The importance of choosing the right O-ring

TECHNICAL GUIDE

The O-rings are critical components in a wide range of industrial applications. Their main function is to provide efficient, reliable, and durable sealing, preventing leaks of liquids and gases. However, for an O-ring to function properly for the maximum possible time, it is crucial to consider these factors:

MEASUREMENTS

The measurement of an O-ring is fundamental to its correct operation. The two key dimensions are the inner diameter and the outer diameter. The correct determination of the cross-sectional thickness (also known as the torus) is essential for effective sealing.

Choosing an O-ring with incorrect measurements can result in ineffective sealing, premature wear, and system failures.

• Inner diameter: It must match the diameter of the groove where the O-ring will be installed.
• Outer diameter: With the inner diameter and the torus correctly calculated, proper fit and operation are ensured.

Proper installation is also vital. Clean the groove and lightly lubricate the O-ring to facilitate its placement without damage. Using appropriate tools will prevent cuts or excessive stretching.

> See: TOLERANCE ON TORUS | TOLERANCE ON INNER DIAMETER | INTERNATIONAL STANDARDS MEASUREMENTS

MATERIALS

The material of the O-ring should be selected based on the operating environment. Different materials offer various chemical and thermal resistances.

• NBR: Excellent for oil and water applications at temperatures between -40°C and 120°C.
• Viton: Ideal for aggressive chemical environments and high temperatures, up to 250°C.
• Silicone: Suitable for applications with wide temperature ranges (-60°C to 230°C), but not resistant to fuels.
• EPDM: Resistant to ozone, hot water, and steam, useful in drinking water applications.

Do you know how O-rings will behave when in contact with different materials? Choosing the right material for an O-ring is crucial to ensuring its performance and durability in various applications. The compatibility of the O-ring material with the specific fluids, gases, and environments to which it will be exposed will determine its effectiveness and lifespan.

> See: MATERIAL COMPATIBILITY TABLE

HARDNESS

The hardness of an O-ring is measured on the Shore A scale. This property determines the O-ring's ability to withstand pressure and abrasion.

• Low hardness (30-50 Shore A): Improves sealing in low-pressure applications and less precise tolerances.
• Medium hardness (60-70 Shore A): Commonly used in a variety of industrial applications.
• High hardness (80-90 Shore A): Ideal for high-pressure and abrasive environments.

APPROVALS

Depending on the industry and application, O-rings may need to meet various approvals and standards.

• FDA: For applications in the food and pharmaceutical industries.
• ISO 9001: Ensures the quality of the manufacturing process.
• ROHS: Certification for the restriction of hazardous substances, important in the electronics industry.

At JIOrings, we currently have over 1000 compounds, many of which are approved by our suppliers in certified laboratories or compliant with the most common international standards.

> See: APPROVED COMPOUNDS

COLOR

The color of O-rings may seem trivial, but it is essential in certain applications.

• Identification: Colors help to quickly identify the material of the O-ring.
• Visibility: In low-light or hard-to-access environments, color can facilitate inspection and maintenance.
• Compatibility: In the food and pharmaceutical industries, specific colors may be required to comply with hygiene and safety standards.

> See: AVAILABLE RAL COLOR TABLE

Choosing the right O-ring involves a detailed analysis of the operating conditions and the system's technical specifications. By carefully considering measurements, material, hardness, approvals, and color, optimal and prolonged equipment performance can be ensured. Incorrect selection can result in costly and dangerous failures, while the correct choice guarantees effective and long-lasting sealing.