Hollow O-Rings | O-Ring Cord
Hollow O-rings are an alternative to standard O-rings, when low closing force is required. The reduced closing force is achieved by replacing the solid cross-section by a hollow cross-section, without reducing the material hardness. Hollow O-rings are used for instance for sealing lids and doors.
- Low pressure static applications.
- Applications where low closing force is required.
- Applications with rough surface finish.
Not suitable for
- High pressure applications.
- Dynamic applications.
- Low closing force
- Easy to make large sizes I.D. < 1000 mm
How do Hollow O-Rings work?
Hollow O-rings work the same as regular O-rings. An O-ring is an elastic part placed between two parts and then squeezed to fill up the gap between the two parts. When placed under pressure, the ring is forced to “flow” within the groove toward the clearance gap. As the ring flows against the gap, it produces zero clearance and prevents the sealed substance from escaping. The difference between a regular O-ring and a Hollow ring is the fact that the hollow core makes it much more easy to compress the ring
Any size available upon request.
NBR: -40° to +108° C
EPDM: -55° to +155° C
FKM: -25° to +204° C
NBR, EPDM, FKM, CR, FVMQ, HNBR, FFKM, PU, VMQ
KTW, USP, NSF 51 61, WRC, WRAS, FDA, R67 01
AS 568A, DIN 3701, BS 1806/ BS 4518, JIS B2401, JIS NFT47-501, SMS 1568 en ISO 3601.
Hollow O-Ring Types
Type Nitrile (NBR)
NBR hollow O-rings can be used in static applications where low closing force is required. Nitrile has a good general oil/fuel resistance, but poor ozone and weathering resistance.
Type Silicone (VMQ)
Silicone hollow O-rings can be used in static applications where low closing force is required. VMQ has a good heat resistance up to 232°C in hot air and up to 100°C in water. It offers excellent resistance to ozone and weathering.
Alternatives for square rings
X-rings, or Quad rings®, are an alternative for D‐rings. X-rings have four lips and therefore they have at least four sealing surfaces. The benefits are: high stability, space for lubricants between the sealing lips