O-Ring Gland Calculator

Inputs

O-ring free ID (ID)

Inside diameter of the free O-ring before installation.

Cross section (CS)

O-ring cord diameter.

Installed diameter (D_i)

Diameter the O-ring stretches over in the gland.

Gland depth (h)

Radial gland depth after installation; this sets squeeze.

Gland width (w)

Axial groove width available to the O-ring.

Default result

Squeeze(S)

20%

Pass

Squeeze = (cross section - gland depth) / cross section.

Typical static radial target is roughly 10-30%.

Also computed

Gland fill(GF)61.36%

Gland fill = O-ring cross-section area / gland rectangular area.

Many static glands target below about 85% fill.

Stretch(ST)2%

Keep stretch modest; large stretch reduces cross section.

O-ring area(A_o)3.142mm²

Gland area(A_g)5.12mm²

Compressed height(h)1.6mm

Method notes 3 notes

This is a geometric gland check for squeeze, stretch and fill. It does not replace the Parker/AS568 or manufacturer gland tables.
High gland fill leaves little room for thermal expansion, swell and tolerance stack-up; fill above about 85% is usually a warning for static glands.
Dynamic seals, pressure direction, extrusion gaps, backup rings, compound swell, temperature, surface finish and friction are not included.