O'ring Cord

O'ring cord cross section

O’ring cord cross section

O’ring Cord

O’ring cord is a simple round section rubber extrusion. There are many uses for o’ring cord but is most commonly cut to a precision length and joined to make an o’ring. This is handy when odd sized o’rings are urgently required and not available or when the required diameter is larger than what can be fully moulded. Though keep in mind that being an extrusion, cross sectional tolerances are larger than a fully moulded seal (see table below) and joined o’rings are suitable as a static seal only.
 
Sealing Australia stocks a wide range of o’ring cord in various compounds, hardness’s and cross sections.

 

Range of compounds

  • NBR (Nitrile)
  • FKM (Viton®)
  • EPDM
  • Silicone
  • Neoprene
  • Polyurethane

Range of Hardness’s

Measured in Shore A Durometer

  • 50D
  • 60D
  • 70D
  • 90D

Other hardness’s are available.

Range of cross sections

From 1.0mm to 50.0mm, including all popular imperial and metric o’ring cross sections.

Cross Sectional Tolerances

Sealing Australia’s cord stock is manufactured to RMA Class E1 High Precision Tolerance, the highest standard for o’ring cord tolerance.

RMA E1 (High Precision) Tolerance

Diameter (Inch) ± Diameter (mm) ±
.000 – .060 ±.006 0.0 – 1.5 ±0.15
.060 – .100 ±.008 1.5 – 2.5 ±0.20
.100 – .160 ±.010 2.5 – 4.0 ±0.25
.160 – .250 ±.014 4.0 – 6.3 ±0.35
.250 – .390 ±.016 6.3 – 10 ±0.40
.390 – .630 ±.020 10 – 16 ±0.50
.630 – .980 ±.027 16 – 25 ±0.70
.980 – 1.570 ±.031 25 – 40 ±0.80
1.570 – 2.480 ±.039 40 – 63 ±1.00
2.480 – 3.940 ±.051 63 – 100 ±1.30