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On behalf of Parker Hannifin's Engineer Materials Group, welcome to our Webinar regarding customization of integral seals specifically for EV driveline applications. This is John Van Zummeren speaking. I am a global account manager with Parker Hannifin with over five years of experience specifically targeting the E-Mobility space. I'm also here with Jay Jones.
Hello, everyone. Thank you for joining today's tech call. My name is Jay Jones, and I've been in the seal design business for the past 30 years, and currently I'm the product design engineering manager for Composite Sealing Systems Division, located in San Diego, California. My design team and I work with the automotive design engineers to understand your challenging application parameters and performance objectives to collectively solve your challenging static face seal specific to your application.
Thanks, Jay. In today's presentation, I will be tossing it over to Jay several times. He'll first start with some engineering basics. This will involve sealing principles and materials of construction. We will also run through some application advantages, some of which are inherent to the design as well as the customization features we bring. Jay will then toss it back to myself and review some of the success stories and applications we currently have in the EV space, where we were able to help some of our customers.
So who is Parker CSS? As Jay mentioned, CSS stands for Composite Sealing Systems Division. This division is part of the Parker Engineer Materials Group. It is based out of San Diego, California. The engineering and technical support is also based out of San Diego, California, and all products today we discuss will be manufactured in our Baja, Mexico facility just across the border.
Here are a couple of examples of some products the CSS division sells inside of the EV space, including EV inverter seals, electronic drive units. Both of these are examples of Integral Seals™.
We also have capabilities in battery and inverter housing seals. And then up in the top left hand corner are what we refer to as a slimline, which go on the ends of connections for HVAC and battery cooling systems. I will now be talking it over to Jay and he will be running through some basic engineering principles for Integral Seals™.
Thank you, John. As John stated, first, we're going to go over some of the basic design considerations when we're working on these new applications in the EV market, and our particular focus is going to be what Parker calls integral seals are also known in the industry as edge bonded seals.
This slide I wanted to basically show you the composition of what an integral seal is. It's comprised of basically three components, a rubber or an elastomeric sealing unit and a layer of bond, and a retainer. As you can see in the lower left, the retainer typically are either steel aluminum. It could be any other material, or it could be an injection molded plastic with metal compression limiters in it. And these retainers are made by either laser cut, which typically is in a prototype process for rapid turnaround, or stamps in production for high volume or machined. Or sometimes we could 3D print it if it's feasible. And we've also done powdered metal and sintered metal. And the bond is typically either sprayed, dipped, or brushed prior to doing our over-molding of the rubber.
So we begin each seal design project by collecting the customer design inputs. It's crucial that we fully understand the specifics of your operating environment where the seal is intended to function. In order to select the appropriate elastomer for your given application, there are four key inputs that we need: that's the media to be sealed, the maximum operating temperatures, the Max operating pressure, and if it's steady or does it cycle off and on pulsing, and at what's time anticipated that the system will operate at those peak temperatures.
There are three key fundamentals that make our integral seal so successful. Number one is squeeze or compression. Number two is resilience. Number three is alternative load path.
Let's start with fundamental number one, squeeze or compression. The squeeze is what creates the intimate contact between the seal and the mating hardware, thus preventing any joint leakage. If the mating hardware has some surface imperfections or asparities, it can sometimes overcome those potential leak paths by increasing the amount of squeeze on the seal bead. However, it's determining a balance between the amount of squeeze and a particular elastomer that can withstand without exceeding its tensile stress capabilities, which may cause it to self destruct or split.
The picture there shows what the initial seal looks like prior to installing it into the application. And the second one, is the FEA showing it at full compression.
Fundamental Number Two or resilience. It's basically the seal's ability to bounce back close to what its original shape was once you assemble it and it goes through the operating parameters and then you disassemble it and take it back out. What does that spring back look like. That's what resilience is. And it's important to ensure that the seal is still performing like an energized spring, as you see there in the picture, because it's pushing or sealing against mating hardware at all times throughout the product lifecycle.
Fundamental Number. Three Alternative Load Path. The CSS integral seals provide what we refer to as an alternate load path that ensures that there's always a metal to metal column of contact, transferring the clamp load and preventing over-compression of the seal, which leads to the seals squeezing out, which in turn turns to torque loss, and then it could be a leaky joint and possibly full equipment failure. We achieve this alternate low path by implementing a metal retainer or a seal with a metal compression limiter.
So how does an integral work? Well, once an integral seal is fully compressed in the application joint, it can be thought of as having a stored, coiled, spring-like energy, creating a sealing for us, which I referenced in the previous slide, and it presses against the two halves of the mating hardware. The sealing force is further increased as pressure, as you see there in P1, hits the seal. It pushes against what you see in the blue area, and then it forces that spring to kind of open up and increases your contact pressure. That's increasing your sealing force against the hardware.
The chosen retainer thickness and seal height are specifically designed to target an ideal amount of compression for a given situation.
Now let's talk about some of the integral seal application advantages.
CSS has many custom design integral seal cross sections. as you see here. These are the more common ones. We do have others that are more customized, but these are the key ones that we use over and over. The two most frequently used designs are the full circular and oval D shaped ones you see it there at the top right, and they both provide excellent sealing while requiring a low closure force or a bolting system. We have used that square or hammerhead when you see there the third one down from the top. This cross section with specific elastomers and applications where the mating hardware may contain imperfections like pit porosity or heavy machining marks from rough machining. However, keep in mind this cross section requires a higher closure force or clamp load to close the joint.
The dual seal is often used for customers who desire redundant sealing or wish to protect their mating hardware surface finish, such as if we have an aggressive media. We've seen this in some applications where it actually attacks the metal, but everywhere where the sealing the last one was, it was shiny clean. So sometimes that's a desirable feature where a customer wants to add an extra seal bead. We can also add what we refer to as dams in between those dual beads, and we put them intermittently along the seal path. And what that does, it contains or prevents any potential leak that may occur from spreading or flowing elsewhere. It keeps it contained between those dams.
In this slide, the message I want to convey is that we also could do an ID/OD seal if that would be beneficial for your application. Such as we could be sealing pressure on one side and keep sealing the environment out on the other side. As long as they're sufficient mating hardware land, we can accommodate both beads.
One of the most significant advantage of the integral seal is that we can combine multiple ports as you see there into one seal plate or one single plate while still providing robust sealing across differential pressure ports. They also eliminate the need for our customers to machine any grooves into their hardware, providing a quick, mess-free and easy installation.
This slide is what we refer to as PIA or parts and assembly. We can incorporate other desirable features to assist in your manufacturing assembly lines. An example of this is adding that rubber feature you see there in two or more bolt holes. Sometimes you may want just two for alignment. Other times you may want to do all of those features in all the holes, so it allows you to do like a pre-build before going into the full assembly line.
This ensures that the seal location is accurate. It improves the tolerance stack ups and allows sub assemblies, as I stated, to be built to reduce your final assembly times. An additional benefit is that these features can simplify assembly in challenging hardware situations, such as a vertical or upside down assembly on your line.
These are just some additional special features that we've used in the past I wanted to share, such as if you wanted to locate the seal with pins, we can either do an all rubber pin or we can form the metal such as you see there and then mold around it to make it more rigid, more robust.
And secondly, we can put bent metal features you see on the right. That one in particular was to guide push rods or just help hold something in position while something else is bolted to it. In the bottom right one we can form pockets and different features just all rubber. In that particular one is for a pocket for RTV.
This is kind of a unique one that we came up with a number of years ago, so we called the alternative integral seal. It's all rubber so it doesn't have a metal backbone or plastic. It's all rubber. But we used metal compression limiters. And mainly these are for low pressure systems and typically used in very large applications like tank lid covers. Sometimes these range up to four or five feet by three to four feet wide. And the beauty of this one also, as you can see in the top left, we can design it so it's really robust. It can compensate for out of flat sealing surfaces or step surfaces as shown there. And also in packaging, you can roll these up and put them on a mandrel or something. You don't have to ship in big boxes is my point, which drives shipping costs.
I'll turn it over to John.
Thanks Jay. I appreciate all the wonderful technical information there. I will now run over a couple success stories and current applications we are selling in the EV space.
For one OEM, we were able to design a custom drivetrain cover. For this cover, we replaced an all rubber component. Our OEM received improved assembly time and takt time as well as a complete package cost savings from the elimination of the machine grooves. Parker was able to support throughout the entire process. That being the design. The FEA as well as prototype builds. We also help develop and test the DVP&R for material and compatibility.
Similarly, with a different OEM, we worked on a battery housing channel. This channel was able to cover large amounts of gaps while still being able to maintain its flexibility through cantilever flanges. Similarly to the drivetrain component, we supported throughout the entire process; being design, 3D FEA, prototypes as well as the DVP&R. We like to have that type of process and support throughout all of our programs that we work with with our customers here at Parker.
Lastly, Jay and I will give a full summary. There's been a lot of information provided today. We will review all the benefits that Jay mentioned in the next slide.
Thanks, John. Appreciate that. In this slide, we just want to go over once again, what the advantage of the integral seals are; what are the key benefits.?
One is the controlled squeeze, robust static compression. It provides a metal to metal contact, the alternate load path we spoke about, which ensures there's no retorquing required.
It can accommodate multiple seals all in one plate called multiple port sealing.
It's reusable typically, so if you have a service need for something, you have to take it apart and reassemble it. You can reuse it.
It's quick, easy visual confirmation that the seal is installed because of the thickness of the retainer, you can see it from the side.
It eliminates the need for machined grooves that typically have tight tolerances that have to be maintained.
We can accommodate other things in your operation by adding special features to assist in your assembly.
And it's also robotic installation friendly with a rigid retainer.
And finally, there's no flange clean up required when replacing it.
Thanks again for joining us on this webinar. There's been a lot of information provided, so Jay and I have provided our contact information below. If you have any questions regarding CSS products, Integral seals, or any Parker Hannifin engineered product, please feel free to reach out to us. Or go on our website at Parker. com/css. We have also provided an email for CSS support for additional questions to be answered. Thanks.
