O-Rings & Custom Sealing Rings

Standard AS568 and metric (ISO 3601) inventory-style supply, Garlast® FFKM for aggressive media, and custom cross-sections when a catalog ring is not quite right—including cover-up style rings for non-standard grooves (oversized cross-section or diameter to “cover” worn or legacy glands—confirm fit with a drawing).

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O-rings are the most versatile and widely used sealing solution across industries. Our portfolio includes standard sizes, metric references, and custom configurations in multiple elastomers—aligned with how buyers actually procure: clear standards, datasheets, and engineering support.

Why Specify Garlast For O-Rings

Standard AS568, ISO 3601 metric, and custom dimensions
Compounds from general-purpose NBR/EPDM through FKM, HNBR, silicone, and Garlast® FFKM
Engineering review of groove, squeeze, and media compatibility on request
Scale from samples and prototypes to production volumes
Links to in-house size charts and material selection tools

[Replace: O-ring assortment, groove diagram, or inspection photo]

Additional Information To Send For the Swiftest Quote

Part definition: Dash number (e.g. AS568-214) or drawing with ID, CS, tolerances, and quantity breaks.
Material: Polymer family, hardness (Shore A), color, and any spec (FDA, USP Class VI, fuel, etc.).
Application envelope: Media, max temperature & pressure, static vs dynamic, and assembly method.
Quality & logistics: CoC, PPAP level, bagging/labeling, and ship-to region.
Don't hesitate to request a quote, our team will assist you with your sealing needs!

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O-Ring Size Charts (AS568 & ISO 3601) Material Selection & Compatibility Datasheets & Documents

Product Types

Standard O-Rings

Standards: AS568, ISO 3601, DIN, JIS

Materials: NBR, EPDM, FKM, Silicone, HNBR, Garlast® FFKM

Applications: Hydraulic systems, pneumatic systems, general sealing

Cover-Up / Retrofit O-Rings

Definition: Non-catalog diameter or CS to fill an existing groove when hardware cannot change—requires drawing sign-off.

Materials: All standard elastomers available

Applications: Legacy equipment, tooling limitations, field service kits

Garlast® FFKM O-Rings

Temperature (indicative): -20°C to +327°C — verify per grade datasheet

Key benefits: Ultra-high purity options, broad chemical resistance

Applications: Semiconductor, pharmaceutical, chemical processing

Custom O-Rings

Capabilities: Non-standard sizes, dual materials, bonded inserts — [TBD]

Tooling: [NRE / no NRE — TBD]

Applications: OEM programs, approvals, long-term agreements

Popular Elastomers

Approximate dry air temperature windows only—final suitability depends on media, pressure, and hardware. Confirm with testing or Garlast engineering.

NBR (Nitrile)

Typical range: approx. -35°C to +120°C (specialty nitriles may extend — [TBD])

Strong general-purpose choice for oils, fuels, and hydraulic fluids at moderate temperature.
Ozone and UV limited—avoid outdoor exposure without protection.

EPDM

Typical range: approx. -50°C to +150°C

Excellent water, steam, brake fluid (DOT), and weather resistance.
Not suited for hydrocarbon oils and fuels.

FKM (Viton®-Type)

Typical range: approx. -26°C to +200°C (compound dependent)

Broad chemical resistance and elevated temperature vs NBR.
Common in fuel systems, chemical process, and high-performance hydraulics.

FFKM (Garlast®)

Published range (grade dependent): -20°C to +327°C — see Material Selection guide

Near-universal chemical resistance for aggressive plasmas, acids, amines, and high temperature.
Specify grade for semiconductor, pharma, or food contact as applicable.

Silicone & HNBR

Silicone typical: approx. -60°C to +200°C static · HNBR: improved heat/oil vs NBR — [TBD specs]

Silicone: low closure force, food/pharma grades available — [TBD].
HNBR: sour gas, refrigerants, and higher temperature oil service — [TBD].

Applications

Hydraulic & Pneumatic Systems

Reliable sealing for cylinders, valves, pumps, and actuators in industrial and mobile equipment.

Automotive Components

Engine seals, transmission systems, fuel systems, and brake components requiring durable sealing solutions.

Industrial Equipment

General-purpose sealing for machinery, processing equipment, and manufacturing systems across multiple industries.

High-Performance Applications

Extreme temperature, chemical resistance, and ultra-pure environments using Garlast® FFKM and specialty compounds.

FAQ

What is the difference between an O-ring and a gasket?

An O-ring is a torus that seals in a precision groove; a gasket is usually a flat or profiled sheet cut to a flange. Both can be elastomeric—the choice depends on hardware and pressure.

What does “cover-up” mean for O-rings?

Informal term for a ring sized to seal a non-standard or worn gland when the housing cannot be remachined. Always validate squeeze, fill, and extrusion gap with a drawing—we do not recommend guessing from calipers alone.

Can you match a competitor compound or color?

Often yes, with a sample or datasheet. Provide the incumbent part number or a small specimen for lab correlation — [policy TBD].

Do temperature tables replace application testing?

No. Published ranges are approximations for screening. Final performance depends on media, pressure cycling, and hardware—as with standard industry disclaimers on distributor material pages.

Related Resources

Size Charts Material Selection Documents Library Contact & RFQ

Information on this page is for general selection only. Garlast makes no warranty that parts will perform satisfactorily in your application until qualified by your tests and approvals. Temperature bands are not substitute for end-use validation. Replace all [TBD] and placeholder fields with approved commercial data before external publication.