The Advantages of Custom Seals

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Why You Should Use Custom Seals

While you could buy seals made with the size and materials of industry standards, its performance simply won’t hold up. Whether you have a static or a dynamic application, each one has its own unique needs and circumstances. Wouldn’t you rather create the perfect solution to your problem, rather than finding a product that only approximately fills the needs of your application?

That’s why you should have your seals custom built: you’ll be able to go through each step of the production with your application in mind.

Size

No matter how big or large your application, Real Seal has the solution. We can produce parts anywhere between 0.50” to 27” in diameter. Our state-of-the-art machinery will produce parts with the exact dimensions you need.

Manufacturing Processes

Each manufacturing process has its own advantages and disadvantages, depending on the needs of the application. Real Seal’s manufacturing process balances injection molding and compression or transfer molding.

By combining the three manufacturing processes above, Real Seal can produce just about any seal for any application:

  • Injection molding is considered the most cost-effective molding process, suitable for high-volume productions of small products that require tight tolerances and little finishing. The process involves feeding material into a press, which is warmed and injected into a mold. The process is extremely precise, since the pressure temperature and speed at which the material enters the mold can all be controlled. This cost-effective process can produce parts quickly.
  • Compression molding is best suited for low-to-medium production volumes and larger parts which do not require the tightest tolerances or perfect finishes. The rubber is pre-heated, and then inserted into a mold by a press where it is held until it is cured. It produces more intricate products with fewer knit lines. Other benefits include: fast production, low tooling costs, and the ability to produce high durometer materials.
  • Transfer molding uses a press and mold much like compression molding. But unlike compression molding, transfer molding uses a piston to force a material through a passage into the mold cavity. This method can produce very complex components with tight tolerances at a high production rate. It can also handle larger products. Unfortunately, these benefits come with a much higher production cost.

Material

One of the most important choices you will make for your seal is the material it is made of. There are a wide variety of materials to choose from, each with their own unique properties. If you haven’t determined the right material for your application, the performance of your application and the seals themselves have likely been suffering as a result. In some applications, the performance of the seal material can make or break the entire system.

Some of the materials you will have to choose from include the following:

  • Nitrile is the most widely used elastomer in the seal industry due to its ability to resist petroleum products and is compounded for use in temperatures ranging from -22°F to 212°F. Since it is a copolymer consisting of butadiene and acrylonitrile, they can be added in different proportions in order to give the product the properties needed for the application. For example, it may result in improved performance within a specified temperature range.
  • Ethylene-propylene compounds are typically combined with a third monomer to produce EPDM. They are often found as seals in brake systems, as well as applications with hot water or steam. It is resistant to mild acids, detergents, alkalis, silicone oils and greases, ketones, and alcohols. They do not perform well with petroleum oils, mineral oil, di-ester lubricants or fuel.

Other common materials include:

  • Hydrogenated Nitrile (HNBR)
  • Fluorocarbon (FKM)
  • Neoprene/Chloroprene (CR)
  • Polyacrylate (ACM)
  • Polyurethane (AU) (EU)

Helping You Produce the Seals You Need

There are so many different factors to consider in seal production, and just one misstep with any of them can negatively impact the performance and longevity of your seal. That’s why Real Seal has its own full-time chemist and support staff to analyze your situation, and produce a seal that meets your needs. With our experience producing thousands of seals, you can be sure that you’ll have a seal that performs to your standards. Give us a call to get started today.