CNC Welding : A Comprehensive Guide [2021]

Tired of all the mechanical work? CNC Welding was invented just to fill the gap created by all the mechanical work involved in welding.

So what exactly is CNC Welding?

A CNC(Computed Numerically Controlled) system is an automated system that carries out very complex interrelated tool actions in a pre-programmed sequence, for the fabrication of items to extremely exacting standards. 

A whole series of different automatic tools can be combined into a single CNC “cell,” which takes an item through a sequence of different processes to cut, shape, weld, assemble, and finish the piece without the need for human intervention (unless the program needs to be changed or something goes wrong). 

The Computed Numerically Controlled (CNC) system is one of the automatic control systems that are used in many different environments.

CNC Welding Machine
CNC Welding Machine

How CNC Welding Came into Existence? 

Among the many tools that have been used to create the technological infrastructure of the twentieth and early twenty-first centuries, the welding machine and the computer are two of the most central. 

Welding machines are used in the manufacture of practically every other kind of machine and device, as well as many types of packages and containers, and so are at the core of nearly all modern production. 

Computers have revolutionized the world in several ways as well. They have made massive amounts of information commonly available in a few moments to nearly anyone on Earth. 

They have allowed enterprising entrepreneurs and freelancers to achieve success with little more ‘starting capital’ than their initiative and intelligence. 

And they have made precisely-designed, complex automatic control systems possible. Hence, the fusion of computers and welding machine gave birth to the idea of CNC Welding Machines.

Welding machines can be incorporated into a CNC cell or simply controlled by a CNC system to allow complex welding tasks to be automatically carried out, with a stunning degree of accuracy. 

These specially designed CNC welding machines are usually employed in an industrial setting, as would be expected from a machine of this complexity, and with such demanding programming needs.

Also CNC welding eliminated the use of weld logs and maps, and made the process completely automated without any human interference.

CNC Welding Machine

CNC welding machines can be of various kinds – MIG, TIG, Plasma arc, multi-process, and so on, depending on the specific model. 

Many have large beds to accommodate the workpiece so that it will remain in place without human assistance while the welding operations are carried out. 

Rotary tables are fitted to some models to increase the welding possibilities. 

The exact type of welding machine that is chosen depends on which substances are likely to be welded at the factory, and what the metal is being used for in the final product.

A CNC welder is programmed with a “Welding Path” – a pattern of welding that it will follow with each piece that it works on. 

This welding path can be very complicated – this still does not make the CNC welder quite as flexible as a living, manual welder, since it cannot cope with anything unexpected. 

However, it does allow the CNC welding machine to assemble very intricate items with a high degree of precision.

Many specific parameters of the welding job can also be programmed in so that if different parts of the same workpiece have different welding needs, these will be met by the CNC machine. 

The arc height and amperage can be varied for preprogrammed parts of the welding path.

For example, If the welder has a wire feed for filler metal, this can be set to turn on and off, creating gaps in the weld where needed. 

All of this allows for smooth, intricate, and extremely exacting welding to be carried out. 

Better yet, each CNC machine can store several thousand different programs, allowing it to be switched between functions as needed.

CNC welding machines are not quite as flexible as a human welder, but they can outdo humans in many welding jobs, creating complex welds rapidly and with inhuman exactitude. 

Sometimes, the machine is equipped with cameras for inspection. The visuals are strictly monitored to look out for any mistakes that might happen.

They are good both for large-scale production and for extremely specialized jobs like making parts for race-car engines, where the slightest variation in the weld could cause a catastrophic failure when the part is at maximum stress, being used in the world outside the factory. 

The CNC welding machine can also be made part of a CNC cell that will handle the creation of an object from its basic materials to its finishing, depending on the complexity of the CNC system that has been arranged.

CNC Laser Metal Cutting
CNC Laser Welding Machine

Requirements for CNC Welding

To get started, CNC requires you to have basic knowledge of computers and programming.

CNC Welding Program is done via the G-Code programming language. They feed the instructions to the CNC machine based on the code.

If you are not familiar with programming, you must know how to work with CAD(Computer-aided design). 

CAD is essentially a software which converts a 2D or 3D design into computer understandable code.

AutoCAD is one such popular software which helps you with CNC welding by providing an environment to use CAD.

The design or the code is tested before executing it to ensure there is no risk or mistakes.

The CNC Machining System is majorly divided into two parts:

Open Loop Machining System

In an open loop machining system, the system receives instructions and only runs in a single direction between the controller and the motor.

These systems are not that accurate and may produce undesirable results sometimes.

Closed Loop Machining System

The closed loop system is much more superior when compared to the open loop systems. 

Since, these systems are capable of receiving feedback, which is then measured via analog or digital systems.

These systems are very powerful and accurate due to the automatic error correction capability which also corrects any variation in real-time.

Uses of CNC Welding 

CNC welding machines are automated and worked on the program fed to it, thereby reducing the risks of any workplace incidents

Since the requirement of mechanical work is minimal for CNC welding, they are majorly used in:

  1. Automobile Industry: The CNC Welding Machines incorporate strong laser welding, which is a great advantage for automotive industries as they require cutting and joining of metal parts precisely.
  2. Electronics Industry: Similar to the automobile industry, electronics needs precision work done onto them. Since CNC is cost-effective and very efficient in the tasks, they are preferred over other modes of fabrication.
  3. Plastic Industry: Generally having a low melting point, regular welding methods are usually avoided when working with plastics. Hence, CNC laser welding is used for them, which results in clean joints.

Other Functions of A CNC Machine

Apart from welding, CNC Machines can be used for a whole lot of other purposes such as

  • Laser Cutting
  • Lathe Machines
  • Water Jet Cutting
  • Glass Cutting
  • 3D Printing
  • Micro Welding

Conclusion

With this article, I tried to explain how CNC welding works, The ultimate innovation that happened to the field of welding. 

Similar to robotic welding, It simplified industrial works which were hard to tackle and increased efficiency by many folds.