How Many Mm is Size O Ring

16 Apr.,2025

 

When it comes to O-rings, understanding their sizes is crucial for a variety of applications in engineering, plumbing, and automotive sectors. One of the most common inquiries related to these vital components is: how many mm is size O ring?

If you are looking for more details, kindly visit How Many Mm is Size O Ring.

O-rings are circular seals that can be made from various materials such as rubber or silicone, and they serve as a barrier to prevent fluid or gas leaks. Their sizing is fundamental to ensuring they fit correctly in their intended application. The sizing standards for O-rings can often be a source of confusion, especially when converting inches to millimeters.

O-Ring Size Specifications

The dimensions of an O-ring are typically classified by their inner diameter (ID), outer diameter (OD), and cross-section (CS). For the specific query of how many mm is size O ring, the sizing chart published by the AS568A standard is beneficial. This standard outlines various sizes of O-rings used primarily in the United States and corresponds roughly to specific millimeter dimensions.

AS568A Standard Sizes

According to the AS568A standard, here are some common O-ring sizes converted from inches to millimeters:

  • Size A: 0.139 inches ID (3.53 mm), 0.210 inches CS (5.33 mm)
  • Size B: 0.234 inches ID (5.94 mm), 0.103 inches CS (2.62 mm)
  • Size C: 0.350 inches ID (8.89 mm), 0.070 inches CS (1.78 mm)
  • Size D: 0.500 inches ID (12.70 mm), 0.070 inches CS (1.78 mm)
  • Size E: 0.625 inches ID (15.88 mm), 0.103 inches CS (2.62 mm)

If you're wondering how many mm is size O ring, it is essential to consult the sizing chart appropriate for your application to determine the exact dimensions needed.

Other Sizing Standards

In addition to the AS568A standards, there are several international standards that provide guidelines for O-ring sizing, including ISO 3601 and DIN 3771. ISO 3601 has a range of sizes and specifies them in both metric and imperial units, allowing users globally to find the specific size they need. In this specification, you can find O-rings ranging from very small sizes (like 1 mm ID) to larger sizes (over 100 mm ID).

Conversion Chart for O-Ring Sizes

As mentioned earlier, converting O-ring sizes from inches to millimeters can sometimes create challenges. Here's a simple conversion reference:

  • 1 inch = 25.4 mm
  • Therefore, to convert inches to mm, you multiply the inch measurement by 25.4.

This conversion method is essential if you're using a sizing chart that provides measurements in inches and you need to understand how many mm is size O ring in a global context.

Material Considerations

When selecting an O-ring, consider the material alongside its size. Common materials include Nitrile (Buna-N), Silicone, EPDM, and Viton. Each material has different properties and is suited for different applications depending on temperature and chemical compatibility.

Importance of Proper Sizing

Using an O-ring of incorrect size can lead to failures in sealing, resulting in leaks that can be costly and dangerous. Understanding how many mm is size O ring can save you time and money by ensuring you choose the right size for your project's needs.

Finding the Right O-Ring Size

To find the exact size of the O-ring you're looking for, refer to a trusted manufacturer's specifications or online resources that provide comprehensive size charts. Websites specializing in seal products often have calculators that help convert sizes based on your needs.

In summary, when you ask how many mm is size O ring, you are referring to a precise measurement defined by industry standards. Ensure to check the correct sizing charts and standards applicable to your O-ring selection to achieve optimal performance.

For reliable reference, you can consult the AS568A specification available through resources like the Society of Automotive Engineers (SAE) or specialized O-ring suppliers.

For more information, please visit O Ring Gasket.