Great Dane excavating co.

[Cooper]

I use 1/16” orings. Actual size of .063” ring is .070. I cut .063 groove and size off of Inside diameters or outside diameter. Depending on tube or rod. Tube is measured by outside diameter , pipe is measured by inside diameter. I’ve found if you try and compress orings too much they are too tight for a low pressure hydraulic system like we have. Say I have a cylinder rod of .25 I will usually use a oring of .25 inner diameter. And account for the actual size of oring to be the compression. And the groove is the static part the rod is the seal part. I’ll try and find some info I found a while back for you.

[Zabco]

Originally Posted by Cooper

I use 1/16” orings. Actual size of .063” ring is .070. I cut .063 groove and size off of Inside diameters or outside diameter. Depending on tube or rod. Tube is measured by outside diameter , pipe is measured by inside diameter. I’ve found if you try and compress orings too much they are too tight for a low pressure hydraulic system like we have. Say I have a cylinder rod of .25 I will usually use a oring of .25 inner diameter. And account for the actual size of oring to be the compression. And the groove is the static part the rod is the seal part. I’ll try and find some info I found a while back for you.

Thank you very much, great information. I've never done hydraulics before but have started on a project that will require me to fabricate my own cylinders as what I need to stay reasonably to scale is not available. I knew that O-rings were made to standardized sizes but no idea how to figure out how much compression was needed to make them work properly. Have you ever tried X or quatro rings? From what I've read on them they can be used as direct replacements for O-rings as they are the same size and could provide a better seal at lower compression or pressure.