Automated Welding With IO-Link

IO-Link technologies have been a game-changer for the welding industry. With the advent of automation, the demand for increasingly sophisticated and intelligent technologies has increased. IO-Link technologies have risen to meet this demand. Here I explain the concepts and benefits of I-O Link technologies and how they integrate into automated welding applications.

What are IO-Link technologies?

IO-Link technologies refer to an advanced communication protocol used in industrial automation. The technology allows data transfer, i.e., the status of sensors, actuators, and other devices through a one-point connection between the control system and individual devices. Also, it enables devices to communicate among themselves quickly and efficiently. IO-Link technologies provide real-time communication, enabling continuous monitoring of devices to ensure optimal performance.

Benefits of IO-Link technologies

    • Enhanced data communication: IO-Link technologies can transfer data between the control system and sensors or devices. This communication creates an open and transparent network of information, reflecting the real-time status of equipment and allowing for increased reliability and reduced downtime.
    • Cost-efficiency: IO-Link technologies do not require complicated wiring and can significantly reduce material costs compared to traditional hardwired solutions. Additionally, maintenance is easier and more efficient with communication between devices, and there is less need for multiple maintenance employees to manage equipment.
    • Flexibility: With IO-Link technologies, the control system can control and monitor devices even when not attached to specific operator workstations. It enables one control system to manage thousands of devices without needing to rewrite programming to accommodate different machine types.
    • Real-time monitoring: IO-Link technologies provide real-time monitoring of devices, allowing control systems to monitor failures before they occur, making it easier for maintenance teams to manage the shop floor.

How are IO-Link technologies used in automated welding applications?

Automated welding applications have increased efficiencies and continuity in processes, and IO-Link technologies have accelerated these processes further. Automated welding applications have different stages, and each step requires real-time monitoring to ensure the process is efficient and effective. IO-Link technologies have been integrated into various parts of the automated welding process, some of which include:

    1. Positioning and alignment: The welding process starts with positioning and aligning materials such as beams, plates, and pipes. IO-Link sensors can detect the height and gap position of the material before the welding process begins. The sensor sends positional data to the control system as a feedback loop, which then adjusts the positioning system using actuators to ensure optimal weld quality.
    2. Welding arc monitoring: The welding arc monitoring system is another critical application for IO-Link technologies. Monitoring the arc ensures optimal weld quality and runs with reduced interruptions. IO-Link temperature sensors attached to the welding tip help control and adjust the temperature required to melt and flow the metal, ensuring that the welding arc works optimally.
    3. Power supply calibration: IO-Link technologies are essential in calibrating the power output of welding supplies, ensuring consistent quality in the welding process. Detectors attached to the power supply record the energy usage, power output and voltage levels, allowing the control system to adjust as necessary.
    4. Real-time monitoring and alerting: Real-time monitoring and alerting capabilities provided by IO-Link technologies help to reduce downtime where machine health is at risk. The sensors monitor the welding process, determining if there are any deviations from the set parameters. They then communicate the process condition to the control system, dispatching alerts to maintenance teams if an issue arises.

Using IO-Link technologies in automated welding applications has revolutionized the welding industry, providing real-time communication, enhanced data transfer, flexibility, and real-time monitoring capabilities required for reliable processes. IO-Link technologies have been integrated at various stages of automated welding, including positioning and alignment, welding arc monitoring, power supply calibration, and real-time monitoring and alerting. There is no doubt that the future of automated welding is bright. With IO-Link technologies, the possibilities are endless, forging ahead to provide more intelligent, efficient, and reliable welding applications.

Future Proofing Weld Cell Operations

Weld cells are known for their harsh environments, with high temperatures, electromagnetic field disruptions, and weld spatter debris all contributing to the reduced lifespan of standard sensors. However, there are ways to address this issue and minimize downtime, headaches, and costs associated with sensor replacement.

Sensor selection

Choosing the appropriate sensor for the environment may be the answer to ensuring optimal uptime for a weld cell environment. If current practices are consistently failing, here are some things to consider:

    • Is there excessive weld spatter on the sensor?
    • Is the sensor physically damaged?
    • Is there a better mounting solution for the sensor?

For example, sensors or mounts with coatings can help protect against weld spatter accumulation while specialized sensors can withstand environmental conditions, such as high temperatures and electromagnet interferences. To protect from physical damage, a steel-faced sensor may be an ideal solution for increased durability. Identifying the root cause of the current problem is critical in this process, and informed decisions can be made to improve the process for the future.

Sensor protection

In addition to selecting the correct sensor, further steps can be taken to maximize the potential of the weld cell. The sections below cover some common solutions for increasing sensor lifetime, including sensor mounts and bunkers, and entirely removing the sensor from the environment.

Mounting and bunkering

Sensor mounting enables the positioning of the sensor, allowing for alignment correction and the possibility of moving the sensor to a safer position. Some examples of standard mounting options are shown in image 1. Bunkering is generally the better option for a welding environment, with material thickness and robust metal construction protecting the sensor from physical damage as displayed on the right in image 2. The standard mounts on the left are made of either plastic or aluminum. Selecting a mounting or bunkering solution with weld spatter-resistant coating can further protect the sensor and mounting hardware from weld spatter buildup and fully maximize the system’s lifetime.

Image 1
Image 2

Plunger probes

Using a plunger probe, which actuates along a spring, involves entirely removing the sensor from the environment. As a part comes into contact with the probe and pushes it into the spring, an embedded inductive sensor reads when the probe enters its field of vision, allowing for part validation while fully eliminating sensor hazards. This is a great solution in cases where temperatures are too hot for even a coated sensor or the coated sensor is failing due to long-term, high-temperature exposure. This mechanical solution also allows for physical contact but eliminates the physical damage that would occur to a normal sensor over time.

The solutions mentioned above are suggestions to keep in mind when accessing the current weld cell. It is important to identify any noticeable, repeatable failures and take measures to prevent them. Implementing these measures will minimize downtime and extend the lifetime of the sensor.

Leave a comment for a follow-up post if you’d like to learn about networking and connectivity in weld cells.

Magnetic Field Positioning Systems for Reliable, Accurate and Repeatable Absolute Position Feedback

Magnetic field positioning systems are increasingly popular due to their ability to provide reliable, accurate, and repeatable absolute position feedback.

These systems use magnetic field sensors to get a larger range of feedback across a pneumatic cylinder – a great alternative to traditional cylinder prox switches that may not work well in certain applications. They also allow for continuous monitoring of piston position in tight spaces, providing feedback in the form of analog voltage, current output, and IO-Link interface. And in many cases, these systems can replace the need for a linear transducer, making them a cost-effective solution for many industries.

One of the key benefits of magnetic field positioning systems is their versatility. They can be used in a wide range of industrial applications, such as:

    • Ultrasonic welding to validate set height with position feedback
    • Nut welding to verify set height with position feedback
    • Dispensing
    • Gripping for position feedback for different parts
    • Liner position indicators

While using these sensors greatly improves productivity in areas where prox sensors cannot provide the reliability needed, when selecting the magnetic field position system, it is important to consider the application requirements. The accuracy and feedback speed, for example, may vary depending on the application.

Magnetic field position systems are also available in different lengths. If the standard length does not meet requirements, you can choose a non-contact type that can be mounted on a slide with a magnetic trigger.

Overall, magnetic field positioning systems are an excellent choice for any industry that requires reliable, accurate, and repeatable absolution position feedback. With their versatility and flexibility, they are sure to improve productivity and efficiency in a wide range of applications.

Focusing on Machine Safety

Machine safety refers to the measures taken to ensure the safety of operators, workers, and other individuals who may come into contact with or work in the vicinity of machinery. Safety categories and performance levels are two important concepts to evaluate and design safety systems for machines. A risk assessment is a process to identify, evaluate, and prioritize potential hazards and risks associated with a particular activity, process, or system. The goal of a risk assessment is to identify potential hazards and risks and to take steps to prevent or mitigate those risks. The hierarchy of controls can determine the best way to mitigate or eliminate risk. We can use this hierarchy, including elimination, substitution, engineering, and administrative controls, and personal protective equipment (PPE), to properly mitigate risk. Our focus here is on engineering controls and how they relate to categories and performance levels.

Performance level

The performance level (PL) of machine safety components is a measure of the reliability and effectiveness of safety systems. Defined as EN ISO 13849-1 standard by the International Organization for Standardization (ISO), it is based on the probability of a safety system failing to perform its intended function. Performance levels are designated by the letters “a” through “e” with PLa being the lowest level of safety and PLe being the highest. Assessing the safety function of the machinery and evaluating the likelihood of a dangerous failure occurring determines the performance level.

Four levels of protection

The categories of machine safety components refer to the four levels of protection required to ensure the safe operation of machinery, as defined by the ISO. Figure 1 below shows how the measured risk determines the performance level and category of circuit performance.

    • Category 1: The occurrence of a fault can lead to loss of the safety function. Single channel safety circuit.
    • Category 2: The occurrence of a fault can lead to loss of the safety function between checks. Single channel safety circuit with monitoring.
    • Category 3: When a single fault occurs, the safety function is always performed. Some faults, but not all, can be detected, but the accumulation of those undetected faults can lead to the loss of the safety function. This category can be implemented using control reliable devices in a dual channel redundant safety circuit that includes monitoring.
    • Category 4: When a fault occurs, the safety function is always performed. Faults will be detected in time to prevent a loss of the safety function and is implemented using control reliable devices in a dual channel redundant safety circuit that includes monitoring.

Using control reliable devices is crucial in Category 3 and 4 safety circuits. One example of a control reliable device is a safety relay that mechanically interlocks the control contacts to the auxiliary contacts. Being mechanically interlocked means when the relay changes states the auxiliary contact will also changes states. Another example of a control reliable device is a safety PLC. A standard PLC is not rated to control safety functions because it is not control reliable and a malfunction could lead to the loss of a safety function.

 

The selection of the appropriate category and performance level for devices used to mitigate a risk in a machine is crucial for ensuring the safety of operators and other individuals. While it is important to note that the purpose of this blog is to provide information, it is not enough to qualify individuals to design or test safety systems. In summary, the category of machine safety defines the level of protection required for safe operation, while the performance level measures the reliability and effectiveness of safety systems.

Now let us go automate with a focus on safety!

Sensing Ferrous and Non-Ferrous Metals: Enhancing Material Differentiation

Detecting metallic (ferrous) objects is a common application in many industries, including manufacturing, automotive, and aerospace. Inductive sensors are a popular choice for detecting metallic objects because they are reliable, durable, and cost-effective. Detecting a metallic object, however, is not always as simple as it seems, especially if you need to differentiate between two metallic objects. In such cases, it is crucial to understand the properties of the metals you are trying to detect, including whether they are ferrous or non-ferrous.

Ferrous vs. non-ferrous

Ferrous metals, such as mild steel, carbon steel, stainless steel, cast iron, and wrought iron, contain iron. They are typically magnetic, heavier, and more likely to corrode than non-ferrous metals, which do not contain iron. Aluminum, copper, lead, zinc, nickel, titanium, and cobalt are examples of non-ferrous metals. They are typically nonmagnetic, lightweight, and less likely to corrode.

Sensing ferrous and non-ferrous metal:

When it comes to detecting ferrous and non-ferrous metals using inductive sensors, the reduction factor plays a crucial role. The reduction factor is the ratio of the sensor’s effective sensing distance for a given metal to the sensor’s effective sensing distance for steel. In other words, it is the degree to which a metal affects the sensing range of an inductive sensor. Ferrous metals typically have less of an effect on sensing range than non-ferrous metals because inductive sensors function based on the law of induction, and magnetic metals are more likely to interact with the magnetic field created by the sensor.

The reduction factor for each type of metal varies depending on the metal’s properties. Ferrous metals typically have a higher reduction factor than non-ferrous metals, which means they can be detected from a greater distance. For example, both steel and stainless steel have a reduction factor of 0.6 to 1, which means they can be detected from the full switching distance of the sensor of 4 mm. In contrast, non-ferrous metals, such as aluminum, copper, and brass, have a lower reduction factor of 0.25 to 0.5, which means they can only be detected from a fraction of the operating switching distance, typically 1 to 2 mm.

Understanding the reduction factor for each metal allows you to answer the question of what happens when you need to differentiate between two metallic parts. If one metal is ferrous and the other is non-ferrous, then you can place the sensor at a distance that will detect the ferrous metal but not the non-ferrous metal. However, this may not be an efficient solution if the metals have similar reduction factors, or if you need to detect the non-ferrous metal over the ferrous metal.

Using ferrous-only or non-ferrous-only sensors

The better solution is to use a ferrous-only or non-ferrous-only sensor. These sensors are specifically designed to detect only one type of metal and ignore the other type, resulting in a reduction factor of zero. Ferrous-only sensors detect only ferrous metals, and their reduction factors range from 0.1 to 1 for steel and stainless steel, while the reduction factors for non-ferrous metals such as aluminum, copper, and brass are zero. Non-ferrous-only sensors detect only non-ferrous metals, and their reduction factors range from 0.9 to 1.1 for aluminum, copper, and brass, while the reduction factors for ferrous metals are zero. Using ferrous-only or non-ferrous-only sensors eliminates the need to adjust the mounting distance of a standard inductive sensor to detect a ferrous metal over a non-ferrous metal.

Overall, selecting the right sensor for your application depends on the type of metals you need to differentiate and detect. If you are dealing with ferrous and non-ferrous metals, you can use a standard inductive sensor, but you need to be aware of the reduction factor for each metal type and adjust the mounting distance accordingly. If you need to detect only one type of metal, however, a ferrous-only or a non-ferrous-only sensor is the better option. These sensors are specially designed to ignore the other metal type, eliminating the need to adjust the mounting distance.

By understanding the differences between ferrous and non-ferrous metals and the capabilities of different sensors, you can optimize the metal detection system for maximum efficiency and accuracy.

Considerations When Picking UHF RFID

If you’ve attempted to implement an ultra-high frequency (UHF) RFID system into your facility, you might have run into some headaches in the process of getting things to work properly. If you are looking to implement UHF RFID, but haven’t had the chance to set things up yet, then this blog might be beneficial to keep in mind during the process.

UHF RFID and what it can do

UHF RFID is a long-range system with a focus on gaining visibility in the supply chain or manufacturing process. It can track multiple ID tags in a set area/distance (depending on the read/write head you select). The RFID field is emitted by an antenna that propagates an electromagnetic field, which will “ping and power up” a tag with data saved on it. Commonly, warehouses use it for logistics, supply chain tracking, warehouse pallet tracking, equipment tracking, or even for luggage tracking. As amazing as this technology sounds, there are environmental factors that can cause the system to not work to its full potential.

Factors affecting RFID system performance

Different materials or environments can affect the performance of your RFID system. Each tag antenna is set to a specific frequency, and some materials or environments can influence the radiation pattern. This can be something as simple as the material on which the tag is mounted to something more complex, such as how the signal is going to bounce off the walls or the ground. Below are some common issues people run into when implementing RFID.

    • Absorption: Absorption occurs when an object in the field absorbs part of the radio frequency energy emitted from the reader antenna. Cardboard, conductive liquids, and tissue (human bodies or animals) are examples of materials that can absorb some of the RF energy. One way to think of this is to imagine a sound booth in a recording studio. The booth is covered in foam to absorb sound. This is a similar philosophy for UHF RFID. You need to consider materials that absorb that energy.
    • Reflection: When there are distortions of the RF field, reflection can occur. As you may imagine, certain materials, such as metals, can cause the waves emitted from the antenna to distort or “reflect” in ways that cause performance losses. This could be metal machinery or fixings between the reader and the tags, a group of metal pipes, and mounting on metal containers. If you choose to do a deeper dive, there are other performance factors that can be impacted by the path of the signal, such as zones in which the tag can’t be reached (even if the tag is in the reader’s field), or the tag and the reader are not aligned properly.
    • Detuning: Detuning occurs when the radio frequency between the tag and reader is changed in the process. Since you pair specific readers to specific tags at a specific frequency, you don’t want your environment to cause a change in the specific frequencies. Certain materials, such as cardboard, metals, tissue, and plastics, can cause an impedance that can “un-match” your reader and tags based on the RF not matching up.

Luckily for you, many companies who specialize in RFID can help ensure you pick the right system for your application. Some will even go visit your site to evaluate the environment and materials that will be involved in the process and recommend the right readers, antennas, tags, and accessories for you.

Although not all UHF RFID applications seem complex, there are many small things that can affect the entire operation. When you are picking your system, make sure you keep in mind some of these effects, and if you are unsure, call in a professional for some assistance.

Tackling the Most Demanding Applications With Precision Sensors

Standard industrial sensors can solve a lot of automation challenges. Photoelectric, capacitive, and inductive technologies detect presence, distances, shapes, colors, thicknesses, and more. To satisfy these general applications, there are a few reputable manufacturers in the market that design and produce such products. In many instances, it is possible to interchange them from manufacturer to manufacturer, due to similar mounting patterns, technical specifications, connectors, and even common pin assignments.

But some applications require more precision – where standard sensors will not do.  Some examples include:

    • The target may be too small or difficult material to detect
    • The target may move very slowly, or very quickly
    • The target may have a minimal displacement, as in valve feedback
    • The sensor must have low mass, for high-acceleration applications
    • The sensor location has severe space constraints or material constraints

Applications that must detect particles that can’t be seen with the naked eye, or something as small as sensing the thin edge of a silicon wafer or the edge of a clear glass microscope slide, require sensors with exceptional precision.

Many precision sensing applications require a custom-designed sensor to meet the customer’s expectations. These expectations typically involve a quality sensor with robust attributes, likely coupled with difficult design parameters, such as high switch-point repeatability, exceptional temperature stability, or exotic materials.

What constitutes a precision sensing application? Let’s take a look.

Approximately 70% of all medical decisions are based on lab results. Our doctors are making decisions about our health based on these test outcomes. Therefore, accurate, trustworthy results, performed quickly, are priorities. Many tests rely on pipetting, the aspirating and dispensing of fluids – sometimes at a microscale level – from one place to another. Using a manual pipette is a time-consuming, labor-intensive process. Automating this procedure reduces contamination and eliminates human errors.

To satisfy the requirements of an application such as this requires a custom-manufactured LED light source, with a wavelength chosen to best interact with the fluids, and an extremely small, concentrated light emission that approaches laser-like properties (yet without the expense and power requirements of the laser). This light source verifies pipette presence and dispensing levels, with a quality check of the fluids dispensed down to the nanoliter scale.

So, the next time you face an application challenge that cannot be tackled with a standard sensor, consider a higher precision sensor and rest assured you will get the reliability you demand.

Using Guided Changeover to Reduce Maintenance Costs, Downtime

A guided changeover system can drastically reduce the errors involved with machine operation, especially when added to machines using fully automated changeovers. Processing multiple parts and recipes during a production routine requires a range of machines, and tolerances are important to quantify. Only relying on the human element is detrimental to profits, machine maintenance, and production volumes. Implementing operator assistance to guide visual guidance will reveal inefficiencies and allow for vast improvements.

Removing human error

Unverified manual adjustments may cause machine fatigue or failure. In a traditional manual changeover system, the frequency of machine maintenance is greater if proper tolerances are not observed at each changeover. Using IO-Link can remove the variable of human error with step-by-step instructions paired with precise sensors in closed-loop feedback. The machine can start up and run only when all parts are in the correct position.

Preventative maintenance and condition monitoring

Preventative maintenance is achievable with the assistance of sensors, technology, and systems. Using condition monitoring for motors, pumps and critical components can help prevent the need for maintenance and notably improve the effectiveness of maintenance with custom alerts and notifications with a highly useful database and graphing function.

A repeatable maintenance routine based on condition monitoring data and using a system to guide machine changeover will prolong machine life and potentially eliminate downtime altogether.

For more, read this real-world application story, including an automated format change to eliminate human error, reduce waste and decrease downtime.

Securing Your Supply Chain and Beefing Up Traceability

 

Snake oil is one of the most maligned products in all of history. Synonymous with cure-alls and quackery, it is a useless rip-off, right? Well, no, it’s actually high in the Omega 3’s, EPA, and DHA.

Snake oil fell from prominence because it was all too easy for charlatans to brew up fake oil and pass it off as the genuine article, with sometimes dangerous outcomes.

Today’s customers are smarter than ever and waking up with ever-evolving knockoffs. We are more aware of fake reviews and fake products. Brands that can prove their products are genuine can command higher prices and forge long-standing customer relationships. This starts with securing your supply chain and beefing up traceability.

Securing your brand

Many roads lead to Rome and no single technology will be the one silver bullet to secure your supply chain. That said, RFID technology is likely to play an important role. RFID allows for multi-read without a line of sight, making it a great choice in both production and warehouse/logistics environments. Perhaps more importantly, RFID tags can be encrypted. This adds protection against would-be cheats. The ability to both read and write provides additional flexibility for tracking and tracing in production.

RFID is not the only traceability solution and smart companies will use a combination of technologies to secure their brands. We’ve seen holograms on baseball cards and QR codes on underwear. We’ve seen authorized retailer programs … and RFID on coffee cups and medical devices. As you think through the various options, it’s worth keeping in mind the following 4 questions:

      1. Is the technology secure? Does it support modern cryptographic methods?
      2. Does the solution add value – i.e. improve current processes?
      3. Is the technology future-proof?
      4. Is the technology robust?

Any technology that answers yes to these questions will be well-suited to meet this new market. Brands that stay ahead of the curve will grow and those who fall behind the curve risk ending up in the dustbin – right next to the snake oil.

Navigating the Automotive Plant for Automation Opportunities

When one first looks at an automotive manufacturing plant, the thought of identifying opportunities for automation may be overwhelming to some.

These plants are multi-functional and complex. A typical plant manages several processes, such as:

    • Press, stamping, and dye automation
    • Welding, joining, and body in white
    • Painting
    • Final assembly
    • Robot cell
    • Material handling, including AGV, conveyor, and ASRS
    • Engine and powertrain assembly
    • Casting and machining parts
    • EV and EV sub-processes

Navigating the complexity of the automation processes in your plant to promote more automation products will take some time. You will have to look at this task by:

Time. When tackling a large automotive plant, it’s important to understand how to dissect it into smaller parts and spread out your strategies over a full year or two.

Understanding. Probably the most important thing is to understand the processes and flow of the build assembly process in a plant and then to list the strategic products that can be of use in each area.

Prioritizing. Once you have a good understanding of the plant processes and a strategic timeline to present these technologies, the next step is to prioritize your time and the technology to the highest return on investment. You may now learn that your company could use a great deal of weld cables and weld sensors, for example, so this would be your starting point for presenting this new automation technology.

Knowing who to talk to in the plant. The key to getting the best return on your time and fast approval of your automation technology is knowing the key people in the plant who can influence the use of new automation technology. Typically, you should know/list and communicate monthly with engineering groups, process improvement groups, maintenance groups, purchasing and quality departments. Narrowing down your focus to specific groups or individuals can help you get technology approval faster, etc. Don’t feel like you need to know everyone in the plant, just the key individuals.

Knowing what subjects to discuss. Don’t just think MRO! Talk about the five technology opportunities to have new automation in your plant, including:

        1. MRO
        2. Large programs and specs
        3. Project upgrades
        4. Training
        5. VMI/vending

Most people concentrate on the MRO business and don’t engage in discussions to find out these other ways to introduce automation technology in your plant. Concentrating on all five of these opportunities will lead to placing a lot of automation in the plant for a very long time.

So, when you look at your plant be very excited about all the opportunities to present automation throughout it and watch your technology levels soar to levels of manufacturing excellence.

Good luck as you begin implementing your expansion of automation technology.