On-Demand Webinar:  High Performance Metal Seals for Aerospace and PowerGen Gas Turbine Applications

Thanks, Jon. I appreciate everyone joining us today. My name is Ricky Pickles . I'm the global account manager for Aero and Military Engines, and I'm joined by Jeff Pappalardo, who is the business development manager for PowerGen gas turbines. Today, we're going to cover a wide array of an agenda, we're going to start with the standard seal design, move to E-seals, C-seals. We'll talk about our seal materials that we have available, some air ducts, and then we'll open it up for questions and answers.

So who is Parker CSS? Parker is a very large corporation with many divisions, and in one of these divisions, the Advanced business Unit focuses solely on metal seals. The business unit is located in North Haven, Connecticut. And these seals are used for high temperature, high pressure applications that are critical. So before moving to standard seal designs, we're going to launch our first poll question when designing a high temperature seal, do you use a supplier catalog, use the Internet or contact your supplier?

We'll give you a few seconds to answer this. All right, thank you, everyone. And moving back into our presentation.

Here you can see a wide variety of different cross sections that we have. Each cross section has unique characteristics that should be considered when designing for your application. This diagram shows the inverse relationship between load and leakage. On the left hand side, we have a spring energized C-seal, which is great for extremely high loads and very low leakage.

All the way to the right, you can see a cross section of one of our E-seals, which provides very low load and moderate leakage. The table displays different characteristics we take into account to align with your application priorities. For example, if your joint has very high thermal movement and requires a low load against your mating hardware, our best option is an E-ring. E-rings and C-seals are the most commonly used designs in gas turbines. And I'll hand it over to Jeff to discuss these in more detail.

Thank you, Ricki. As you said, because E-seals and C-seals are the most commonly used compliant seals for gas turbines, I'm going to discuss these in more detail.

Casing flanges and high gas path turbine sections are the primary applications for E-seals in PowerGen engines. Casing seals, typically made of Inconel 718, are used to prevent horizontal and vertical flange leakages caused by thermal separation at these joints. They are shaped to follow the bolt pattern and will have caps applied at the seal ends to reduce leakages around those ends.

One of Parker's gas turbine customers was actually able to reduce the total casing cost by installing our casing E-seals. They actually reduced the usage of some very expensive casing bolts knowing there could be some potential leaks. However, by adding the casing E-seals, they prevented these leaks. Overall, the seals were much less expensive than the bolts they removed.

Turbine section seals are 360 degree seals that are often segmented into 90 or 180 degrees due to the large size of the turbine sections. They are usually installed in closed cavities and that can be very challenging. The seals can be pre-compressed with an epoxy to a free height, less than cavity depth. The epoxy will burn off when the turbine reaches the operating temperature, allowing the seal to open up and seal the joints. Pre-compressed seals have provided long term savings from several Parker's customers.

When seal segments are installed in the closed cavities, the resistance is very strong. Mechanics are trying to push these long seal segments into grooves that are actually smaller than the seal. The result is long assembly times, often damage to the new seals. Parker's pre-compressed seals greatly reduce assembly time and also eliminate new seals having to be replaced due to installation damage, due to high vibration, and large cavity movement in the turbine section. Our E-seals are often coated with Tri-com® or T800 for wear protection.

For Aerospace engines, Inconel 718 and Waspaloy are the primary alloys used depending on the temperature of the application. Because aero engines are smaller than PowerGen engines, the E-seals are usually full hoops or contain a single split. These seals will also be coated with TriCom or T800 for wear protection. Other applications for E-seals are in aero engines AS1895/7 and /23 for V-band joints.

Parker's AS1895/7 and /23 E-seals are industry standard designs to match the AS1895 flanges and range from one inch to seven and a half inches. They're usually unplated Inconel 718 seals that are solution annealed and age hardened that can be made with Waspaloy or Rene 41 for extreme temperature applications.

Because of the complexity of gas turbine applications, Parker has many different types of E-seals. These are pre-compressed seals cells to simplify installation. We have hundreds of different cross sections to match the application sizes and requirements. We can make axial facing and shape these seals as well. And we even make double E-seals with connecter bands to bridge across joint gaps. This is why we encourage you to contact Parker for assistance in seal design when working with E-seals.

Now on to C-rings. For PowerGen gas turbines, the two primary uses for C-rings are horizontal and vertical casing joint applications and fuel nozzles. For the casing seal applications, spring energized C-rings are an alternative to E-Seals when flange separation is not as extreme. A large cross-section spring energized C-ring can have a spring back up to .8 millimeters, whereas E seals can spring back to about eight millimeters. The advantage of the spring energized C-ring over an E-seal, however, is higher load, resulting in much lower leakage than an E-seal.

For flange seal nozzle assembly, C-rings along with spring energized C-rings are often used to seal at the flange area. Some fuel nozzle assemblies use braised joints, but for the flange nozzles, seals are required. The C-rings are typically plated in silver and when silver is not allowed, copper and nickel can be used.

For aerospace engine fuel nozzle,s because of their smaller sizes and challenges with machining a groove, we typically use C-rings with limiter plates or retainers to mate with the flanges. The retainer allows the seal to be used without a groove and limits the compression of the seal to protect against over compression.

Also, the retainer has bolt holes so it can easily be assembled to the fuel nozzle flange. Another C-ring application is MS33 style fasteners. They form the C-ring around a washer creating a boss seal. The washer actually threads onto the fastener, centering the C-Ring and holding it into place. Boss seals can be used for other threaded fasteners as well when there is a match in size.

And again, to summarize some of our C-seal variants, we have the MS33 style boss seals we use with those fasteners, we have the spring energized C-rings along with our C-seals with retainers.

And now I'll turn it back over to Ricki and she'll go into more detail about the retainer C-seals.

Thanks, Jeff. Retainers seals are routinely used in fuel systems and fuel nozzles. The retainer acts as a limiting feature and can be assembled to a flat surface. This erases the need for cavity designing and machining in your hardware. An added benefit is that the retainer is visible after installation to provide assurance of correct assembly. Now we'll move on to air ducts.

The Parker air ducts seal was designed to operate in the exhaust line of engines where some of the most demanding sealing conditions are experienced. Most engines and the exhaust area can reach temperatures upwards of 1300 degrees Fahrenheit and subjected to constant vibrations. These can cause significant problems when trying to maintain a seal. This seal works in application by creating an interference axial fit in the hardware. The curved features allow for the air duct seal to move in the cavity while maintaining contact with the mating flanges.

The Parker seals have been bench tested and field tested to ensure better sealing than competition. You can see some of the data below. Each one of these is custom designed to your application, so please feel free to contact us and we can help start today.

OK, before moving on to seal materials, we're going to launch our second poll question. What are the primary materials used for your high temperature seals? Inconel 718, Waspaloy, Rene 41 or another material. Thank you for your responses.

We will now move on to seal materials Parker offers. In our catalog you'll find a variety of materials that can be used in different cross sections of our metal seals. The most commonly used for gas turbine engines are going to be Rene 41, Waspaloy and Inconel 718. These choices are made primarily based on temperature, but also with consideration of the mating hardware materials.

Parker Metal seals are often plated or coated. We do have bare seals, but in cases where we need to coat or plate seals, this is a critical piece of information.

The surface finish of your mating hardware, no matter how smooth, will have some peaks and valleys. In critical applications, the peaks and valleys will be sealed using a plating or a coating. Because this impression will be taken upon assembly, we do not recommend these seals to be reused.

This is a list of some of our platings that are offered. These are chosen based on the temperature of your application.

Early in the presentation, Jeff mentioned TriCom® coating. This is an anti-wear protection that can be used in place of T800 coatings. T800 is sprayed on, whereas TriCom is electroplated and provides a very smooth surface finish. This is a cobalt chrome carbide and can be used up to 1150 degrees Fahrenheit. Or there's also an H.T. version, which is a cobalt nickel chrome carbide that can be used up to 1400 degrees in continuous exposure. We have documentation and small literature brochures that we would be happy to send you if you have any more questions about this.

Thank you, Ricky, and thank you, everyone, for joining us now.

We'd like to open it up for any questions you might have.