SI o-ring  /Rubber o-ring 

part number :R-18-3.5 SI-70A

Material :NBR 

Wire Dia:3.5mm

inner Dia: 18mm

color : white

Hardness :70A

we offer a wide selection of high-quality o-rings for all your sealing needs. Whether you're in need of standard or custom-sized o-rings, we have the perfect solution for you. Our o-rings are made from durable materials and are designed to withstand even the toughest conditions, ensuring a reliable seal every time. We make getting O-Rings easy!

An O-ring, also known as a packing or a toric joint, is a mechanical gasket in the shape of a torus;

it is a loop of elastomer with a round cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, forming a seal at the interface.

The O-ring may be used in static applications or in dynamic applications where there is relative motion between the parts and the O-ring.

Dynamic examples include rotating pump shafts and hydraulic cylinder pistons. Static applications of O-rings may include fluid or gas sealing applications in which:

(1) the O-ring is compressed resulting in zero clearance,

(2) the O-ring material is vulcanized solid such that it is impermeable to the fluid or gas, 

(3) the O-ring material is resistant to degradation by the fluid or gas. The wide range of potential liquids and gases that need to be sealed has necessitated the development of a wide range of materials.

O-rings are one of the most common seals used in machine design because they are inexpensive, easy to make, reliable and have simple mounting requirements. They have been tested to seal up to 5,000 psi (34 MPa) of pressure. The maximum recommended pressure of an O-ring seal depends on the seal hardness, material, cross-sectional diameter, and radial clearance.