In today's manufacturing industry, automation is becoming more and more commonplace across industries. One application where we've seen particular growth recently is CNC machine tending.
For many manufacturers, automation is a key for remaining competitive. By automating your processes, you can boost productivity, improve quality, and shorten lead times while decreasing costs.
Many of your competitors are probably already using robots in their businesses. By using robots to control your CNC machines, you get the advantage of the same benefits as them rather than falling behind.
Let's have an overall look at CNC machine tending, its various benefits, and how you can start to automate machining applications in your business.
What is machine tending?
Simply put, machine tending is the process of using a robot to automate the tasks associated with CNC machining.
These tasks commonly include loading and unloading the workpiece, and activating various parts of the CNC cycle.
Machine tending can be a highly efficient way to manage a factory floor. It can help reduce the need for human workers to perform dull, repetitive tasks, helping you make better use of your human resources. It can also help reduce the risk of injuries associated with repetitive motions.
We find that machine tending is often one of the first tasks that machine shops are keen to automate. If you've been considering automating, you probably recognize that loading and unloading machines is just not the best use of your workers’ time.
7 compelling benefits of automating a CNC process
There are many benefits to automating a CNC machine with a robot.
Perhaps the most obvious benefit that most people think of first is increased productivity. A robot CNC machine can operate 24 hours a day, 7 days a week, without breaks or downtime.
However, there are other benefits that might be less obvious but can have an even larger effect on your production.
Here are 7 compelling benefits to automating your CNC machine with a robot:
1. Decreased downtime
By tending your machine with a robot, that machine spends less time doing nothing. This helps to improve the Overall Equipment Effectiveness of that CNC machine.
2. Increased flexibility
You can quickly and easily reprogram a robot to handle new product variants and changes. This improves the flexibility of your CNC machine compared to other forms of automation.
3. Enhanced accuracy
With manual machine tending, there is always a possibility that an operator will place a workpiece in the machine in slightly the wrong position or orientation, ruining that piece. A robot always places it in exactly the right position every time.
4. Improved safety
Using a robot to automate your CNC machining process can help to create a safer working environment by eliminating the need for human workers to be close to moving machinery.
5. Reduced costs
Robotic automation can help reduce the overall cost of manufacturing. It allows you to make the best use of your labor costs by removing non-value-added tasks from the hands of human workers.
6. Increased consistency
While productivity is often the headline benefit of robotics, consistency is usually a more useful benefit. The improved consistency of your robotic CNC machine can have a significant impact over time, affecting many aspects of your production process.
7. Better quality control
Automating your CNC process with a robot also makes quality control simpler and quicker. By reducing human error, you gain better overall control of your product quality.
Examples of 3 CNC machines you can improve with automation
Robots are very flexible so you can automate almost any CNC machine if you approach it in the right way. Some will be easier to deploy than others.
Here are 3 common types of CNC machines you can improve with robotic automation:
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CNC Lathe — Lathes are used to create symmetrical objects such as shafts, cylinders, and poles. Robots can easily handle the action of placing a workpiece precisely in the lathe jaws.
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CNC Milling Machine — A milling machine can create complex shapes using a rotary cutter. Adding a robot makes your milling process more efficient and can give you more options for even more complex shapes.
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Laser Cutter — Laser cutting is an increasingly popular process for creating complex shapes in a variety of materials. Using a robot to place robots in a laser cutter can be one of the simplest types of machine tending as it is often just a pick and place motion.
These are probably the most common CNC machines you would want to automate. However, you can apply machine tending robots to almost any automated or semi-automated machine you like.
How to deploy machine tending robots
If you are looking to apply machine tending robots to your process, there are some steps you can take to make your life easier.
The first — and possibly most important — step is just to pick the right robotic solution up front.
Using an integrated application kit for robotics is a good way to get up and running quickly, reducing a lot of the friction that people often experience with robotic deployments.
You can find out about machine tending application kits in this blog article.
What the future holds for CNC machining
Over the years, robotic technology has become easier to use and more accessible for people with no previous experience with robots.
As you can see, automating your CNC with a robot can have many benefits. With each step to make robots easier to use, more manufacturers will use the technology.
It seems likely that we will see robotic machine tending become a required addition to many CNC machines. When you buy a CNC machine, you also get a robot to tend that machine.
Rather than asking "Why should I automate with a robot?" the question will become "Why wouldn't you!?"
Which type of CNC machine would you like to automate first? Tell us in the comments below or join the discussion on LinkedIn, Twitter, Facebook, or the DoF professional robotics community.
Robotic Machine Tending - Advantages and Disadvantages
Robotic machine tending can increase productivity and improve the working environment. However, demanding safety regulations and expensive vision systems might make investments in the popular application more challenging. This article highlights the advantages and disadvantages of robotic machine tending.
Advantages
Machine tending refers to a robot overseeing a machine, for example a CNC machine. A typical machine tending application consists of a robot loading and unloading the parts while the machine operates on them.
Machine tending reduces the risk of injury
Machine tending assists in making the production floor a safer space. By using a robot instead of a human to feed a machine with material or parts, the probability of injury is significantly decreased. In case an employee approaches the cell, the robot can be programmed to slow down, further eliminating the risk of injury. In addition, it frees employees from the tedious job of loading and unloading and gives them time to focus on more productive tasks. This creates more value for the company and encourages employees to further develop their competences.
Machine tending can raise productivity
Use of robots for machine tending raises speed and decreases part cycle time (the time needed for one piece to be finished) as a result. Usually, it is only a matter of difference in seconds compared to a human operator, but over weeks and months this can prove as a major boost in productivity as a whole. Especially because a robot can work for weeks in a row without stopping. The robot can also run a couple of hours after normal workday unattended, thus providing more capacity without the need for further operators.
The robot can
have
more uses than just loading/unloading
By default, the robot just moves the material from point A (e.g. bin) to point B (e.g. CNC machine) during a machine tending application. However, some of the robots used for machine tending applications are often cobots (collaborative robots), meaning that they have a flexibility which can be used for other tasks in the factory such as finishing applications. Depending on the fragility of the product, tasks like polishing, sanding, deburring etc. are often better done by a robot than a human employee, as robots are typically more faster and more consistent.
(See also: The Pros and Cons of Collaborative Robots – Flexibility vs. Efficiency)
Robots can tend more than one machine
Given the right mounting such as rail, floor or ceiling mounting, a robot can tend multiple machines at the same time (also known as parallel machine tending). The robot can be strategically placed between two machines or above them and load and unload parts to both of them. If the machine is big enough, the robot can even be placed inside the machine. In any case, all those options could save space on the factory floor and reduce movements between processes.
Parallel machine tending: One robot operating several machines.
Disadvantages
Machine tending
sometimes
calls for vision systems which can
be
very expensive
The use of a robot comes with a high cost, including the robot itself, maintenance costs, different tools corresponding to different pieces fed to the machine, and sometimes the need for a vision system. Such a system is crucial to verify if the material is successfully processed by the machine.
If the robot picks up parts that are in a fixed position, a vision system is optional but recommended, as it can detect and discard bad parts before they are further processed. However, if the robot needs to pick up parts that are scrambled around, a vision system is essential. Vision systems can cost up to 50.000 dollars and therefore raise the cost of the investment significantly.
Robots may find it hard to handle different kinds of material
Depending on whether the robot tends more than one machine or different parts, materials and shapes are used, the robot might fail in grasping all those parts efficiently. Therefore, different grippers need to be placed on the robot each time. A solution to that problem is to have all of them already mounted and just rotate the end-effector of the robot to get the correct tool in front, ready to grasp.
By rotating the end-effector, one robot with more grippers can pick up different parts.
Machine tending and CE marking
According to European Union requirements, every machine needs to be CE marked before being marketed in the EU. This includes a risk assessment as well as preparing an instruction manual and other documents stating that all safety requirements are met. Similar rules apply for machines outside of the EU as well. Now if two new machines are combined or assembled (e.g a robot and a CNC machine), apart from the individual risk assessment of each machine, a new assessment must be carried out based on the application. This complicates things of course. In case of parallel machine tending, things get even more challenging.
Conclusion
Machine tending is an automation solution that can be worth applying to your production floor. It can improve productivity and relieve employees from tedious task. However, potential challenges like complications with CE marking or an expensive vision system could turn this into a more challenging investment.