O-Ring Cords

O-rings are commonly used between two parts to create a seal, preventing gas or liquid from escaping. The O-ring is placed within a groove to keep it in place and then compressed by the parts on either side to ensure a flush seal.

An O-ring cord is a versatile and cost-effective alternative to standard O-rings, especially when a suitable size is unavailable or too costly. It's essentially a length of rubber cord with a circular profile that can be custom-cut to the required length, allowing you to create a perfectly sized seal on demand.

How do O-Ring Cords work?

The process of creating a custom seal with an O-ring cord is straightforward and effective. First, the rubber cord is cut to the precise length needed to fit the groove, and its ends are joined with a specialised adhesive to form a strong, seamless ring. Once formed, the ring is placed into its designated groove.

As the two components of the machinery are compressed together, the rubber cord seal flattens, filling the entire cross-section of the groove to create a complete and reliable static seal. This method provides a quick, on-site, and cost-effective way to create a bespoke gasket cord, saving both time and resources compared to waiting for a custom-sized seal to be manufactured.

Applications of O-Ring Cords

O-ring cords are used in a wide range of static sealing applications across various industrial sectors. Their ability to be customised makes them indispensable for sealing non-standard or oversized equipment where a pre-made seal is unavailable.

Large Industrial Flanges and Housings

O-ring cords are perfect for creating seals on large flanges, lids, and housings of industrial tanks, pressure vessels, and pumps. They ensure a leak-proof barrier against gases and liquids, which is crucial for safety and operational efficiency.

Hydraulic and Pneumatic Systems

While standard O-rings are common, a nitrile rubber O-ring cord is frequently used in hydraulic and pneumatic systems for creating static seals in valve manifolds, hydraulic cylinders, and other components where a precise and non-standard diameter is required.

OEM and Maintenance

Original Equipment Manufacturers (OEMs) and maintenance professionals rely on O-ring stock and cord for rapid prototyping and repair. They provide a quick solution for fitting seals to non-standard diameters in machinery, reducing downtime and operational costs.

Automotive and Aerospace

In the automotive and aerospace industries, a rubber cord seal can be used in custom applications for fluid and gas containment, especially in unique engine components or specialised equipment where a precise fit is paramount.

Types of O-Ring Cords

Selecting the right O-ring cord is essential for performance and durability. O-ring cords are categorised primarily by material, but also by their physical dimensions and function.

By Material

The material of an O-ring cord is the most critical factor, as it determines the seal's compatibility with chemicals, temperature, and pressure.

Nitrile (NBR): A common and versatile material, a nitrile O-ring cord offers excellent resistance to oils, fuels, and hydraulic fluids. It's a cost-effective choice for general-purpose industrial applications.
Silicone: A silicone O-ring cord is known for its wide operating temperature range, making it ideal for both high and low-temperature environments. It also has good flexibility and is a suitable material for food-grade applications.
Viton® (FKM): A Viton O-ring cord is the premium choice for applications involving aggressive chemicals, high heat, and harsh environments. It provides superior chemical resistance and durability.
Neoprene®: This material provides a good balance of properties, including resistance to weathering, ozone, and moderate oils, making it a versatile option for various sealing needs.
EPDM: EPDM is an excellent choice for outdoor applications, as it resists weathering, ozone, and steam. It is commonly used in brake fluids and hot water systems.

By Diameter

O-ring cords come in a variety of cross-sectional diameters to suit different groove sizes. The diameter is measured from one side of the circular profile to the other, with common sizes like 1.5mm, 2.0mm, 3.0mm, and 5.0mm readily available from the general O-ring stock to meet a wide range of sealing needs.

By Function

While all O-ring cords serve a similar purpose, they can be classified by their specific function within a system. A rubber cord seal or rubber O-ring cord can be used as a gasket cord to create a seal in a static application, such as between two stationary flanges. The versatility of the cord allows it to function as a custom-sized gasket, providing a tight barrier against leaks of gases or liquids.

How to Install O-Ring Cords

The process of installing a rubber O-ring cord requires precision to ensure a secure and long-lasting seal.

Measure and cut: Use a measuring tool to determine the exact length of gasket cord needed to fit snugly into the groove. Use a sharp, clean blade to make a straight, precise cut.
Join the ends: Apply a specialised adhesive to the two cut ends of the rubber cord and press them together firmly. A simple jig can be used to hold the ends in place for a few moments until the bond is secure.
Place in groove: Once the adhesive has cured, place the newly formed O-ring into the sealing groove, ensuring it sits correctly without any twists or kinks.
Compression: When the mating part is compressed against the seal, it creates a tight, reliable barrier.

How to Choose the Right O-Ring Cords

Selecting the right O-ring cord is a crucial step for the success of your application. Consider the following factors:

Chemical compatibility: The most important factor is the cord's material compatibility with the media it will be in contact with. Check the chemical resistance properties to prevent degradation of the seal.
Operating temperature: Ensure the material can withstand the minimum and maximum temperatures of your application.
Pressure: The rubber cord seal must be able to withstand the required pressure without extruding from the groove.
Size: The diameter of the cord should match the size of the sealing groove to achieve optimal compression.

Buy O-Ring Cords Online from RS Australia

RS is a top O-ring cord manufacturer, supplier, and distributor in Australia. We offer a broad O-ring stock from brands like RS PRO, Phoenix Contact and Saint-Gobain Industrial & Consumer Solutions. Our inventory also includes other essential workplace tools like electrical contactors, tank level sensors and heat shrink sleeves for your every need.

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