What is the Benefit of a Gasket with a Screen Core?

Metal-reinforced gaskets are a staple in the industry. They provide radial strength for both handling and in-application uses. The gaskets are dimensionally stable and very robust.

But some gaskets have screen cores…is this a good thing? In most cases, no. Read on to learn why.

Screen Core Materials

Screen core is one version of a metal center layer sandwiched between two layers of sealing material. It provides a metal core layer for a laminate that offers strength while allowing a place for an adhesive bond to occur. It also provides an additional level of lateral strength as the facing cannot slide laterally on the screen core. While it seems like it might be a good idea, the drawback comes with the issue of sealability. By its nature, screen is a woven material, generally wire, in an over/under overlapping pattern. This is what creates the problem. The over/under configuration provides a leak path for the fluid being sealed. The facing material must conform tightly to the metal or a leak will generate. This is difficult for the facing to do as there is an inherent void to be dealt with. In some cases, this can be addressed by a heavy layer of adhesive, but this is not the best solution since it only puts a band-aid on the problem.

If Not Screen Core, Then What?

A better solution is a solid core laminate using flat metal and a thermally-cured adhesive. This product provides NO leakpath along the core due to the adhesive bond. Another core style is expanded steel. While it is a “porous” core, it also has NO direct leak path through the core by the nature of its design, thus allowing the adhesive to bond the two sides of facing directly through the core.

As with all products that contain a thermally-cured adhesive, you need to pay attention to the operating temperatures of your application and the specification of your chosen material. In fluid sealing applications, temperature capability of solid core materials is often more than sufficient to withstand the conditions of the application.

Find A Solution

As you can see, there are some things to be aware of if you’re thinking about using a screen core as a layer of metal-reinforcement. For fluid sealing applications, there are better choices available, such as solid core laminates or expanded core laminates.

If you aren’t familiar with solid core laminates, talk with your trusted gasket material supplier to learn about your options.

What type of material do you prefer in this situation?Surbond product comparison

Metal Tech offers solid core products under the SURBOND product group for fluid sealing applications.

Tang (It’s Not Just For Astronauts)

When you hear the word “tang” what conjures up in your mind…an orange-flavored drink, a fish, a style of gasket material, or other definitions? The list goes on. We’ll let you guess which one we’re here to talk to you about. Is anyone thirsty for some Tang? If not, let’s start our discussion.

When we talk about our tanged (or perforated) core materials, do you have an understanding about what that is and why you may need it? Gasket material that is mechanically bonded together provides both strength and durability for the gasket in your application. There are also other reasons why you’d want to use a tanged core material – keep on reading to see why.

What is the Value to a Tanged Core?

1. Mechanical bond

With tanged core, there is a mechanical bond holding the material together, so as not to depend on a chemical bond that may degrade with heat exposure. Exhaust gasket composition benefits greatly from this mechanical bond to ensure the material retains its integrity both at and beyond the intended operating conditions.

2. Handling strength (durability)

The tang core provides strength for handling, often bonding high temp materials that would be weak if unsupported, creating a robust material with the metal-reinforcement. Handling in installation is a huge benefit.

3. Radial strength

The other strength issue is radial strength. This provides blowout resistance. The tang core provides a physical barrier and containment mechanism to hold the facing in place over the life of the joint. As compared to a glued laminate, the facing cannot extrude away from the core.

4. Durability

In addition to handling strength in assembly, the tang core also provides durability in the application. It serves to contain the seal’s facing in place to resist expansion and contraction due to thermal growth of the flanges.

5. Flange loading

Tanged core helps to provide load retention (torque retention of the fasteners). It does this by offering the metal structure providing “pushback” against the flange. The tangs create a “load stop” and structure, shouldering the load and preventing the facing from crushing under high load spots.

Give It a Shot

As you can see, it is hard to go wrong with a tanged core gasket material. Combined with the appropriate facings, this is a core that can meet the requirements of high temperature and high pressure applications. If you’ve never used tanged core materials before, you should consider how they would work in your application. A trusted gasket material supplier can help you decide if it is something you should explore.

Ok, now we’re thirsty.Request a Call