Advantages of CNC machine - Reverse Engineering

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 Advantages of CNC machine

Advantages of CNC machine

        As the manufacturing sector develops, there is lots of research done in automation, and CNC machines are one of the best examples of automation and industry 4.0. because they have lots of advantages compared to old methods. Industries like aerospace, automobiles, manufacturing, etc. require a high level of precision; hence, CNC machines play a leading role in the development of the mechanical industry.

What are the main advantages of numerical control?

• It is important to know which areas of machining will benefit from it and which are better done the conventional way. It is absurd to think that a two horse power CNC mill will win over jobs that are currently done on a twenty times more powerful manual mill. Equally unreasonable are expectations of great improvements in cutting speeds and feed rates over a conventional machine. If the machining and tooling conditions are the same, the cutting time will be very close in both cases.

Some of the major areas where the CNC user can and should expect improvement:

1. Setup time reduction
2. Lead time reduction
3. Accuracy and repeatability
4. Contouring of complex shapes
5. Simplified tooling and work holding
6. Consistent cutting time
7. General productivity increase

• Each area offers only a potential improvement. Individual users will experience different levels of actual improvement, depending on the product manufactured on-site, the CNC machine used, the setup methods, complexity of fixturing, quality of cutting tools, management philosophy and engineering design, experience level of the workforce individual attitudes, etc.

Setup time reduction:

• In many cases, the setup time for a CNC machine can he reduced, sometimes quite dramatically. It is important to realize that setup is a manual operation, greatly dependent on the performance of CNC operator, the type of fixturing and general practices of the machine shop. Setup time is unproductive, but necessary it is a part of the overhead costs of doing business. To keep the setup time to a mini- mum should be one of the primary considerations of any machine shop supervisor, programmer and operator.

• Because of the design of CNC machines, the setup time should not be a major problem. Modular fixturing, standard tooling, fixed locators, automatic tool changing, pallets and other advanced features, make the setup time more efficient than a comparable setup of a conventional machine. With a good knowledge of modern manufacturing, productivity can be increased significantly.

Lead time reduction:

• Once a part program is written and proven, it is ready to be used again in the future, even at a short notice. Although the lead time for the first run is usually longer, it is virtually nil for any subsequent run. Even if an engineering change of the part design requires the program to be modified, it can be done usually quickly, reducing the lead time. Long lead time, required to design and manufacture several special fixtures for conventional machines, can often be reduced by preparing a part program and the use of simplified fixturing.

Accuracy and Repeatability:

• The high degree of accuracy and repeatability of modern CNC machines has been the single major benefit to many users. Whether the part program is stored on a disk or in the computer memory, or even on a tape (the original method). it always remains the same. Any program can be changed at will, but once proven, no changes are usually required any more. A given program can be reused as many times as needed, without losing a single bit of data it contains. True, program has to allow for such changeable factors as tool wear and operating temperatures, it has to be stored safely. but generally very little interference from the CNC programmer or operator will be required. The high accuracy of CNC machines and their repeatability allows high quality parts to be produced consistently time after time.

Contouring of complex shapes:

• CNC lathes and machining centers are capable of con- touring a variety of shapes. Many CNC users acquired their machines only to be able to handle complex parts. A good examples are CNC applications in the aircraft and automotive industries. The use of some form of computerized programming is virtually mandatory for any three dimensional tool path generation.

• Complex shapes, such as molds, can be manufactured without the additional expense of making a model for tracing. Mirrored parts can be achieved literally at the switch of a button. Storage of programs is a lot simpler than storage of patterns, templates, wooden models, and other pattern making tools.

Simplified tooling and Work holding:

• Nonstandard and 'homemade' tooling that clutters the benches and drawers around a conventional machine can be eliminated by using standard tooling, specially designed for numerical control applications. Multi-step tools such as pilot drills, step drills, combination tools, counter borers and others are replaced with several individual standard tools. These tools are often cheaper and easier to replace than special and nonstandard tools. Cost-cutting measures have forced many tool suppliers to keep a low or even a nonexistent inventory, increasing the delivery time to the customer. Standard, off-the-shelf tooling can usually be obtained faster then nonstandard tooling.

Cutting time and Productivity increase:

• The cutting time on the CNC machine is commonly known as the cycle time - and is always consistent. Unlike a conventional machining, where the operator's skill, experience and personal fatigue are subject to changes, the CNC machining is under the control of a computer. The small amount of manual work is restricted to the setup and loading and unloading the part. For large batch runs, the high cost of the unproductive time is spread among many parts, making it less significant. The main benefit of a consistent cutting time is for repetitive jobs, where the production scheduling and work allocation to individual machine tools can be done very accurately.

Read More about CNC machine:

Types of CNC machine: click here

Introduction to CNC machine: click here

advantages of CNC machine: click here

application of CNC machine: click here

Milling machines: click here