Plastic Half-Round Bulb Seals

Plastic half-round bulb seals for doors and windows have a halfmoon bulb that compresses to fill and seal the gap. These glazing seals also have a mounting mechanism that pushes into place or attaches with adhesive tape. Half-round bulb seals can be co-extruded in different materials, or with the same material in different durometers. They can also have a single substrate that uses the same material and durometer.

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Half-Round Bulb Seals

Vip Rubber and Plastic of La Habra, California (USA) makes half-round bulb seals for manufacturers of commercial and storefront doors and windows. We do not keep these items in stock for low-volume consumer sales. Minimum order quantities apply. Lead times may vary. If you are manufacturer who needs storefront gaskets or window seals, we invite you to contact us to discuss your application.

Santoprene Half-Round Bulb Seals vs. PVC Half-Round Bulb Seals

Santoprene is used in half-round bulb seals because of its excellent compression set and other desirable properties. For example, this thermoplastic elastomer (TPE) provides environmental resistance that’s comparable to EPDM, a rubber that is used in many outdoor sealing applications.

Flexible polyvinyl chloride (PVC), or Flex PVC, can be used for half-round bulb seals instead, but is susceptible to over compression. If a gasket fails to bounce back when compressive forces are removed, such as when a door or window is opened, the resulting gap that is created can admit wind, water, and weather.

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Selecting Half-Round Bulb Seals for Commercial Doors and Windows

Custom plastic half-round bulb seals are available in many different styles and sizes, and the bulb location can vary. Depending on how your door or window opens, you may need a bulb that’s atop the mounting mechanism. You can also choose a glazing seal where the bulb is on the bottom.

Because jam dimensions vary, it’s important to find the average and to use this measurement when you select a product. To account for bulb compression, add between 25% and 50% to the average jam dimension. Vip can help you with product selection and also offers other types of plastic extrusion profiles.

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