Specification summary of ISO 8434-2 as applied to jic 37-degree flare fittings: the dimensions the standard fixes, the full size range supplied, and the related designations commonly cross-referenced.
ISO 8434-2 — Scope
ISO 8434-2 specifies the dimensional requirements for jic 37-degree flare fittings.
Material, surface condition and any performance rating are set by separate documents specific to this part family — ISO 898-1 and ISO 898-2, which govern bolt and nut property classes, do not apply here.
Tolerance & Product Grades
Tolerances for jic 37-degree flare fittings are given as limits on the individual dimensions in the table rather than as a fastener product grade.
Where a general-tolerance class is cited on the drawing instead, it applies to the dimensions not otherwise toleranced.
Dimensions Specified by ISO 8434-2
| Dash size | Tube outside diameter | Thread (UNF) | Cone angle |
|---|---|---|---|
| -04 | 1/4 in | 7/16-20 | 37 degrees |
| -05 | 5/16 in | 1/2-20 | 37 degrees |
| -06 | 3/8 in | 9/16-18 | 37 degrees |
| -08 | 1/2 in | 3/4-16 | 37 degrees |
| -10 | 5/8 in | 7/8-14 | 37 degrees |
| -12 | 3/4 in | 1-1/16-12 | 37 degrees |
| -16 | 1 in | 1-5/16-12 | 37 degrees |
| -20 | 1-1/4 in | 1-5/8-12 | 37 degrees |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent JIC 37-Degree Flare Fittings page.
Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
Companion Standards
ISO 8434-2 controls only the geometry of jic 37-degree flare fittings. Surface finish is governed by separate finish standards (for example ISO 4042 for electroplating), and corrosion testing by ISO 9227 (neutral salt spray). Mechanical performance is set by the standards specific to this part family, not by ISO 898-1 or ISO 898-2, which apply to bolts, screws and nuts.
