Large Diameter O-Rings & Seals
PPE offers the largest fully molded, elastomer O-rings and seals, manufactured on a single tool, in one pressing operation.
Using one of the largest molding machines available, PPE manufactures high quality, fully molded, large diameter O-rings and custom parts for use in compressors, valves, oil & gas equipment, large bore diesel engines, large high pressure vessels, Flat Panel Display (FPD) and semiconductor manufacturing equipment.
PPE’s large diameter, precision molded O-rings and seals are available in sizes up to 2.5 metres (8ft) outer diameter and cross sections from 5mm (0.2″) to 20mm (0.79″).
Benefits of fully molded large O-rings
Below are some of the main benefits of fully molded large O-rings compared with jointed or spliced O-rings. Jointed O-rings are manufactured from extruded elastomer cord that is joined by bonding the two ends together.
Reduced risk of failure
Tighter tolerances
Superior accuracy & consistency
Superior mechanical performance
RGD resistance
Jointed O-rings have inherent weak spots at the joint which can cause premature seal failure.
Fully molded O-rings have no joint that can be a potential point of weakness.
Fully molded large O-rings offer tighter cross-section tolerances to ensure a proper fit in critical equipment compared with jointed O-rings.
Joints can be mismatched causing uneven cross section at the bond, the extruded cord can also have wider tolerances on the cross section.
Spliced O-rings can have mismatched joints caused by misalignment of the bond, or wider tolerances on the cross section of extruded cord.
Fully molded O-rings are manufactured using tooling that is perfectly matched to the required size. This results in accurate part dimensions and batch-to-batch consistency.
Typically, elastomer cord is manufactured at lower pressures which produces a lower density jointed O-ring.
This can adversely effect the compression set resistance and life time performance of the O-ring in service.
Available in high performance explosive decompression resistant elastomer grades, not available as spliced O-rings.
Reduced risk of failure expand_more
Jointed O-rings have inherent weak spots at the joint which can cause premature seal failure.
Fully molded O-rings have no joint that can be a potential point of weakness.
Tighter tolerances expand_more
Fully molded large O-rings offer tighter cross-section tolerances to ensure a proper fit in critical equipment compared with jointed O-rings.
Joints can be mismatched causing uneven cross section at the bond, the extruded cord can also have wider tolerances on the cross section.
Superior accuracy & consistency expand_more
Spliced O-rings can have mismatched joints caused by misalignment of the bond, or wider tolerances on the cross section of extruded cord.
Fully molded O-rings are manufactured using tooling that is perfectly matched to the required size. This results in accurate part dimensions and batch-to-batch consistency.
Superior mechanical performance expand_more
Typically, elastomer cord is manufactured at lower pressures which produces a lower density jointed O-ring.
This can adversely effect the compression set resistance and life time performance of the O-ring in service.
RGD resistance expand_more
Available in high performance explosive decompression resistant elastomer grades, not available as spliced O-rings.
Cleanroom manufacturing of large O-rings
For components that must be manufactured in conditions with low atmospheric contamination, PPE can mold large diameter O-rings and seals in a class 10,000 cleanroom. Our large molding press has been integrated into a custom built cleanroom to provide high quality components using high-purity elastomer materials.

Our molding capabilities include large diameter O-rings and seals manufactured in a class 10,000 cleanroom.
Manufacturing lead-times for large O-rings
PPE understands that critical applications demand the highest level of responsiveness. Large diameter O-rings can be manufactured in the shortest lead-times in the sealing industry for time critical requirements.
High performance materials
With an unrivalled range of elastomer materials available, PPE has an elastomer for every application, with performance characteristics that meet high temperature, high pressure and aggressive chemical requirements.

Perlast®
expand_moreThe ultimate perfluoroelastomers for sealing applications where chemical resistance and high temperature performance are critical.

Perlast® ICE
expand_moreThe ultimate perfluoroelastomers (FFKM) for sealing applications where chemical resistance and extreme low temperature performance are critical.

EnDura®
expand_moreThe ultimate range of elastomers for sealing applications in the world’s most aggressive high pressure environments.
Resources
Below are some of our key resources on large diameter O-rings.
Visit the Resources section to browse our full range of tools and downloads.
Find your nearest sales contact
We're here to create the perfect sealing solution for you…
