The sinuses are air-filled cavities. 1  They are located: 2  Within the bony structure of the cheeks. 3  Behind the forehead and eyebrows. 4  On either side of the bridge of the nose. 5  Behind the nose directly in front of the brain.
An O-ring is a round ring that is used as a gasket for sealing a connection. O-rings are typically constructed out of polyurethane, silicone, neoprene, nitrile rubber or fluorocarbon. These rings are commonly used in mechanical applications, such as pipe connections, and help to ensure a tight seal between two objects. O-rings are designed to be seated in a groove or housing that keeps the ring in place. Once in its track, the ring is compressed between the two pieces and, in turn, creates a strong seal where they meet.
Steel O-Ring Face Seal Fittings ( ORFS ) O-ring face seal adapter fittings use a straight thread and have a machined groove in the face of the male fitting to accept an O ring (of either Buna N or Viton material). This O-ring is compressed against the flat face of the female fitting for a leak proof connection. ORFS fittings are one of the most recent families of hydraulic adapter fittings and offer excellent leak protection at high pressures. They are compatible with ORFS adapters from most manufacturers including Eaton Aeroquip, Parker, Gates, and Goodyear Hydraulics. Click here to learn more about ORFS fittings.