Standard O-Ring Size Chart
Download the O-Ring Size Chart to view standard sizes (O-rings are measured in millimeters).
How to Measure O-Rings
‘O' ring 1) Identify appropriate Chart and part number for existing ‘O' ring. (Note: If a standard ‘O' ring has been used on a non-standard shaft or cylinder — ie, compressed or stretched into place — the equivalent standard back-up ring must not be used as it cannot be stretched or squeezed in the same way.). Order O-Rings online Millions of AS568 O-Rings, Metric O-Rings and Hydraulic Seals Online. Live chat for O-Ring Sales and service. Our basic stock compound list includes over 30 o-ring compounds making us one of the most diverse O-Ring Suppplier in the Global O-Ring market.
O-Rings are one of the most common types of seals in the world. With an unlimited number of possible manufacturing sizes, they are used various applications across industries. These round mechanical seals keep gas or liquid from passing through an opening but over time, they may wear out and require replacement. If you're planning to replace an O-ring, a good fit is critical for successful sealing.
Below are the steps to take to properly measure for a new or replacement O-Ring.
- Place the O-ring on a clean, flat, level surface.
- Determine the inside diameter by using a ruler to measure from one inner edge to another.
- Use a ruler to measure the diameter, from one outer corner of the O-ring to the other outer corner.
- Finally, measure the cross-section. Place the O-ring into a vernier caliper. Lightly clamp the jaws of the caliper onto the O-ring, but do not compress it. Record the thickness of the ring (the cross-section, see image for reference).
More Resources and Quick Links
- Shop our selection of popular brand O-Rings, like Alfas, Buna, EPR, Viton, and more!
- Check out this post, A Simple Guide to Selection an O-ring for more detailed information.
- Need Parker O-Ring Sizing Gauges? We have those!
- Complete your set up with the Parker O-Ring Installation and Extraction Tools
For more information about O-ring sizes, applications, or orders, contact our team!
O-ring Groove Calculator
The O-ring groove calculator enables engineers to specify an O-ring groove for any given O-ring or vice versa calculates the best suitable size O-ring for any given groove.
The calculator takes all relevant parameters into account like:
- O-Ring squeeze
- Free groove volume
- O-Ring inner diameter stretch, outer diameter squeeze
- Thermal
- Chemical swell of the rubber material
- Thermal expansion of all available elastomers and mating construction parts materials
Now online:
Available now our user friendly and easy to use theO-ring Groove Calculator.
ERIKS O-Ring Groove Calculator features the calculation of:
Groove dimensions for the use of a specific O-Ring
O-Ring dimensions for the use in a specific groove
- Evaluation of both, any combination of O-Ring and groove
A unique calculator
Below are the steps to take to properly measure for a new or replacement O-Ring.
- Place the O-ring on a clean, flat, level surface.
- Determine the inside diameter by using a ruler to measure from one inner edge to another.
- Use a ruler to measure the diameter, from one outer corner of the O-ring to the other outer corner.
- Finally, measure the cross-section. Place the O-ring into a vernier caliper. Lightly clamp the jaws of the caliper onto the O-ring, but do not compress it. Record the thickness of the ring (the cross-section, see image for reference).
More Resources and Quick Links
- Shop our selection of popular brand O-Rings, like Alfas, Buna, EPR, Viton, and more!
- Check out this post, A Simple Guide to Selection an O-ring for more detailed information.
- Need Parker O-Ring Sizing Gauges? We have those!
- Complete your set up with the Parker O-Ring Installation and Extraction Tools
For more information about O-ring sizes, applications, or orders, contact our team!
O-ring Groove Calculator
The O-ring groove calculator enables engineers to specify an O-ring groove for any given O-ring or vice versa calculates the best suitable size O-ring for any given groove.
The calculator takes all relevant parameters into account like:
- O-Ring squeeze
- Free groove volume
- O-Ring inner diameter stretch, outer diameter squeeze
- Thermal
- Chemical swell of the rubber material
- Thermal expansion of all available elastomers and mating construction parts materials
Now online:
Available now our user friendly and easy to use theO-ring Groove Calculator.
ERIKS O-Ring Groove Calculator features the calculation of:
Groove dimensions for the use of a specific O-Ring
O-Ring dimensions for the use in a specific groove
- Evaluation of both, any combination of O-Ring and groove
A unique calculator
Worldwide unique online calculation tool taking into consideration of the thermal expansion of the mating construction parts materials. As well as the chemical volume swell or shrinkage of the O-Ring.
Choose between over 30 construction part materials and 11 O-Ring compounds!
Ask ERIKS
O'ring Groove Chart
For more information on the O-ring Groove Calculatoror other products please visit ourcontact pageor fill the 'Ask ERIKS' form on the upper-right corner.
