Today’s consumer packaged goods (CPG) market is driving the need for greater agility and flexibility in packaging machinery. Shorter, more customized runs create more frequent machine changeover. Consequently, reducing planned and unplanned downtime at changeover is one of the key challenges CPG companies are working to improve.
Many packaging machine builders are now providing fully automated changeover, where motors move pieces into the correct position upon recipe change. This has proven to be a winning solution, however, not every application can accommodate motors, especially those on older machines.
Guided changeover represents an opportunity to modify or retrofit existing equipment to improve agility and flexibility on older machines that are not yet ready to be replaced.
An affordable intermediate step between fully manual and fully automated changeover:
A measurement sensor can be added to provide position feedback on parts that require repositioning for changeover. By using indicator lights, counters or displays at the point of use, the operator is provided with visual guidance to reposition the moving part. Only once all parts are in the correct position can the machine start up and run.
By utilizing this concept, CPG companies can realize several key benefits:
Reduced planned downtime: Adding guidance reduces the amount of time it takes to move parts into the correct position.
Reduced unplanned downtime: Providing operator guidance minimizes mistakes, avoiding jams and other problems caused by misalignment.
Reduced waste: Operators can “dial in” moving parts quickly and precisely. This allows the machine to be fully operational sooner, minimizing runoff and scrap.
Improved operator training: Providing operator guidance helps CPG companies deal with inevitable workforce attrition. New operators can be quickly trained on changeover procedures.
Selecting the correct sensor
A variety of sensor technologies can be used to create guide changeover; it’s really a matter of fit, form and function. Common technologies used in changeover position applications include linear positioning transducers and encoders. Other devices like inductive and photoelectric distance sensors can be used with some creativity to solve challenging applications.
Available mounting space and environmental conditions should be taken into consideration when selecting the correct device. Sensors with enhanced IP ratings are available for harsh environmental conditions and washdown.
Analog devices are commonly used to retrofit machines with older PLCs, while IO-Link can be used in place of analog for a fully digital solution, enabling bi-directional communication between the sensor and controller for condition monitoring, automatic device replacement and parameter changes.
Packaging industries must operate with the highest standards of quality and productivity. Overall Equipment Effectiveness (OEE) is a scoring system widely used to track production processes in packaging. An OEE score is calculated using data specifying quality (percent of good parts), performance (performance of nominal speed) and equipment availability (percent of planned uptime).
Quality issues can directly impact the customer, so it is essential to have processes in place to ensure the product is safe to use and appropriately labeled before it ships out. Additionally, defects to the packaging like dents, scratches and inadequate labeling can affect customer confidence in a product and their willingness to buy it at the store. Issues with quality can lead to unplanned downtime, waste and loss of productivity, affecting all three metrics of the OEE score.
Traditionally, visual inspections and packaging line audits have been used to monitor quality, however, this labor can be challenging in high volume applications. Sensing solutions can be used to partly automate the process, but complex demands, including multiple package formats and product formulas in the same line, require the flexibility that machine vision offers. Machine vision is also a vital component in adding traceability down to the unit in case a quality defect or product recall does occur.
Vision systems can increase productivity in a packaging line by reducing the amount of planned and unplanned downtime for manual quality inspection. Vision can be reliably used to detect quality defects as soon as they happen. With this information, a company can make educated improvements to the equipment to improve repeatability and OEE and ensure that no defective product reaches the customers’ hands.
Some vision applications for quality assurance in packaging include:
Check that a label is in place, lined up correctly and free of scratches and tears. Ensure that any printed graphics, codes and text are legible and printed with the expected quality. Use a combination of OCR (Optical Character Recognition) to read a lot number, expiration date or product information, and then OCV (Optical Character Verification) to ensure legibility.
Primary and secondary packaging inspection for dents and damage
Inspect bottles, cans and boxes to make sure that their geometry has not been altered during the manufacturing process. For example, check that a bottle rim is circular and has not been crushed so that the bottle cap can be put on after filling with product.
Safety seal/cap presence and position verification
Verifying that a cap and/or seal has been placed correctly on a bottle, and/or that the container being used is the correct one for the formula / product being manufactured.
Product position verification in packages with multiple items
In packages of solids, making sure they have been filled adequately and in the correct sequence. In pharmaceutical industries, this can be used to check that blister packs have a pill in each space, and in food industries to ensure that the correct food item is placed in each space of the package.
Certification of proper liquid level in containers
For applications in which it can’t be done reliably with traditional sensing technologies, vision systems can be used to ensure that a bottle has been filled to its nominal volume.
The flexibility of vision systems allows for addressing these complex applications and many more with a well-designed vision solution.
For more information on Balluff vision solutions and applications, visit www.balluff.com.
In all industries, there is a need for more flexible and individualized production as well as increased transparency and documentable processes. Overall equipment efficiency, zero downtime and the demand for shorter production runs have created the need for smart machines and ultimately the smart factory. Now more than ever, this is important in the Packaging, Food and Beverage (PFB) industry to ensure that the products and processes are clean, safe and efficient.
Take a look at how the Smart Factory can be implemented in Packaging, Food, and Beverage industries.
Updating Controls Architecture
Eliminates analog wiring and reduces costs by 15% to 20%
Enables visibility down to the sensor/device
Eliminates manual configuration of devices and sensors
Automating Guided Format Change and Change Parts
Eliminates changeover errors
Reduces planned downtime to perform change over
Reduces product waste from start-up after a change over
Consistent positioning every time
Ensures proper change parts are swapped out
Predictive Maintenance through IO-Link
Reduces unplanned downtime
Provides condition monitoring
Provides more accurate data
Reduces equipment slows and stops
Reduces product waste
Delivers accurate data and reduced errors
Tracks raw materials and finished goods
Date and lot code accuracy for potential product recall
Allows robust tags to be embedded in totes, pallets, containers, and fixtures
Increases security with access control
Why is all of this important?
Converting a manufacturing process to a smart process will improve many aspects and cure pains that may have been encountered in the past. In the PFB industry, downtime can be very costly due to raw material having a short expiration date before it must be discarded. Therefore, overall equipment efficiency (OEE) is an integral part of any process within PFB. Simply put, OEE is the percentage of manufacturing time that is truly productive. Implementing improved controls architecture, automating change over processes, using networking devices that feature predictive maintenance, and incorporating RFID technology for traceability greatly improve OEE and reduce time spent troubleshooting to find a solution to a reoccurring problem.
Through IO-Link technology and smart devices connected to IO-Link, time spent searching for the root of a problem is greatly reduced thanks to continuous diagnostics and predictive maintenance. IO-Link systems alert operators to sensor malfunctions and when preventative maintenance is required.
Unlike preventative maintenance, which only captures 18% of machine failures and is based on a schedule, predictive maintenance relies on data to provide operators and controls personnel critical information on times when they may need to do maintenance in the future. This results in planned downtime which can be strategically scheduled around production runs, as opposed to unplanned downtime that comes with no warning and could disrupt a production run.
Reducing the time it takes to change over a machine to a different packaging size allows the process to finish the batch quicker than if a manual change over was used, which in turn means a shorter production run for that line. Automated change over allows the process to be exact every time and eliminates the risk of operator error due to more accurate positioning.
Traceability using RFID can be a very important part of the smart PFB factory. Utilizing RFID throughout the process —tracking of raw materials, finished goods, and totes leaving the facility — can greatly increase the efficiency and throughput of the process. RFID can even be applied to change part detection to identify if the correct equipment is being swapped in or out during change over.
Adding smart solutions to a PFB production line improves efficiency, increases output, minimizes downtime and saves money.
Digitalization does not stop at the packaging industry. There is a clear trend toward more individual packaging and special formats. What does this mean for packers and packaging machine manufacturers? The variants increase for every single packer, and this leads to a decreased batch size. The packer needs highly flexible machines, which he can easily adjust to the different formats and special variants. The machine manufacturer, in turn, must make these flexible machines available. What does this format change look like? Which technologies can support the packer optimally?
There are two different format adjustment tasks to perform. One is the adjustment of guide rails, side belts or link chains so that they can be adapted to the new format. The other is the changing of parts when a new format is to be produced.
Both tasks have different demands concerning automation technology and therefore there are different solutions available.
Format adjustment is the adjustment of guide rails, side belts or link chains. In order to carry out this adjustment quickly, safely and error-free, precise position information is required. This recorded position information can then be used to support manual adjustment on the display unit or it can be transferred to the PLC for fully automatic adjustment. One possible solution is to use different position measuring systems. Various standardized interfaces are available as transmission formats, including IO-Link.
IO-Link has ideal features that are predestined for format adjustment: sufficient speed, full access to all parameters, automatic configuration, and absolute transmission of measured values. This eliminates the need for time-consuming reference runs. Since the machine control remains permanently traceable, the effort for error-prone written paper documentation is also saved.
One example for a non-contact absolute position measuring system
A magnetic encoded position measuring system is ideally suited for position detection during format adjustment. It is insensitive to dust, dirt and moisture, offers high accuracy and a measuring length of up to 8,190 mm. Therefore, the position determination and the speed control during the change of guide rails, sidebands or link chains are no problem.
When changing to a different format size, it is often necessary to not only adjust guide rails but to also replace changeable parts. Machines are becoming more and more flexible, which means that the number of changeable parts per machine is growing. It is becoming increasingly difficult for the machine operator to find the right part and even more difficult to find the correct mounting position. This conceals some avoidable sources of error. If the replacement part is installed incorrectly, it can cause machine damage, which can lead to downtime.
Therefore, a fast recognition of changeable parts is all about reliably detecting the changeable part at the correct position in the machine. It is also important to make it as easy as possible for the operator to detect possible faults before they happen via a visualization system.
One way of identifying exchangeable parts is industrial identification with RFID.
The right part at the right position
When changing a machine over to a new format you can use RFID data carriers or barcodes to ensure that the correct new parts are being used. Vision sensors also detect whether the part was installed correctly or incorrectly. These solutions help you prevent errors and machine damage, which in turn increases throughput and reduces production costs.
Implement predictive maintenance
With RFID data carriers, the operating times of each change part can be documented directly on the part itself. If a part needs to be cleaned, replaced or reworked, a notification or alarm is issued in the machine controller before fault conditions can arise. RFID data carriers also allow regular cleaning cycles to be logged.
Automate machine settings
Since you can store the individual setting parameters for the change part on the data carrier, the part itself also provides the information to the machine controller. Thus, the change part can trigger a format change in the PLC and change the production process. This is an important step toward intelligent production in the Industry 4.0 concept.
With an LED signal lamp, the operator can recognize the operating status of the machine quickly, easily and at a glance. Among other things, it serves to monitor the operating windows and signals whether all settings have been made correctly. The segments of the signal lamp can be configured so that one machine lamp meets a wide range of requirements.
Format adjustment involves changing guide rails, sidebands or link chains due to a new format. This can be semi-automated or fully automated on the machines. It requires displacement measuring systems whose sensors provide feedback on the respective position.
If format parts on the machine have to be replaced, it must be ensured that the correct changeable part is installed at the correct position in the machine. Industrial identification systems such as RFID are suitable for this purpose. Each changeable part is equipped with a tag and, with the help of the read/write heads, it recognizes whether the correct changeable part is installed in the correct place.
Both automation options offer the following advantages:
Short set-up times and increased system productivity
Efficient error prevention
Increased machine flexibility
Avoidance of machine damage due to wrong parts when starting up the machine
Both washdown and hygienic design are common terms used in the food and beverage industry, and are increasingly being used in the packaging industry. These terms are used in different scenarios and easily confused with each other. What exactly are the differences between them, and in what applications are each used?
Why are hygienic design and washdown needed?
The consumer, and more specifically, the health of the consumer is the core concern of the food and beverage industry. Contaminated food can pose a danger to life and limb. A product recall damages the image of a company, costs a lot of money and as a worst case scenario can lead to the complete closing of the company. To prevent such scenarios, a producers primary objective is to make sure that the food is safe and risk-free for the consumer.
In food manufacturing and packaging plants, a differentiation is made between the food area (in direct contact with the product), the spray area (product-related) and the non-food area. The requirements of the machine components are different depending on which area they are in.
The Food Area
In the food area the food is unpacked, or partially unpacked, and particularly susceptible to contamination. All components and parts that may come in contact with the food must not adversely affect this, e.g. in terms of taste and tolerability.
The following needs to be considered to avoid contamination:
Hygiene in production
Use of food contact materials
Food-grade equipment in Hygienic Design
These requirements result in the need for components that follow the hygienic design rules. If the component supplier fulfills these rules, the machine manufacturer can use the components and the producer can use the machines without hesitation.
Many component suppliers offer different solutions for hygienic design and each supplier interprets the design differently. So what does hygienic design mean? What must be included and which certifications are the right ones?
The material used must be FoodContact Material (FCM). This means that the material is non-corrosive, non-absorbent and non-contaminating, disinfectable, pasteurisable and sterilizable.
Seals must be present to prevent the ingress of microorganisms.
The risk of part loss must be minimized.
Smooth surfaces with a radius of < 0.8 μm are permitted.
There must be no defects, folds, breaks, cracks, crevices, injection-molded seams, or joints, even with material transitions.
There must be no holes or depressions and no corners of 90°.
The minimum radius should be 3 mm.
Supporting institutions and related certifications
There are different institutions which confirm and verify the fulfillment of these rules. They also support the companies during the development process.
EHEDG – The European Hygienic Engineering and Design Group offers machine builders and component suppliers the possibility to evaluate and certify their products according to Hygienic Design requirements.
3A – 3-A Sanitary Standards, Inc. (3-A SSI) is an independent, non-profit corporation in the U.S. for the purpose of improving hygiene design in the food, beverage and pharmaceutical industries. The 3-A guidelines are intended for the design, manufacture and cleaning of the daily food accessories used in handling, manufacturing and packaging of edible products with high hygiene requirements.
FDA – The Food and Drug Administration is a federal agency of the United States Department of Health and Human Services, one of the United States federal executive departments. Among other things, the FDA is responsible for food safety.
What does a hygienic design product look like?
Below is an example of a hygienic design product.
Stainless steel housing VA 1.4404
Protection class IP69K (IEC 60529)
Active surface made of PEEK
Since the product contacting area is associated with high costs for the plant manufacturer and the operator, it’s beneficial to keep it as small as possible.
The Spray Area
In the spray area, there are different requirements than in the food area.
Depending on the type of food that is processed, a further distinction is made between dry and wet areas.
Here we are talking about the washdown area. Washdown capable areas are designed for the special environmental conditions and the corresponding cleaning processes.
Components which fulfill washdown requirements usually have the following features:
Cleaning agent/corrosion resistant materials (often even food compliant, but this is not a must)
High protection class (usually IP 67 and IP 69K)
Resistant to cleaning agents
Ecolab and Diversey are two well-known companies whose cleaning agents are used for appropriate tests:
Ecolab Inc. and Diversey Inc. are US based manufacturers of cleaning agents for the food and beverage industry. Both companies offer certification of equipment’s resistance to cleaning agents. These certificates are not prescribed by law and are frequently used in the segments as proof of stability.
The washdown component must also be easy and safe to clean. However, unlike the hygienic design, fixing holes, edges and threads are permitted here.
In many industries, especially in Packaging, the need to minimize capital equipment costs drives engineers to implement low-cost, manual methods of size change (also called format change) on their machinery. In most cases, this means hand-driven cranks with mechanical dial pointers and/or mechanical revolution counters.
While cost is saved on the procurement side, cost is also shifted over to the operational side. Plant management is left with the task of keeping accurate records of various machine set-ups needed to run different products, as well as the task of training machine operators to perform all machine set-ups correctly. It doesn’t always go as smoothly as expected, and machine reformatting can result in longer downtime than planned, machine stoppages, and possibly excessive scrap.
The key to size-change improvement is capturing the linear movements of the machine components and bringing them into the control system, and then providing “smart” visual feedback to the machine operator during setup. For capturing machine position, a robust and cost-effective magnetic linear encoder is ideal. However, traditional linear encoders deliver an A-B quadrature incremental signal, which requires re-homing upon start-up or after a power loss. What’s needed is an absolute encoder signal, but that brings other challenges such as the cost and complexity of implementing an absolute signal like SSI (Synchronous Serial Interface).
Fortunately, there’s a new encoder interface option that eliminates the problem of non-absolute feedback and the hassle of absolute position signal interface: IO-Link. IO-Link is a multi-vendor, non-proprietary, device-level serial digital interface that can be aggregated onto today’s Ethernet industrial networks. Magnetic linear encoders are now available that feature absolute position indication combined with the ease and convenience of the IO-Link communication protocol.
Now we just need to provide visual feedback to the machine operator regarding which direction and how far to turn the hand cranks. Once again, IO-Link provides the answer in the form of an IO-Link-enabled, fully programmable multi-segment LED stack light. When a new machine set up is required, the position parameters are stored in the controller. The controller communicates over IO-Link to the LED stack lights, indicating to the operator which dials need to be turned and in which direction. For example, a horizontally mounted stack light could be lit red on the right half, indicating that the dial needs to be turned to the right. As the position moves closer to the proper setting, the red segments count down until the entire stack light goes green, indicating that the correct position for that axis has been reached. No paper records to maintain and store, and very little training required with the intuitive operator visualization.
For more information about IO-Link linear encoders click here, and to learn more about IO-Link programmable LED stack lights visit www.balluff.com.
When referring to pneumatic cylinders, we are seeing a need for reduced cylinder and sensor sizes. This is becoming a requirement in many medical, semiconductor, packaging, and machine tool applications due to space constraints and where low mass is needed throughout the assembly process.
These miniature cylinder applications are typically implemented into light-to-medium duty applications with lower air pressures with the main focus being precision sensing with maximum repeatability. For example, in many semiconductor applications, the details
and tolerances are much tighter and more controlled than say, a muffler manufacturer that uses much more robust equipment with slower cycle times. In some cases, manufacturing facilities will have several smaller sub-assemblies that feed into the main assembly line. These sub-assemblies can have several miniature pneumatic cylinders as part of the process. Another key advantage miniature cylinders offer is quieter operation due to lower air pressures, making the work place much safer for the machine operators and maintenance technicians. With projected growth in medical and semiconductor markets, there will certainly be a major need for miniature assembly processes including cylinders, solenoids, and actuators used with miniature sensors.
One commonality with miniature cylinders is they require the reliable wear-free position detection available from magnetic field sensors. These sensors are miniature in size, however offer the same reliable technology as the full-size sensors commonly used in larger assemblies. Miniature magnetic field sensors play a key role as speed, precision, and weight all come into play. The sensors are integrated into these small assemblies with the same importance as the cylinder itself. Highly accurate switching points with high precision and high repeatability are mandatory requirements for such assembly processes.
To learn more about miniature magnetic field sensors visit www.balluff.com.
In the design of automation equipment everyone is looking for an edge. How can I make parts faster or easier or safer? I’m sure you don’t encounter the need for 360 degree rotation everyday; but when you do, it can become a pain to maintain sensor and actuator information or even a network connection.
There are two different ways to maintain your connection in a rotation application:
In last month’s discussion “Automatic Size Change on a Budget – Part I”, we talked about the designer’s dilemma: accomplish size change at low-cost with an unsophisticated manual size change mechanism, or achieve high-performance automatic size change using costly servo drives. This month we will look at some alternatives that nicely bridge the gap between affordability and automatic (or, semi-automatic) operation.