O-rings are essential components used in many industries to provide a seal between two surfaces. They come in various sizes, shapes, and materials to suit different applications. In Japan, the Japanese Industrial Standards (JIS B 2401) defines the specifications for O-rings used in various industries. In this blog, we will discuss what JIS O-rings are, their specifications, and their advantages.
What are JIS O-Rings?
JIS O-rings are O-rings manufactured in accordance with the Japanese Industrial Standards. These standards provide specifications for dimensions of O-rings used in various industries, such as automotive, aerospace, and electronics. Each of the 261 standard JIS sizes has a specific JIS reference number attached to it that is used to look up the cross sectional diameter (CS) and inside diameter (ID).
JIS O-Ring Specifications
The JIS defines O-ring specifications in terms of their dimensions, material, and performance. Some of the specifications for JIS O-rings include:
Dimension: JIS O-rings come in different sizes, ranging from 2.5mm to 1044mm in diameter, and 1.5mm to 10mm in cross-section diameter. If you are interested in seeing a full list of sizes, see our JIS O-rings page.
Material: The JIS specifies the materials used to manufacture O-rings based on their intended application. Some common materials used in JIS O-rings include Nitrile Rubber (NBR), Fluorocarbon Rubber (FKM), and Silicone Rubber (VMQ). However, JIS is frequently used simply to define the size of an O-ring, not necessarily its material characteristics. For example, a specialty application may require a JIS size manufactured from a specialty material that wasn’t accounted for in the JIS specification.
Performance: The JIS also specifies the performance requirements for O-rings, such as their ability to withstand high and low temperatures, pressure, and chemical resistance. However, JIS is frequently used simply to define the size of an O-ring, not necessarily its material characteristics. For example, a specialty application may require a JIS size manufactured from a specialty material that wasn’t accounted for in the JIS specification.
Advantages of JIS O-Rings
JIS O-rings offer several advantages over other types of O-rings. These include:
Consistency: JIS O-rings are manufactured to strict standards, ensuring consistent dimensions and material properties. (However, JIS is frequently used simply to define the size of an O-ring, not necessarily its material characteristics.)
Quality: JIS O-rings are subjected to rigorous testing to ensure they meet the required specifications, ensuring a high level of quality.
Compatibility: JIS O-rings are compatible with other JIS-approved components, ensuring a proper fit and sealing.
Availability: Since JIS O-rings are widely used in Japan and other countries, they are readily available from many suppliers.
JIS O-rings are essential components used in various industries to provide a reliable seal between two surfaces. They are manufactured in accordance with strict Japanese Industrial Standards, ensuring consistent dimensions, material properties, and performance. JIS O-rings offer several advantages, such as compatibility with other JIS-approved components, availability, and quality. If you are looking for O-rings for your application, consider using JIS O-rings to ensure reliable and consistent performance.
Where can I get JIS parts?
With the request a quote page, you can get directly in contact with our team of specialists who will help get you the parts you need.
 Cc. (2023, December 4). JIS B 2401 O-Rings: The Japanese standard. Canyon Components. https://www.canyoncomponents.com/post/jis-o-rings-the-japanese-standard
 JIS B 2401-1:2012. (n.d.).
 JIS B 2401 O-ring standard specifications (metric) - O-ring cross reference - Topics - Gregory Bender. (n.d.). https://www.thisoldtractor.com/o-rings_jisb2401.html