In machining operations, tool breakage is an ever-present challenge. However, thanks to technological advancements, the issues breakage used to cause can become a thing of the past. Even the best tools eventually wear down and need replacement, but with the right equipment, shops can detect and deal with breakages immediately and minimize disruption to operations. Let’s discuss how.
What’s behind the rise in popularity of tool breakage detection systems
In the past, even as real-time data became accessible to more operators, tool breakage detection wasn’t exactly easy. Detection systems existed, but their sensitivity was weak. Their cost was also a factor; stoppages and rework could be expensive, but so could purchasing and integrating new detection systems. Shops had to weigh the costs against each other.
Fortunately, the latest technology makes tool breakage detection far more attainable and affordable for the average shop. Sensors are more advanced. Machines can communicate with one another in real-time. With the right sensors and controls, you don’t even have to stop operations to inspect tools. As a result, more and more shops are adopting breakage detection systems.
6 Benefits of using a tool breakage detection system
Tool breakage detection systems present a whole host of benefits, especially as they’ve become more intuitive and accessible for the average shop owner. Here are some of the most significant:
The sooner a breakage is detected (or predicted, as we’ll see below), the more prepared operators will be to handle it. Disruption to operations can be minimized, maintaining production schedules—and minimizing the time operators spend waiting for the machine to turn back on.
Breakage is inevitable. In the past, that meant so were unplanned work stoppages, unnecessary rework and scrapped parts, all of which hampered productivity. With detection systems, what was once the cost of doing business—lost time—can now be prevented. As a result, productivity isn’t just preserved; it’s increased. Shops with detection systems find and replace broken tools faster, leading to an overall boost in productivity.
In addition to ruining workpieces, tool breakage raises the likelihood of worker injury. Damaged tools can cause accidents, require manual handling of equipment, or even (in extreme cases) send debris flying across the shop floor. Detecting the breakage early minimizes those risks.
Every moment a machine is down costs you money that could have been spent on production. Plus, broken tools don’t just damage parts—they can damage other equipment, too. Conversely, early detection of breakage prevents costly damage, wasted hours, or wasted material. Less money wasted means more money made, raising cost-effectiveness.
A broken tool’s effects aren’t always apparent right away. Those slight changes in tool behavior may not damage a part enough to be scrapped outright, but if a shop doesn’t notice or re-check for subtle effects, it may end up shipping lower-quality parts. Detecting breakage when it occurs prevents defects and minimizes rework, resulting in higher quality and more consistency for your customers overall.
Shop owners, wary of risking any of breakage’s unfortunate effects, may engage in preventive maintenance—switching out tools at an arbitrary point of operation regardless of whether they’ve truly reached the end of their lives. While this does prevent breakage, it’s an inefficient use of resources.
Thanks to the power of data analytics, predictive maintenance is possible. Predictive maintenance uses available operating data to determine when a tool really needs to be replaced. Rather than preemptively replacing a tool, or doing so after it breaks, shops can replace that tool right before it reaches the end of its operating life. If operators know exactly when breakage will occur, they can plan for downtime, minimize disruption and still get the most out of every tool.
Most popular types of broken tool detection systems and how they work
Every shop has unique needs that affect their choice of detection system. The mechanism of action is similar for all of them: First, operators establish a baseline by measuring factors like vibration and force before the tool machines any parts. Tool performance is then monitored through the system, which looks for deviations from specifications or unusual tool behavior.
Depending on the level of integration and automation, machines may stop themselves, or flag the issue for operators on their CNC control. However, that’s where most similarities end. Here are a few of the most popular systems:
With a contact sensor tool breakage detection system, direct contact between the sensor and tool provides information on the tool’s condition. Measurements taken through direct contact are fast and accurate, but there are disadvantages.
Contact sensors aren’t ideal for hard-to-access parts of the machining setup. Plus, while physical contact provides detailed measurements, it can interfere with the machining process during delicate or high-speed operations. At times metal chips or other debris may affect measurements, which can interfere with the system. Clearing those out may require additional maintenance, which raises total cost of ownership (TCO). And there’s the simple matter of wear and tear. Since the parts are actually touching one another, the sensor’s operating life may shorten.
Laser-based systems never touch the tool. Instead, they are placed near the tool and shine directly at it during machining. Every tool affects light in different ways—and those effects are detected as the laser scatters and reflects back to a measurement device. Data such as changes to the beam’s intensity and wavelength is captured and compared to the system’s baseline.
These systems are highly sensitive and ideal for situations where physical contact could interfere with machining, but they’re not without drawbacks. Laser-based detection systems are often expensive, difficult to install and time-consuming to calibrate. That’s not ideal for smaller shops, or for any shop trying to retrofit existing equipment.
Lasers can only measure in two dimensions (some systems get around this by pairing with contact technology). In addition, the system’s dependence on reflected light causes unique issues. Complex geometries and small cutting edges, as well as certain materials, can seriously affect accuracy. So can environmental conditions like dust or coolant—passing through those may cause additional scattering of light. Physical debris may also block the laser or its lens. In both cases, frequent cleaning is necessary, again potentially raising TCO.
Other non-contact sensors
There are many other kinds of non-contact sensors, each with their own advantages and disadvantages. For example, infrared sensors can monitor temperature spikes in tools and materials. Machine vision systems use cameras and image processing software to analyze tool performance. However, one of the most promising non-contact systems uses inductive sensors.
Unlike laser-based systems, which detect and interpret changes in light, inductive sensors use electromagnetism. An inductive sensor generates an electromagnetic field. Metal changes this field’s properties as it passes through; during operation, any effects to the field are detected almost immediately, despite the lack of physical contact between the sensor and the tool. This results in faster data acquisition, simpler hardware and higher accuracy—even with extremely small tools.
The HEIDENHAIN TD 110 is the prime example of the inductive sensor’s advantages. It’s sensitive enough to easily inspect microtools with accuracy down to 2mm, yet the hardware is simple—requiring only one cable—and operation is intuitive. TCO is lower, too—without emitters or lenses and its single cable, it doesn’t need maintenance. Coolant and contamination don’t affect the electromagnetic field, so no additional cleaning is required.
That simplicity speeds up the tool change process, making it up to six seconds faster than a laser-based system. If a shop uses a TNC7 control, operators can shorten idle time even more thanks to the control’s process monitoring functionality—and if they encounter any issues, HEIDENHAIN offers remote support.
Notably, any control can be retrofitted with the TD 110. The system’s nondisruptive size makes it easy to install regardless of the equipment.
Considerations for selecting the right detection system for your operation
With all this in mind, we’re left with the question: “Which detection system is right for me?” These are some factors to consider:
- Sensitivity settings
- Environmental conditions
- International standard requirements
Tool breakage detection systems have advanced by leaps and bounds since the days of pure visual inspection. With the right system, shops can achieve greater efficiency, more profitability—and less stress for the operators using the tools every day. If you consider your purchases carefully, weigh needs against costs and match your choice of system to your operation, you’ll set yourself up for ever-greater success.
If you’re interested in what the TD 110 can do for your shop, visit the product page, or contact HEIDENHAIN to learn more.