Viton Piston Ring Question

[roxwellmax]

I'm intending to use a Viton 0 ring as a piston ring on a small engine I'm building. The bore is 20mm and the 0 ring size is 20mm OD 18mm ID 1mm cross section. Would anyone know the correct depth and width the ring groove should be? Any assistance would be very helpful.

Max

 

[Tin Falcon]

Bore diameter 20 mm +.05mm - 0.0
Groove diameter 18 mm + 0.0 -0.05 mm
groove width 1mm.
Do not feel bad can seem very confusing.

I suggest getting a copy of the machinery's handbook used copies not too expensive or download a pdf version. I recommend one old and out of copyright. Great for looking up this type of info and explains it well.

And an online calculator like this one is helpful as well.

http://www.applerubber.com/oring-gland-calculator/?gclid=CPzShd_2-LwCFUdk7AodTiwAxQ

O-ring charts help as well

http://www.prepol.com/PPE-Uploads/Oring_sizes_AS568.pdf
tin

 

[mu38&Bg#]

Is no radial compression of the o-ring typical for piston o-rings, I'm not sure? I don't think it's nearly as much as standard recommendations you'll find in a handbook. The standard is 20-30% squeeze ( of actual cross section) in the radial direction. The Parker handbook is an excellent resource.

 

[Tin Falcon]

Well I came up with the best info I could. If you look at the calculator and click on dynamic piston seal it shows a 10% to 30 % seal compression. so increase the groove diameter by 0.2 to 0.6 mm .

tin

 

[gus]

Is no radial compression of the o-ring typical for piston o-rings, I'm not sure? I don't think it's nearly as much as standard recommendations you'll find in a handbook. The standard is 20-30% squeeze ( of actual cross section) in the radial direction. The Parker handbook is an excellent resource.

Thanks for the Parker Cataloque. My encounter using ''O'' Rings been disastrous.
Will be using Viton O Rings for IC engines I plan to build.

 

[robcas631]

Once you understand the math behind O rings it's easy.

 

[robcas631]

Tin,

I bought this book. Great info!