OSN’s o-ring cord range is designed to provide a fast, versatile and economical solution when standard o-rings are not available or when special sizes are required. It is an elastomeric cord of circular cross-section supplied on reels or by the metre, which can be cut to the length needed and joined by bonding or vulcanisation to make custom seals of any diameter. Thanks to its excellent finish, dimensional calibration and the wide variety of compounds available, o-ring cord is a reliable alternative for static sealing, large flanges, industrial covers, on-site repairs and special equipment.
OSN supplies o-ring cord in the elastomers most widely used by industry, to suit different fluids, temperatures and working conditions.
Standard: NBR, FKM, EPDM, VMQ, CR.
Technical: HNBR, FVMQ, FEPM (AFLAS®), FFKM, PU, ACM, AEM, ECO.
Food grade: NBR, EPDM, VMQ, FKM and FFKM with FDA and/or EC 1935/2004.
Detectable: metal/X-ray detectable NBR, EPDM and VMQ.
Cellular: sponge NBR, EPDM, VMQ, CR and FKM.
NBR is the most widely used option for oils, mineral greases and hydraulic installations, thanks to its excellent balance of mechanical performance and cost. FKM stands out for its high chemical and thermal resistance, making it particularly suitable for fuels, aggressive hydrocarbons and high-temperature applications. EPDM offers strong resistance to hot water, steam, ozone and weathering, making it an ideal solution for hydraulic, chemical and outdoor installations. VMQ silicone provides a wide temperature range and excellent ageing stability, which is why it is widely used in food, sanitary and electrical equipment. Other compounds such as CR, HNBR, polyurethane and special materials are also available on request for demanding applications.
We supply o-ring cord in compounds suitable for contact with food, drink and pharmaceutical products. Materials compliant with FDA and European Regulation (EC) 1935/2004 are available, including NBR, EPDM, VMQ (silicone), FKM and FFKM. We also supply metal- and X-ray-detectable versions and platinum-cured silicone compounds for applications with the highest hygiene requirements.
To suit the needs of each application and manufacturing process, OSN can supply o-ring cord in different formats. We offer cut lengths from one metre, ideal for maintenance, repairs or one-off seal manufacture. We also supply full reels, available depending on material and cross-section on cardboard or plastic spools to make storage and handling easier. O-ring cord can also be supplied in coils or rings, which optimises transport and allows convenient use in workshops and on production lines alike. This flexibility reduces waste, optimises costs and ensures the exact quantity needed for each project is always available.
It should be noted that, because of the nature of the extrusion process, o-ring cord tolerances are usually wider than those of o-rings moulded to ISO 3601. For this reason, o-ring cord is particularly suited to manufacturing large-diameter seals, special solutions and static applications where some dimensional flexibility is acceptable, whereas moulded seals remain the preferred option when tighter tolerances and greater geometric precision are required.
For detailed information on sizes, configurations, performance and available references, please consult the technical catalogue.
O-ring cord tolerances vary according to the nominal diameter or cross-section of the cord and the material selected.
| Thickness / nominal cross-section d2 (mm) | NBR | FKM | VMQ / Silicone | EPDM |
|---|---|---|---|---|
| 1 | ±0.20 | ±0.20 | ±0.30 | ±0.30 |
| 1.5 | ±0.20 | ±0.20 | ±0.30 | ±0.30 |
| 1.6 | ±0.20 | ±0.20 | ±0.30 | ±0.30 |
| 1.78 | ±0.20 | ±0.20 | ±0.30 | ±0.30 |
| 2 | ±0.20 | ±0.20 | ±0.30 | ±0.30 |
| 2.4 | ±0.20 | ±0.20 | ±0.30 | ±0.30 |
| 2.5 | ±0.20 | ±0.20 | ±0.30 | ±0.30 |
| 2.62 | ±0.20 | ±0.20 | ±0.30 | ±0.30 |
| 3 | ±0.25 | ±0.25 | ±0.35 | ±0.35 |
| 3.53 | ±0.35 | ±0.35 | ±0.35 | ±0.35 |
| 4 | ±0.35 | ±0.35 | ±0.35 | ±0.35 |
| 4.5 | ±0.35 | ±0.35 | ±0.35 | ±0.35 |
| 5 | ±0.35 | ±0.35 | ±0.40 | ±0.40 |
| 5.33 | ±0.35 | ±0.35 | ±0.40 | ±0.40 |
| 5.5 | ±0.35 | ±0.35 | ±0.40 | ±0.40 |
| 5.7 | ±0.35 | ±0.35 | ±0.40 | ±0.40 |
| 6 | ±0.35 | ±0.35 | ±0.45 | ±0.45 |
| 6.35 | ±0.40 | ±0.40 | ±0.45 | ±0.45 |
| 6.5 | ±0.40 | ±0.40 | ±0.45 | ±0.45 |
| 6.99 | ±0.40 | ±0.40 | ±0.50 | ±0.50 |
| 7.5 | ±0.40 | ±0.40 | ±0.50 | ±0.50 |
| 8 | ±0.40 | ±0.40 | ±0.50 | ±0.50 |
| 8.4 | ±0.40 | ±0.40 | ±0.50 | ±0.50 |
| 8.5 | ±0.40 | ±0.40 | ±0.50 | ±0.50 |
| 9 | ±0.40 | ±0.40 | ±0.50 | ±0.50 |
| 9.5 | ±0.40 | ±0.40 | ±0.50 | ±0.50 |
| 10 | ±0.40 | ±0.40 | ±0.50 | ±0.50 |
| 11 | ±0.50 | ±0.50 | ±0.70 | ±0.70 |
| 12 | ±0.50 | ±0.50 | ±0.70 | ±0.70 |
| 13 | ±0.50 | ±0.50 | ±0.70 | ±0.70 |
| 14 | ±0.50 | ±0.50 | ±0.70 | ±0.70 |
| 15 | ±0.50 | ±0.50 | ±0.70 | ±0.70 |
| 16 | ±0.50 | ±0.50 | ±0.70 | ±0.70 |
| 18 | ±0.70 | ±0.70 | ±0.90 | ±0.90 |
| 20 | ±0.70 | ±0.70 | ±0.90 | ±0.90 |
| 21 | ±0.70 | ±0.70 | ±1.00 | ±0.70 |
| 22 | ±0.70 | ±0.70 | ±1.00 | ±0.70 |
| 23 | ±0.70 | ±0.70 | ±1.00 | ±0.70 |
| 24 | ±0.70 | ±0.70 | ±1.00 | ±0.70 |
| 25 | ±0.70 | ±0.70 | ±1.00 | ±0.70 |
| 26 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 27 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 28 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 29 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 30 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 31 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 32 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 33 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 34 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 35 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 36 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 37 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 38 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 39 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 40 | ±0.80 | ±0.80 | ±1.30 | ±0.80 |
| 41 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 42 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 43 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 44 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 45 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 46 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 47 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 48 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 49 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 50 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 51 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 52 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 53 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 54 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 55 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 56 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 57 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 58 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 59 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 60 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 61 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 62 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
| 63 | ±1.00 | ±1.00 | ±1.60 | ±1.00 |
If you need to manufacture an o-ring in a special size, select the most suitable material for your fluid or check the availability of a particular cross-section, OSN’s technical team is at your disposal. Contact us and we will advise you on the compound, hardness, profile and dimensions best suited to guaranteeing maximum reliability and service life for your sealing system.
