ISO 3601-4:2008
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Fluid power systems -- O-rings -- Part 4: Anti-extrusion rings (back-up rings)

(Not available in French)

This standard was last reviewed and confirmed* in 2013.

*Therefore this version remains current


ISO 3601-4:2008 specifies dimensions and tolerances for five types of anti-extrusion rings, which are also known as back-up rings:

  1. spiral type (T1);
  2. angle cut type (T2);
  3. solid type (T3);
  4. angle cut concave type (T4);
  5. solid concave type (T5).

These anti-extrusion rings are for use with selected O-ring sizes as specified in ISO 3601-1 and the relevant housing dimensions specified in ISO 3601-2.


  • Document published on: 2008-06-01
    Edition: 1 (Monolingual) ICS: 83.140.50; 23.100.60
    Status: Published Stage: 90.93 (2013-03-28)
    TC/SC: ISO/TC 131/SC 7 Number of Pages: 11
  • This standard has not been revised

  • No corrigenda or amendments available

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