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spencer wilson
spencer wilson
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I think I've figured this out (through some discussion with a helpful physicist). Yes, of course it's possible to seal a perfectly smooth surface.

The purpose of roughness in o-ring sealing is twofold:

  1. Retention-- roughness helps o-rings remained retained in their groove or other retention feature via friction.

  2. Stress concentration -- roughness provides local stress concentrations to productproduce a better seal. A perfectly flat surface will seal, but may require higher sealing force than an appropriately rough surface due to lack of local stress concentrations in the o-ring. There is an optimal roughness which is nonzero-- too rough and there's a chance you will have leaks across your sealing surface. Too smooth and you're suboptimal with respect to sealing force.

I think I've figured this out (through some discussion with a helpful physicist). Yes, of course it's possible to seal a perfectly smooth surface.

The purpose of roughness in o-ring sealing is twofold:

  1. Retention-- roughness helps o-rings remained retained in their groove or other retention feature via friction.

  2. Stress concentration -- roughness provides local stress concentrations to product a better seal. A perfectly flat surface will seal, but may require higher sealing force than an appropriately rough surface due to lack of local stress concentrations in the o-ring. There is an optimal roughness which is nonzero-- too rough and there's a chance you will have leaks across your sealing surface. Too smooth and you're suboptimal with respect to sealing force.

I think I've figured this out (through some discussion with a helpful physicist). Yes, of course it's possible to seal a perfectly smooth surface.

The purpose of roughness in o-ring sealing is twofold:

  1. Retention-- roughness helps o-rings remained retained in their groove or other retention feature via friction.

  2. Stress concentration -- roughness provides local stress concentrations to produce a better seal. A perfectly flat surface will seal, but may require higher sealing force than an appropriately rough surface due to lack of local stress concentrations in the o-ring. There is an optimal roughness which is nonzero-- too rough and there's a chance you will have leaks across your sealing surface. Too smooth and you're suboptimal with respect to sealing force.

Source Link
spencer wilson
spencer wilson
  • 31
  • 2

I think I've figured this out (through some discussion with a helpful physicist). Yes, of course it's possible to seal a perfectly smooth surface.

The purpose of roughness in o-ring sealing is twofold:

  1. Retention-- roughness helps o-rings remained retained in their groove or other retention feature via friction.

  2. Stress concentration -- roughness provides local stress concentrations to product a better seal. A perfectly flat surface will seal, but may require higher sealing force than an appropriately rough surface due to lack of local stress concentrations in the o-ring. There is an optimal roughness which is nonzero-- too rough and there's a chance you will have leaks across your sealing surface. Too smooth and you're suboptimal with respect to sealing force.