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In the hydraulic industry, hydraulic fittings are key components that connect pipelines, equipment and components. But for many people new to the industry, the numbering and naming of hydraulic connectors can be confusing. Correct understanding and use of these numbers is a prerequisite for ensuring stable system operation and avoiding mismatches. This article will give you an in-depth explanation of the numbering and naming system of hydraulic joints to help you avoid misunderstandings in actual operations.
Almost all china hydraulic fittings factories are using the same code system, which consists of nine numbers. Understand this naming rule will make it easier to purchase hydraulic hose fittings in China.
一、Core number format
XXXXX-XX-XX T
X is a number that represents different meanings. If there is T, it means hanging nut, if there is no T, it means lock nut or no nut.
First five digit numbering rules
XXXXX-XX-XX
| The first Head type | The second Thread system | the third Sealing surface form | The fourth Curvature | The fifth Core tail type |
| 1 male thread | 0 metric | 0 no meaning | 1 straight | 1 braided hose |
| 2 swaged nut | 1 international metric | 1 multiseal | 4 45° | 2 4 layers spiral hose |
| 2 BSP thread | 2 flat seat | 9 90 ° | 2 6 layers spiral hose | |
| 3 BSPT thread | 3 flat with o-ring | |||
| 5 Bite type | 4 ORFS Thread | 4 24° CONE/SEAT L.T | ||
| 6 interlock type | 5 NPT Thread | 5 24° CONE/SEAT H.T | ||
| 7 banjo type | 6 JIC thread | 6 60°CONE/SEAT | ||
| 8 flange type | 7 SAE thread | 7 74° CONE/SEAT | ||
| 9 double connector | 8 JIS metric thread | 8 90° CONE/SEAT | ||
| 9 JIS BSPP thread |
XXXXX-XX-XX
| Size code | 02 | 04 | 05 | 06 | 08 | 10 | 12 | 16 | 20 | 24 | 32 |
| BSP | G1/8″× 28 | G1/4″× 19 | G3/8″× 19 | G1/2″× 14 | G5/8″× 14 | G3/4″× 14 | G1″× 11 | G1.1/4″× 11 | G1.1/2″× 11 | G2″× 11 | |
| BSPT | R1/8″× 28 | R1/4″× 19 | R3/8″× 19 | R1/2″× 14 | R3/4″× 14 | R1″× 11 | R1.1/4″× 11 | R1.1/2″× 11 | R2″× 11 | ||
| NPT | Z1/8″× 27 | Z1/4″× 18 | Z3/8″× 18 | Z1/2″× 14 | Z3/4″× 14 | Z1″× 11.5 | Z1.1/4″× 11.5 | Z1.1/2″× 11.5 | Z2″× 11.5 | ||
| JIC | 7/16″× 20 | 1/2″× 20 | 9/16″× 18 | 3/4″× 16 | 7/8″× 14 | 1.1/16″× 12 | 1.5/16″× 12 | 1.5/8″× 12 | 1.7/8″× 12 | 2.1/2″× 12 | |
| ORFS | 9/16″× 18 | 11/16″× 16 | 13/16″× 16 | 1″× 14 | 1.3/16″× 12 | 1.7/16″× 12 | 1.11/16″× 12 | 2″× 12 | |||
| Flange | 1/2″ | 3/4″ | 1″ | 1.1/4″ | 1.1/2″ | 2″ |
Metric connection specifications and dimensions
| Size code | 12 | 14 | 16 | 18 | 20 | 22 | 24 | 26 | 27 |
| Metric thread | 12 × 1.5 （ 1.25 ） | 14 × 1.5 | 16 × 1.5 | 18 × 1.5 | 20 × 1.5 | 22 × 1.5 | 24 × 1.5 （ 2 | 26 × 1.5 （ 2 ） | 27 × 1.5 （ 2 ） |
| Code | 30 | 33 | 36 | 39 | 42 | 45 | 52 | 64 | |
| Metric Thread | 30 × 1.5 （ 2 ） | 33 × 1.5 （ 2 ） | 36 × 2 | 39 × 2 | 42 × 2 | 45 × 2 | 52 × 2 | 64 × 2 |
XXXXX-XX-XX
| code | 04 | 05 | 06 | 08 | 10 | 12 | 16 | 20 | 24 | 28 | 32 | 40 |
| size | 6 | 8 | 10 | 12 | 16 | 20 | 25 | 32 | 38 | 45 | 50 | 64 |
| The first Ferrule | The second Production standard of hose | The third Hose layer | The fouth Skiving or no-skving | The fifth Speical specification |
| 0 all ferrules | 0 imported hose（ SAE ） | 0 fiber braided | 0 skiving | 0 no meaning or 4SP |
| 1 China hose（ GB ） | 1 sigle steel wire braided | 1 no-skiving | 1 4SH (Enhanced) | |
| 2 two layers steel wire braided | 8 thermoplastic pipe | |||
| 3 three layers steel wire braided | ||||
| 4 four layer steel wire spiral | ||||
| 5 two layers steel wire spiral | ||||
| 6 six layers steel wire spiral |
| 3000 light type FL | 08 | 12 | 16 | 20 | 24 | 32 |
| imperial | 1/2″ | 3/4″ | 1″ | 1.1/4″ | 1.1/2″ | 2″ |
| metric | 30.2 | 38.1 | 44.4 | 50.8 | 60.3 | 71.4 |
| 6000 heavy type FS | 08 | 12 | 16 | 20 | 24 | 32 |
| imperial | 1/2″ | 3/4″ | 1″ | 1.1/4″ | 1.1/2″ | 2″ |
| metric | 31.7 | 41.3 | 47.6 | 54 | 63.5 | 79.4 |
二、Ferrule numbering rules
XXXXX-XX
First five digit numbering rules
| Code | 04 | 05 | 06 | 08 | 10 | 12 | 16 | 20 | 24 | 28 | 32 | 40 |
| I.D. | 6 | 8 | 10 | 12 | 16 | 20 | 25 | 32 | 38 | 45 | 50 | 64 |
