The Top 5 Things to Remember When Working with Gaskets for Service Applications

Not all gaskets go into brand new applications straight off the production line. There are many gaskets used across the aftermarket, in service operations and in engine rebuilding. Do the same rules and considerations apply to the seal points and gaskets in service applications as they do in OEM manufacturing?

We have put together a list of considerations for those working with gaskets in situations where a gasket is being replaced.

Things to Remember

1. Flange surfaces will change.

Over time and repeated heat cycles, flange surfaces can warp and become distorted, become pitted or corroded, or otherwise become less than ideal. When replacing a gasket, you’ll either need to spend both time and money machining the flanges back to their original state, or use a gasket that can compensate for the irregularities now present. Often, thicker, more compressible gaskets are used in service applications to not only save cost in flange prep, but to make up for material lost in the flange resurfacing process.

2. Replacement products vary greatly.

Service parts are available across an entire spectrum of price and quality. Customers typically are in control of choosing the cost and quality of the parts used in the repair. Parts are available from OEM quality (or better) down to low cost/low quality choices. How long do you want the gasket to last?

3. There are alternatives to the OEM gasket.

While marketing experts will want you to believe that you can only replace a gasket with the same OEM gasket, there are actually quite a few OEM-quality replacements on the market. You can usually save some money and sometimes get better performance.

4. Multiple factors to consider

There are many factors to consider in the process of replacing gaskets. One of which is the installation process itself. What is the torque? What is the sequence? What is the process? Should I include a sealant? Should I retorque it? Is it possible it might be upside down? Are the flanges clean and prepped? The answers to these questions will ultimately help you to settle on the proper replacement gasket, as well as ensure it will perform as expected in your application.

5. Materials / Construction

Have you explored and considered the various material choices for service applications? Which one is best? There are often different constructions of gaskets. Some are single layer materials, some are embossed metal, some are composite laminates. Which is best? Often, the composite designs are the best choice in replacement parts as they best compensate for the factors mentioned throughout this post.

Plenty of Options

Although there are a few extra considerations when choosing a gasket or gasket material for a service application, you may actually find that you have a little more latitude. There are materials out there that have characteristics that excel in these markets. Talk to your trusted gasket material supplier to  figure out which materials will be best suited for your application.

What differences do you find between sealing OEM and service applications?

Metal Tech offers the HT337, which works well in many service applications.Hi-Tex Product Comparison

3 Reasons Why You May Want to Utilize an Insulating Gasket

Sometimes a gasket needs to be more than just a gasket. There are times you may find that you are in need of an insulating gasket. There are also times that you could use an insulating gasket and don’t even realize it. If you’re not quite sure what you need, continue reading to learn about a few instances when an insulating gasket may be a benefit to your application.

Before we jump into a few examples, we thought we’d start with a short explanation on insulating gaskets in general. First, it isn’t a new gasket technology. Gaskets with insulative properties have been on the market for years. However, due to the increased heat in applications, the benefits of these materials are now in demand as engineers are constantly working to manage the heat.

So what are these materials? Metal reinforced composite laminates are your best choice when it comes to high temperature gaskets that also require insulative properties. Insulative materials by themselves can be fragile, the metal core gives them strength.

Reasons to Utilize an Insulating Gasket

1. There isn’t room for a heat shield.

Engines are getting both hotter and smaller, which is not a good combination if there are sensitive components that need protection. Designing a heat shield small enough to fit into some of these areas can be a difficult task. If there is a way to utilize the insulating properties of your gasket to reduce the heat flow, you may have solved your space issue.

2. Save money and simplify your design.

We don’t know any engineers that want to add cost and complexity to any design, so if there is a way to minimize both of these with simply a gasket, why wouldn’t you at least check it out?

3. You suspect heat soak is present.

All systems may be humming along while the application is running. However, what happens when it is turned off? Heat soak is a common issue when there are no cooling systems protecting sensitive components. An insulative gasket does its job whether or not the application is running. An example of this might be EGR valves, where actuators are better if they don’t get as hot as the valve itself. Heat soak can be an enemy here.

Selecting a Material

As with any application, you need to ensure that any gasket material chosen is suitable for the conditions that it will see. The best insulative materials are going to be metal reinforced composites that contain vermiculite, mica or fiber materials. Finding which one seals and insulates best in your application is something that will need to be tested. As you explore this idea, talk to your trusted gasket material supplier to narrow down your choices.

Have you used an insulating gasket before?Hi-Tex Product Comparison

6 Ways to Ensure You Have a Tight Seal in Your Gasketed Joint

The lack of a tight seal in a gasketed joint is a ticking time bomb. The timing of the issue presenting itself may vary, but unfortunately, you will have issues. The good news (for those of you that love troubleshooting) is that there are a variety of things that can contribute to the problem. In a perfect world, all of these things would be addressed during the design phase. Hopefully we can help some of you start to recognize these things sooner rather than later to get you out of the troubleshooting group!

We put together a short list of things that you should consider when it comes time to design or troubleshoot your gasketed joint.

Ways to Ensure a Tight Seal

1. Is the proper load applied?

Bolts not tightened to the proper torque values spell trouble for your application. If the load values defined in the development stages are not adhered to, you will most likely find a leaking gasket (and possibly further damage if it goes on for too long). What if you don’t know what the load should be? Start with the specified gasket material. You may be able to reverse engineer the values based on the recommended loads that the gasket material is designed for (you may need to talk with the materials supplier). You might also gather input from service instructions for similar applications. It will take some trial and error, but you can probably figure it out.

2. Can the gasket withstand the conditions it is under?

Sometimes conditions in the application are underestimated, and sometimes the robustness of a certain gasket material is overestimated. Whichever way it happens to go, there will most likely be problems. Is your gasket material designed to resist the effects of the fluid, pressure, and temperature of the joint? If it isn’t, you can count on having trouble maintaining a tight seal. However, this is generally an easy fix if you do a little research into materials that can withstand the specific conditions in your application and choose properly.

3. Is the bolt design sufficient?

This is probably the most expensive problem on this list. A redesign due to an incorrect bolt design can cost a lot of money, especially if you are too far down the design path. If your answer to this question is “no”, and you do have an insufficient bolt design, we can offer some advice on where to go from here. If there is any hopeful news in this scenario, it is that there are materials out there that are more forgiving than others that can help mask questionable design choices. Talk to your trusted gasket material supplier about some of the composite materials on the market. Three layer composites (or metal reinforced materials) can be manufactured to a specific thickness and they conform very well to flange surfaces – both of which can help compensate for bolt design issues. It isn’t always a magic bullet, but it’ll do the job in a lot of situations where nothing else will work.

4. Are the flanges appropriate for the gasket technology chosen?

Flange surface finish plays a huge role in the ability for certain gasket materials to adequately hold a tight seal. Gaskets made of stainless steel (MLS/SLS) require mirror-smooth surfaces, while metal reinforced graphite and certain fiber gaskets are more forgiving. If the flanges are not machined properly, or they wear over time, you will start to have sealing issues with MLS/SLS.

5. Are the leakage requirements met?

It is a common misconception that a gasket is expected to never leak. Leakage requirements are set during the design phase (you’ll commonly see mL/minute or mL/hour) and the load on the joint has a direct effect on whether or not these numbers are achieved. If you are exceeding your leakage requirements, that is a clear indication that your seal is not as tight as it needs to be.

6. Is a re-torque necessary?

What if you’re feeling pretty confident in everything above, and you’re still having issues with maintaining a tight seal? Maybe the solution is something as simple as a re-torque. If you have gaskets installed that are going through their first heat cycles, bolts loosen and a re-torque is often necessary. Without it, the tight seal you thought you had prior to running your application is long gone.

Maintaining the Seal

As you can see, there are definitely some things to consider if you are having trouble maintaining a tight seal. Some are always quick to blame the gasket, but a gasket is only as good as the conditions that it is designed for and the type of conditions it is placed under. It is important to have a full understanding of all of the things that can lead to the demise of a tight seal.

What is the most common issue you find with your seals remaining tight?Armor product comparison

What Is A Metal Reinforced Gasket and Why Do I Need One?

If you were in the market for a gasket, do you even know where to start? If not, check out some of our previous posts The Most Commonly Used Gasket Materials & Why You Need Them All and Why Would I Use Composite Gasket Material When I Can Use MLS? As you can see, we’ve broken down why you want to consider a composite material. Now, the big question for some of our readers may be: “What exactly is a composite gasket”?

Breaking It Down

For starters, the terms ‘metal reinforced gasket’ and ‘composite gasket’ are synonyms. The most common types of composite gaskets consist of a facing material chemically or mechanically bonded to a piece of metal (think of an oreo). Some applications actually use a one-sided configuration, but we’ll save that for another day. The possibilities are virtually endless if you start to think about what facings you could combine with the metals. However, feasibility and practicality tend to narrow your gasket material options when it comes to the application. Even so, you are in control of the materials and the thickness to specifically meet your needs.

Some of the more popular facings are: graphites, fiber blends, graphite/fiber blends, vermiculite, mica, beater-addition fiber sheet, compressed sheet material, just to name a few.

The facings are most often bonded to steel. This produces the most cost-effective, strongest, and durable solution. Other core options are: stainless steels, aluminum alloys, expanded metals, wire mesh, thin foils, among others.

Your application will lead you to specific facings and metals depending on what your requirements are. Whether you are looking for a material for a new application, or looking to replace a material that isn’t working for your current application, a good gasket material supplier will be able to walk you through the process of selecting what you need. There’s no need to try to figure it out on your own!

Ok, So Why Do I Need One?

Now that we’ve been through what exactly a metal reinforced gasket is, let’s talk about why you need one.

1. It is stronger than a “homogeneous” gasket material, to resist blowout and retain the internal pressure of the joint.

2. It is dimensionally stable; will not shrink or grow like some products.

3. It has stiffness for better handling and assembly.

4. It has resistance to crushing or splitting.

5. It has no potential for center leak path with solid core items.

So Now What?

Depending on the reason that you landed on this blog, you may be ready to find some composite material to test in your application, or maybe this is just information you are going to tuck away for a future application. Whatever the reason, hopefully this helped to educate (or reeducate) you on metal reinforced gasket material.

What other questions do you have about metal reinforced materials?

Request a Call