O-rings are simple by design — defined by just two dimensions: inside diameter and cross-section.
But long-term performance depends on far more than size. Material selection, temperature exposure, pressure cycling, media compatibility, and system design all determine whether a seal performs — or fails.
At Performance Seals, we help engineers evaluate application conditions — not just part numbers.
The O-ring may be one of the simplest components in a system — but when selected correctly, it becomes one of the most reliable. Watch our 60-second breakdown of why proper material and application matching matters.
An O-ring is a torus-shaped mechanical seal designed to prevent the passage of fluids or gases between two mating surfaces. When compressed within a gland, the elastomer deforms to create a barrier that blocks leakage under pressure.
O-rings are used in:
Their simplicity allows for high reliability — provided the correct material and size are selected.
For detailed engineering data, groove design recommendations, sizing charts, and material compatibility information, reference the Parker O-Ring Handbook (ORD 5700).
The handbook includes:
We supply O-rings in a wide range of elastomer classes, including Parker-engineered compounds for demanding applications.
Common Material Classes
We also provide:
O-rings are manufactured to globally recognized standards.
AS568 (Inch Series)
Metric Sizes
Japanese (JIS) & British (BS) Standards
Used in global applications and legacy equipment.
O-ring cord is a general purpose, continuous extruded elastomer material supplied in bulk lengths with a round cross-section. Unlike molded O-rings, cord is not pre-formed into a loop. It can be cut to length and joined to create custom diameter seals. Cord stock allows flexibility without tooling costs.
Available in common elastomer classes including:
Vulcanization (also called splicing) is the process of chemically bonding the cut ends of O-ring cord together using heat and pressure to form a continuous loop.
The splice restores elasticity and strength at the joint, creating a functional custom O-ring.
O-ring cord is ideal when:
✔ A custom inside diameter is required
✔ The seal diameter is too large for molded production
✔ No tooling budget is available
✔ A rush replacement is needed
✔ Field assembly is required
✔ Low volume custom sizes are needed
Molded O-rings are typically preferred when:
A vulcanized splice is strong — but it is not identical to a fully molded O-ring.
Molded O-Ring
Best for production, high-performance, and critical sealing applications.
Cord + Vulcanization
Best for large diameters, custom sizes, and quick-turn general purpose solutions.
At Performance Seals, we provide: