuck connected to a spindle, which is driven by a drill head powered by a pulley and electric motor. Either electronically or by hand, the drilling tool is lowered onto the surface of the workpiece.

Milling tools:

Milling produces three-dimensional shapes using a rotating multi-edge cutting tool. In CNC manufacturing, the milling tool can be programmed to move in several directions on a fixed workpiece. The process can create parts in a wide range of shapes with features such as slots, pockets, and grooves. There are several kinds of milling tools depending on the type of cuts required.

Machining Centers

Highly automated machine tool capable of performing multiple machining operations under CNC control in one setup with minimal human attention.

• Typical operations are milling and drilling
• Three, four, or five axes
• Other features:
  - Automatic tool-changing
  - Pallet shuttles
  - Automatic work part positioning

Milling-Turning Centers

A highly automated machine tool that can perform turning, milling, and drilling operations on a work part

• General configuration of a turning center
• Can position a cylindrical work part at a specified angle so a rotating cutting tool (e.g., milling cutter) can machine features into the outside surface of the part.
  - A conventional turning center cannot stop work part at a defined angular position and does not possess rotating tool spindles.

What Are The Advantages Of Machining?

1. Reliability
   The machining process takes place continuously without any breakdown despite the time or day of the week. The chips and the raw materials are converted into finished products and released into the market as high-quality tools. Breakdowns are very minimal as they may occur when maintenance is required or during a repair. Machines work reliably; it doesn’t matter whether it’s a weekday, weekend, or holiday.
2. Requires Less Human Labor
   Due to the development of technology, machining in manufacturing industries is automated. The process is mainly controlled by computers or robots that usually cut down production costs by eliminating human labor. During the controlled material addition, the process requires minimal supervision and oversight for maintenance purposes.
3. High Production
   The process brings about high productivity because they generally do a massive amount of work such as drilling, better surface finish, milling, and spinning in a relatively short period.
4. Identical Products
   The finished products, such as the cutting metals, are homogenous and have very little or no errors despite the high rate of production. As a result, the products become marketable due to their improved quality.
5. Increase Profit And Reduce Efforts
   Another great reason you need to machine your metal devices is to help increase profits and reduce efforts. Some people may wonder, how does machining relate to increased profits? The fact is that machining makes devices a little expensive, but it is, on the other hand, very beneficial. With a metal that has undergone machining, you will not only reduce the production cost, but it will also save much of your time and effort. Despite this advantage, it is always advisable if you want to purchase one, to be sure to check if the machine is right and whether it is error-free while working.
6. Improved Efficiency
   Machining is one of the best ways that can help increase the efficiency of your metals. When machining the metals, they are always fitted with internal quality assurance detectors. This brings along a lot of efficiency in terms of increasing the speed of production of the metals and ensuring good usage of raw materials. More to this, machining is always considered a remarkable way of ensuring high-level standards of metalworking and part fabrication. More to increase efficiency, machining is considered as one of the ways to cut down expenditure costs. This is due to its ability to drop the consumption cost; therefore, reducing money wastage. In short, it reduces expenditure; thus, adding to the benefits of carrying out the machining process.
7. Increased Accuracy
   Most of the metals that undergo machining are used in the manufacturing industries. This includes places that require manual turning and milling processes. They can also be used in the healthcare sector, but the point you need to note here, all these sectors involve a lot of accuracy. On this, they turn into metals that have undergone machining due to their accuracy level. This is clear evidence of how machining is essential in ensuring increased accuracy on your metals, which translates to accuracy in completing your tasks.

With our large-scale CNC machining capabilities, Openex is a premier provider of quality machined parts and fabrications. Serving the needs of clients from coast to coast, our facility is equipped with large swing lathes, heavy-duty CNC drills, and machining centers that allow us to manage workpieces with oversized dimensions and weighing up to 250 tons. We have a staff of technically skilled machinists noted for their fine quality workmanship and attention to detail on each machining project.

Contact us at sales3@openex.com.cn now for more information about our machining capabilities or a quote.