AS568-357 FFKM O-Ring — 139.07 × 5.33 mm
A thick, durable section engineered for large-diameter static seals and high-tolerance groove applications. With an inside diameter of 139.07 mm and a 5.33 mm cross section, this is a large-bore seal for large-bore machinery and process equipment. Moulded from Aperflu 2275 perfluoroelastomer (FFKM) for continuous service up to 200 °C, this seal resists hot acids, caustics, solvents, fuels and steam.
Dimensions
| Dash number | AS568-357 |
|---|---|
| Inside diameter (ID) | 139.07 mm (5.475 in) |
| Cross section (CS) | 5.33 mm (0.21 in) |
| Outside diameter (OD) | 149.73 mm (5.895 in) |
| Material | Aperflu 2275 perfluoroelastomer (FFKM) |
| Service temperature | up to 200 °C continuous |
Paint, coatings and solvent dispensing
Dispensers, sprayers and quick-connect couplings continuously wetted by solvents and pigments. This FFKM keeps dimensional stability and seal force where solvent resistance is the deciding factor, outlasting FKM in continuous solvent exposure.
Why Aperflu 2275 FFKM
Perfluoroelastomer (FFKM) is the most chemically and thermally resistant elastomer class available — rated for continuous use beyond 200 °C and stable against well over 1,600 chemicals, which is why it is specified where FKM, silicone and EPDM fail.
Typical applications
Large flanges, vessel and tank closures, heavy machinery and static joints, where Aperflu 2275 outperforms FKM and EPDM in aggressive media and elevated temperature.
Compound properties
| Property | Typical value | Test method |
|---|---|---|
| Hardness | 70 – 71 Shore A | GB/T 39693.4 |
| Tensile strength | 21.2 – 21.8 MPa | GB/T 528 (dumbbell type 2) |
| Elongation at break | 155 – 170 % | GB/T 528 (dumbbell type 2) |
| Compression set, 200 °C × 70 h (25 %, method B) | 15 – 16 % | GB/T 7759.1 |
All values are typical. Every batch is shipped with an individual certificate of analysis and may differ from the typical values listed here.
Chemical resistance
The fully fluorinated backbone of Aperflu 2275 resists the aggressive media that attack FKM, EPDM and silicone — including concentrated hydrochloric, nitric, sulfuric and glacial acetic acids, strong caustics, and a broad range of solvents and fuels. Refer to the rating table below for guidance, and confirm your exact media with our engineers.
| Media group | Rating |
|---|---|
| Hydrochloric acid | Excellent |
| Nitric acid | Excellent |
| Sulfuric acid | Excellent |
| Acetic acid (glacial) | Excellent |
| Other hot organic & inorganic acids | Excellent |
| Caustics (ammonia, NaOH up to 50 %) | Excellent |
| Ketones, aldehydes, esters, ethers, alcohols | Excellent |
| Solvents, fuels, hydrocarbons, sour gases | Excellent |
| Steam and hot water | Excellent |
| Ethylene diamine & high-temp amines | Good – contact us for grade selection |
| Clean-in-place (CIP) / steam-in-place (SIP) agents | Excellent |
| Active pharmaceutical ingredients (APIs) | Excellent |
Ratings are typical for peroxide-cured FFKM compounds at room and elevated temperature. Final suitability depends on concentration, temperature and pressure — contact us for a compound recommendation against your specific media.
More AS568 5.33 mm cross-section sizes
Need AS568-357 in a custom colour or quantity?
Tell us your dash number, quantity and service media. We quote within 24 hours.
Request a Quote