CNC-processing, bending, cutting and others
CNC acronym conceals computerized numerical control (Computer Numeric Control). Although these three letters together we see and hear often, except the people involved, for example in a CNC bending their meaning almost nobody knows. Although this technology fundamentally influenced the possibilities of industrial production.
We are mainly interested in the CNC sheet metal processing. Its main adjustment in this regard is the CNC sheet metal bending. At first we will have a look at the CNC fabrication and its meaning in general.
Should we try to describe CNC technologies in a human understandable form, we start with the principle of an automatic device, which gets its commands (information what to do, how to move and behave) in form of numbers. In the technical speech it works in the way that one device does the gross job (braking, bending) and the second device (servo) accordingly adjusts the movement in various axis (positioning), while this information is prepared in advance in the form of numbers(coordinates), thus numeric control.
In the praxis, nowadays, we often meet not only the control of positioning, but also the character of movement, in particular the speed. Thanks to this, the CNC fabrication has bigger control over the result. As the history shows, there was strong need for programmed fabrication machines already at the beginning of the 19th century. It was mainly about machining, thus the CNC sheet metal bending came later. The first attempts were very similar to for example an automatophon (barrel organ). The controlling mechanism (cams) manually leads the fabrication device, which was gross positioning and in addition it was influenced by the vibrations of the actual device.
Therefore new thoughts about a separate control mechanism from the fabrication mechanism and an abstract input of informations about motion arose quickly and the basis for the CNC sheet metal processing were laid. The first methods consisted of recording the information either in parallel patterning or repetition of motion. The CNC fabrication uses these analogous CNC machines in certain sectors to this day.
Press breaking and bending
An actual separation and thus a recorded sharp increase in accuracy was done by technologies that use two separate synchronized servos - called Seslyn (Synchros). There you can talk about management through abstract information that is similar to how today's CNC sheet metal processing works.
After the WWII, the USA finds a way to transfer information with the help of numbers and NC, so the numeric control was found. The origins we all about the punched cards. In the moment as the computer replaces the mechanical reading of the information from the punched card, the CNC fabrication was created.
The first programming language for CNC machines develops in the year 1956. It was still a long and complicated way to go, since we are talking about plain input of numbers. The real revolution for this technology was signified by the possibility of digitizing drawings without which the CNC sheet metal bending would not have such potential.
It was simply about taking over the 3D design as an instruction, which can be processed by CNC fabrication. After a series of experiments, the new Computer-Aided Design (CAD) was developed, which is still being improved and used for example in 3D printing till today.
The modern CNC sheet metal bending is not far from the original concept of CNC machining from the 50. Its about a table with a device which motion is controlled along multiple axes, normally at least two (X and Y),[2] and a tool spindle that moves in the Z (depth). The position of the tool is driven by motors through a series of step down gears in order to provide highly accurate movements, or in modern designs, direct-drive stepper motor or servo motors. The last major trend the CNC fabrication recorded, was the enclosure of the whole CNC machine into a big box.
The operation of these machines is nowadays completely separated from the fabrication. At the beginning might be raw sheet metal and at the end line sheet metal products thanks to the fact that more machines can be mechanically joined. Most of the modern CNC systems including the CNC sheet metal bending are fully electronically controlled.
CNC systems emerged from machining, but nowadays we use them for any process, which can be describes as a series of operations. Thus even the breaking and cutting, punching or bending of sheet metal. We can combine these within an enclosed process with laser cutting, point welding, welding, bending and cutting.
CNC sheet metal fabrication
Sheet metal products will no longer do without CNC. These are mainly metal bending and cutting. CNC fabrication in this regard has certain specifics. CNC sheet metal processing is used for end-products made of sheet metal as well as for the fabrication of sheet metal parts and assemblies. Many combination of technologies can be done at this process, for example with laser cutting, laser branding or CNC sheet metal bending on the press brake.
Key features of CNC
CNC fabrication has a key function for sheet metal processing in the industry, because metal parts are part of a large number of products from different areas. Sheet materials allow for easy changes as well as complicated product design capabilities thanks to the vast array of possible adjustments(from welding through bending to press breaking).
The only activity which has to be done separately nowadays is the powder painting. Even this, however, might be computer automated, similar to nut pressing or stud welding.
CNC fabrication brings the possibility small series and piece products of sheet metal, as well as their adjustments. In the past, the fabrication of sheet metal parts was done manually. It was not only expensive and time consuming, but it was especially very difficult to ensure consistent quality.
Sheet metal welding, punching and others
Nowadays tools for cutting and separating of sheet metal are CNC controlled and very universal. Often there are combined cells of laser separation and CNC bending. Furthermore these products may undergo the automatic welding (welding MIG/MAG,TIG/WIG as well as resistance welding).
Today is the limit CNC production mainly structural ingenuity blown into the CAD / CAM data. The engineer does not even have to leave the office so the new product sees the light of the world.
CNC sheet metal processing technology ensures high and consistent quality metal parts and the possibility of flexible changes in production. Its only drawback is still the high cost of establishing such a production.