Specification summary of DIN 2353 as applied to hydraulic compression fittings: the dimensions the standard fixes, the full size range supplied, and the related designations commonly cross-referenced.
DIN 2353 — Scope
DIN 2353 specifies the dimensional requirements for hydraulic compression 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 hydraulic compression 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 DIN 2353
| Tube OD (mm) | Nut length L (mm) | Nut width across flats (mm) | Tube bore (mm) | Max working pressure (bar) | Mating thread | Reference standard | Notes |
|---|---|---|---|---|---|---|---|
| 4 | 22 | 13 | 8 | 400 | M10x1 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 5 | 24 | 14 | 9 | 400 | M12x1.5 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 6 | 27 | 17 | 11 | 400 | M14x1.5 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 8 | 30 | 19 | 13 | 400 | M16x1.5 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 10 | 33 | 22 | 16 | 400 | M18x1.5 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 12 | 36 | 24 | 18 | 315 | M22x1.5 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 14 | 39 | 27 | 20 | 315 | M26x1.5 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 15 | 39 | 27 | 20 | 315 | M26x1.5 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 16 | 42 | 30 | 22 | 315 | M26x1.5 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 18 | 45 | 32 | 25 | 250 | M30x2 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 20 | 48 | 36 | 27 | 250 | M30x2 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 22 | 51 | 38 | 30 | 250 | M36x2 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 25 | 55 | 41 | 32 | 250 | M36x2 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 28 | 58 | 46 | 36 | 160 | M42x2 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 30 | 60 | 48 | 38 | 160 | M42x2 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 35 | 66 | 55 | 44 | 160 | M52x2 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 38 | 69 | 58 | 47 | 160 | M52x2 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
| 42 | 74 | 65 | 52 | 100 | M60x2 | DIN 2353 / ISO 8434-1 | Compression hydraulic fitting |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Hydraulic Compression Fittings page. Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
Companion Standards
DIN 2353 controls only the geometry of hydraulic compression 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.


