In the latest AIM podcast episode by Magnum Systems, Mike Abare interviews Wayne Revell, an application engineer with deep expertise in packaging. They focus on the complexities of valve-bag sealing, exploring its importance in securely packaging various products, from minerals to food, and the evolution from traditional to advanced ultrasonic sealing techniques. While discussing the benefits and challenges of these methods, including cost and production rates, they also examine the role of automation and collaboration with bag suppliers for optimal performance. The conversation includes insights on selecting the appropriate sealing method for enhancing operational efficiency, ensuring product safety, and meeting environmental standards. It also emphasizes Magnum Systems’ dedication to innovative solutions and customer support in the packaging industry.
Transcript
Mike Abare:
Welcome to Magnum Systems Podcast, where we'll aim to dive deep into the world of A for automate, I for integrate, and M for manufacture. I'm your host Mike Abare, and I'll be bringing you expert interviews, thought-provoking discussions, and real-world case studies that shed light on the latest trends and developments in systems integration. Whether you're a seasoned professional who's seen it all or just curious about manufacturers who are revolutionizing their operations, this podcast is your one-source resource. So sit back and relax as we aim to cover all the challenges automation and integration are solving today. Let's do this.
Welcome everybody. Thank you for attending this session of Magnum's podcast. Today we have a guest from Magnum Systems with us. Wayne, would you take a moment to introduce yourself?
Wayne Revell:
Hello. I'm Wayne Revell, and I am glad to be here for this podcast. I'm an application engineer at Magnum Systems, primarily focused on the packaging side.
Mike Abare:
Wayne has been with Magnum Systems for several decades and brings a certain level of expertise to us. Today, we're going to talk about the topic of sealing valve bags. Sealing bags in the packaging industry is not anything new, but when we get into the sealing of valve bags, there are some uniqueness or variances that we felt would be a good topic to cover today to dispel any misbeliefs or misconceptions about the sealing of valve bags.
Wayne Revell:
That's correct, Mike. We have a lot of customers who ask questions about sealing valve bags because it's common for us to seal open-mouth bags, but valve bags are a different type of product and normally don't have a solid seal or a protected seal.
Mike Abare:
So we should start at the beginning, the basics. What is a valve bag?
Wayne Revell:
A valve bag, in general, is a paper bag that has a spouted opening that slides onto a tube. The product is either forced into the tube by an auger or an air packer, and the bag fills through that opening. The bag in general, the original design and the common design is that the seal is a passive seal on the inside that the product helps hold closed.
Mike Abare:
So the bag has a passive seal. Why would the user want a bag valve that could be sealed?
Wayne Revell:
The passive seal holds the bag closed as long as the product is against it, but it still could allow ingress or egress of something into the bag or leak out of the bag. A lot of customers are not satisfied with their products being displayed and product leaking out onto the display floor in their business, or they simply don't want someone to be able to introduce something into the bag after the point of filling it that might contaminate the product in the bag.
Mike Abare:
Safety and cross-contamination issues.
Wayne Revell:
Correct.
Mike Abare:
And I trust that oftentimes these could be consumables for humans or animals or things like that.
Wayne Revell:
Yeah. Valve bags are traditionally used for many products, such as minerals and cement. But there are many options for using valve bags for foodstuffs, and sometimes, filling valve bags is preferred over filling an open-mouth bag because they palletize better being a blockier-shaped bag than a sewn or sealed open-mouth bag.
Mike Abare:
So what methods exist to seal a valve bag?
Wayne Revell:
Commonly, the simplest method that existed the longest was still a passive seal. This was like an extended crepe paper sleeve that stuck out on it, and they called it a tuck-in sleeve. The person that filled the bag would then also fold the sleeve and tuck it into the end of the bag spout, and that would provide a more leakproof seal. But it wasn't sealed, you could open it and still introduce something into it if you wanted to. Over the years, the extended sleeves that are made out of crepe have been changed to different types of products, and the more common way to seal a bag nowadays is with an ultrasonic sealer that uses an extended sleeve that has some poly plastic on the inside of it. The ultrasonic seal machine makes the plastic bind together. However, the interior of that sleeve could just as easily be pre-applied glue, and a heat jaw sealer could be used to close it. There are plastic valve bags, and those could be sealed by a heat jaw sealer also.
Mike Abare:
So does the valve of the bag need glue or sealer applied to make it actually seal?
Wayne Revell:
If it's a plastic sleeve, it doesn't have to have glue. Either heat or ultrasonic sound will cause the molecular structure of the plastic to change or the plastic to melt and glue together. But it could also have a pre-applied glue and heat to make the glue reactivate and go together.
Mike Abare:
You mentioned ultrasonic bag sealing. What are the advantages and disadvantages of this type of sealing application?
Wayne Revell:
Magnum Systems makes a valve bag sealer that is an ultrasonic-based sealer for all of our valve-filling machines. And the advantage is that it doesn't use traditional heat. So the seal is made by high frequency sound and the amplified high frequency sound drives the product away from the sealing area and also causes the plastic to bond itself together. An advantage of that is that it doesn't have the heat, so on some products that's a benefit. You don't get a burnt area there or danger so much with possibly an explosive or flammable product. But the downsides of it are cost and rate. The cost is quite a bit and the bags per minute will probably be between two and three bags per minute, per spout. So, if you're doing a process where you have high production, it would slow you down a lot to do the seal.
Mike Abare:
Certainly, they've got to set in mind, as far as bags per minute, what rate they're trying to achieve. Would this essentially keep them from selecting ultrasonic sealing if it didn't meet the rate requirements?
Wayne Revell:
That's a good question, too. We can use multiple spouts and we can automate the system so that there's a robot or a device to place the bags on the spout. The multiple spouts can increase the production backup up to an acceptable level. But again, adding spouts and machinery is cost and sometimes the cost is not justified for the product.
Mike Abare:
Now there are concerns about the installation of ultrasonic sealing as far as in hazardous areas or with hazardous materials and the packaging of those hazardous materials.
Wayne Revell:
That's true. We have a lot of requests for packaging products that could be flammable or could be combustible or could cause an explosion if there was a spark or an event that caused them to combust. And in those applications, usually there's a class division electrical rating that needs to be met and adhered to for the area that that product is packaged in. The ultrasonic sealing that we are able to use does not have an actual class/div rating on it, so it is a concern and it would require that the customer and the user, whoever is using the product in that location, figure out if they can get a variance or an acceptance to use this equipment in that area. We can upgrade the electrical components primarily to meet the area, but the actual horn or amplifier does not have any rating, so as an unrated device, it won't really meet the class division area ratings that it might be trying to be applied in.
Mike Abare:
Is ultrasonic bag sealing safe to operate?
Wayne Revell:
From the standpoint of using it in an explosive or a combustible environment, I consider it safe and most of our customers that have applied it in this way consider it safe because it isn't really generating heat. As long as you can control most of the electrical current and devices that are related to it into enclosures that are rated, that works well for the area. Another aspect might be that there's a lot of moving parts on an ultrasonic sealing device. We have a lot of components on the machine. We have components to try to keep the bag in an upright position, in the same height, move it out the same way, position it so the jaw of the sealer will seal the valve in the same way every time and keep the valve clean. And all those moving components would be somewhat hazardous to a person if they were trying to do the process manually. We generally use ultrasonic sealers with automation, but we have done some manual operations.
Mike Abare:
Are there applications where changing away from a valve bag might be more practical?
Wayne Revell:
That's absolutely true. We try to look at each application that a customer brings to us and just because they're asking for a valve bag or traditionally have been in a valve bag, we probably make equipment that would package powdery aerated powders in a much better way in an open mouth bag. Some of the time this is possible and some of the time it isn't. The market that the customer sells in may not accept a different style of bag. In certain instances, we would try to change them to an open-mouth bag because we could use deaeration probe to settle a product and remove the air from the product and we can get an easier seal. There's also a cost saving to go to an open-mouth product if they can accept it in their market and if it will still provide a package that they can ship correctly.
Mike Abare:
So there are alternatives, so a customer shouldn't feel rat-holed into a valve bag, it's just a matter of making sure that it works with their process or what they're trying to achieve in the marketplace?
Wayne Revell:
Yeah. We find that each application has a number of variables that play into why the customer chooses the type of package. In general, we can offer open-mouth bags or valve bags for about any application. Our fillers will work on products that go into those style bags, and we can try to help the customer choose the best path for marketing their product and still provide the product safety they want from a seal.
Mike Abare:
So you mentioned earlier that valve bags could be paper or plastic. Are there other types of valve bags or other materials used for valve bags, or are paper and plastic the only options out there?
Wayne Revell:
Normally, they're a craft paper, and normally, bags in general are a craft paper, but there are certainly different thicknesses and types of craft paper. A lot of craft paper bags have a laminate poly layer inside of them and that would be a typical design. Also, the craft paper bags might be one-ply or two-ply, or three-ply, depending on the strength of the bag and what it needs to do. But there are options to paper and we can seal on our sealing equipment. Any bag that is of conventional paper bag, valve bag design. In other words, we want it to have a flat top that folds out and has a flat spout extension that we can slide onto the spout and then seal that extension. We are familiar with plastic bags that are called an R-style and they cannot really be sealed on any machine. They're made for an inexpensive product container and they just don't have the features needed to have that extended sleeve that we need to seal.
Mike Abare:
So there are valve bags that exist that really are not good candidates for ultrasonic sealing then?
Wayne Revell:
That's correct. Those plastic valve bags that are very inexpensive style are not good for ultrasonic or any other sealing because they don't have that extended tube sleeve.
Mike Abare:
How often or how important is it that we get the customer and the bag vendor supplier in a conversation with us so we can make sure we understand what is truly going to work in that application?
Wayne Revell:
One of our first concerns always is to try to get sample bags from a customer if they're doing something already. Then, we do offer help with valve bag vendors, or we'll work with their current vendor to modify the bags. They have to work well on our machine, especially if there are automation bags that are used in automated systems. They need to be of automation quality because the automated robots are simply performing a repetitive task, and they can't do the subtle things a human can do to ensure every bag will be placed.
Mike Abare:
Can a packaging system with an ultrasonic sealer be automated? I know the answer to that. Can you expand on that though? And again, what are some of the challenges or issues with automating a valve bag with an ultrasonic sealer?
Wayne Revell:
So the answer obviously is that almost anything can be automated in some way. We offer automation to pick up the empty bag and put it on the spout. We offer automation to transfer the filled bag to a pallet and stack it. The entire process can happen without a human actually touching the bag other than to place stacks of empty bags in the bag-placing machine. But I think the question is more about whether this application is smart to automate. If it has a lot of complexity in what the people are doing in their current roles, or if the product doesn't fill the bag the same every time, it varies in bulk density a lot or is extremely dirty and makes a lot of dust in the area.
I mentioned earlier that valve bag seals on an ultrasonic sealer could be cleaned by the vibration of the amplifier during the seal, but it won't clean out an extensive amount of product. So a little bit of dust is one thing. A layer of product is another thing and the seal won’t be good if the product is too dirty. So this is a complex question. Automation is something that we try to look at every aspect of with our customer and try to make sure that it really makes sense to spend the money on automation, and if they're going to get a reward back from it that's cost-effective.
Mike Abare:
Does Magnum Systems make other types of sealers for valve bags?
Wayne Revell:
Magnum Systems doesn't make sealers for valve bags except for the ultrasonic sealer, and that's actually a purchased component. The ultrasonic sealer itself is a purchased component that we fit into our equipment. So, in general, we don't make bag sealers at all. But to answer the question more specifically, you conceal a bag with a foot-operated jaw sealer just by getting that extended sleeve into the jaw. But that would require a person to take the bag off the spout, set it in another position, insert the sleeve into the jaw and then seal it. You can also buy aftermarket small handheld jaw sealers that, in a lot of cases, can seal a bag also, provided the glue and the material that we're sealing is something the heat range of that little jaw sealer can overcome and make a seal with.
Mike Abare:
So if I'm a customer that's using valve bags, it sounds like it's certainly important to work with a company like Magnum Systems to really get down into the fact-finding data collection of, like you said, the various bag sizes, the bag types and, ultimately, what the customer's trying to achieve. It sounds like certainly, the product they want to package will have some impact on that, but unless we have a class electrical issue, ultrasonic sealers are a pretty flexible type of machine that can be used across valve bags as a general statement.
Wayne Revell:
Yeah. Ultrasonic sealers can be used on any of the types of machines we make that fill by valve. We make impeller packers, air packers and auger packers that can fill product into a valve bag. We just want to have the bag and the valve sized so the rate can be achieved that the customer expects. We don't want to over-promise a rate that the sealer itself may slow down. We want to look at every application from the standpoints you said. What bag do they need? What ultimately do they want that package to prevent from happening or protect the product from? What is the product, and will it be sealed in a bag? Will it have a lot of untrained air that can cause a problem, or will it be very dirty and cause a problem with the seal? We work through those points of the application before we say that sealing a valve bag is the perfect solution.
Mike Abare:
Help pull all of this together. If there was a single statement or a single thought that says, "Here's the benefit or the value of using sealers for valve bags," what would that look like?
Wayne Revell:
The benefit, no doubt, is that the same thing that customers are asking for: either it seals the product in so it doesn't become messy in handling the pallets, or it prevents something from getting into the bag that you don't want in the bag. One of the questions we always are asked is, "Can we do this?" And being in the industry for as long as I've been, I always reply to the customer, "Ultrasonic sealer can do what they want, but it's going to cost more than the packaging machine did and it's going to reduce them by a couple of bags a minute." Usually those are my primary two questions to help determine if we proceed with the inquiry or not. Because if the customer can't tolerate either one of those two questions, then it doesn't really turn into a cost-effective solution for them.
Mike Abare:
So it's important to qualify what the customer's target is?
Wayne Revell:
There's no reason to waste the customer's time leading them down the road of something they can't afford to put into place.
Mike Abare:
Or doesn't apply to their situation.
Wayne Revell:
Yeah. Budget is always the third most important point of our process with a customer in trying to determine what equipment they would purchase.
Mike Abare:
Customers believe that the valve itself creates a satisfactory seal, and that may be acceptable for some applications. But there are others where safety, cross contamination and other challenging issues make valve bag sealing an important part of that process. So thank you for coming in and expanding on that. We really would like to encourage our listeners that if you have questions about sealing valve bags, please reach out to Magnum Systems and we'll address those questions for you.
Wayne Revell:
Certainly. If you need to talk about this, get with one of our regional managers, they'll set up a Teams call and we can talk through your application.
Mike Abare:
Thank you, Wayne, for coming in today.
Wayne Revell:
You're welcome. I appreciate being here.
Mike Abare:
And that's a wrap for this episode of AIM. Thanks for listening and thanks for joining us today. If you have any questions or you would like to learn more about the topic we discussed today, feel free to reach out to us on our website or social media channels, so you never miss an episode packed with valuable insights. Please join us next time as we continue to explore the ever-evolving landscape of systems integration. Until then, keep aiming for success. This is Mike Abare signing off. Good day.
