Sealing profiles include seals, gaskets and edge protectors. All of these protect the edges of doors, windows and machinery from damage while preventing the ingress of dust, debris and moisture. Depending on the material, they can also dampen vibration and noise. In this guide, we’ll explain what you need to know about these critical components, including:
The two terms are often used interchangeably but technically, they are different. They are both sealing profiles and essentially serve the same function. The difference lies in their applications.
For example, a rubber seal strip is used for moving components. Pumps, bearings and rotating shafts are good examples that require a seal profile. Seals are typically round and relatively flat. Shown here are o-rings , which fall into this category. These particular seals are used for hydraulic and pneumatic applications.
Gaskets, on the other hand, are used in static environments to fill the space between flat surfaces. Shown here is a 3D CAD image of a glazing gasket, also called a window seal or window gasket. Gaskets are typically cut into the shape needed to fit the components they’re being affixed to.
Here are some examples of different types of sealing profiles, along with their uses.
Gaskets can be trickier to choose than seals due to their shapes. You’ll need to take into consideration these factors:
Used for: Control panels and windows on generators and other machinery; automotive interiors and underside of car
Used for: Window seals for inspection panels where glass or acrylic panels are not subject to high pressure or exposure to weather elements
Some gaskets and seals contain steel spring cores. These are used when you need a reliable seal in critical applications that operate in typically extreme conditions. A high-temperature application is a good example of when you should choose a gasket with a steel spring core.
Using the right material is critical to the sealing profile’s performance. Each has their own advantage. That said, the same material is not always the same. For example, EPDM produced by one manufacturer could offer better chemical resistance than an EPDM gasket made by another. Always read the manufacturer’s material sheet carefully.
Still, we can talk about materials in general terms as a starting point. The most popular materials for seal profiles are:
Ethylene propylene diene monomers, or EPDM, is a synthetic rubber. More specifically, it’s an elastomer, meaning that it has elastic properties. It’s often referred to as ‘EPDM rubber’ due to its similarities to rubber. This makes it ideal for gaskets and seals. Along with its flexibility, it also resists heat and chemicals. You can learn more about this material in our guide, EPDM vs silicone: what’s the difference?
Popular sealing profiles in: Automotive, machinery, generators and HVACs, medical devices, electronics, double-glazing window seal and construction.
Generally, rubber is compatible with acids and alkalis, but some rubber seals and gaskets do not stand up well to petroleum fluids. Still other rubber profiles are excellent at standing up to high temperatures. All that said, rubber is excellent as a seal to prevent leaks.
Popular sealing profiles in: Automotive, industrial machinery pumps and valves, and medical-device seals
Common foam materials include polyethylene, polyurethane, neoprene, nitrile and PVC. Two layers of the material are bonded by adhesive tape. These types of gaskets usually cost more than others, but for damping vibration, reducing noise and providing insulation, you can’t do much better.
Popular sealing profiles in: Electronics, enclosures and construction
Polyvinyl chloride, known as PVC, is available as either rigid or flexible. Obviously for sealing profiles, it’s all about flexibility. Sealing profiles made with PVC resist UV, so they’re especially good for outdoor applications. PVC also absorbs shock and reduces noise.
Popular sealing profiles in: UPVC window seals, glazing seals