Hydraulic adapters and Malleable iron fittings are Identified with Number Codes representing each size, while brass pipe thread fittings use Letter Codes to represent each size, both systems are commonly used throughout the industry.
| Nominal Thread Size (Inches.) | SAE Number Dash Sizes | NPT Letter Dash Sizes | Fraction Size | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1/16 | 1 | 0.0625 | ||||||||
| 1/8 | 2 | A | 0.1250 | |||||||
| 3/16 | 3 | 0.1875 | ||||||||
| 1/4 | 4 | B | 0.2500 | |||||||
| 5/16 | 5 | 0.3125 | ||||||||
| 3/8 | 6 | C | 0.3750 | |||||||
| 1/2 | 8 | D | 0.5000 | |||||||
| 5/8 | 10 | 0.6250 | ||||||||
| 3/4 | 12 | E | 0.7500 | |||||||
| 7/8 | 14 | 0.8750 | ||||||||
| 1 | 16 | F | 1.000 | |||||||
| 1 1/4 | 20 | G | 1.250 | |||||||
| 1 1/2 | 24 | H | 1.500 | |||||||
| 2 | 32 | I | 2.000 | |||||||
| 2 1/2 | 40 | J | 2.500 | |||||||
| 3 | 48 | K | 3.000 | |||||||
| 4 | 64 | L | 4.000 | |||||||
Note: In the case of a fitting that is a jump size, it is recommend that the lower pressure of the two ends must be recognized as the working pressure rating for that fitting. This is also the case if the fitting has one or more different style ends. For example, straight threads to pipe threads. In this case it is also recommended that the lower pressure rating of the two different style ends must be recognized as the working pressure rating for that fitting.
| Nom SAE Dash Size | Nom Tube O.D. in M.M. | Nom Tube O.D. in Inch | Straight Thread Size | Nom Pipe Size | Rigid SAE St. Thread Unions & Bulkhead MPa | Rigid SAE St. Thread Unions & Bulkhead PSI | Adjustable SAE Std. Thread & Female Swivel MPa | Adjustable SAE Std. Thread & Female Swivel PSI | Fittings with Pipe Thread MPa | Fittings with Pipe Thread PSI | NPSM Std. Pipe Thread Maximum Operating Pressure MPa | NPSM Std. Pipe Thread MaximumOperating Pressure MPa |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2 | 3.18 | 0.250 | 5/16 24 | 1/8 | 34.5 | 5,000 | 34.5 | 5,000 | 34.5 | 5,000 | 34.5 | 5,000 |
| 3 | 4.76 | 0.188 | 3/8 24 | 1/8 | 34.5 | 5,000 | 34.5 | 5,000 | 34.5 | 5,000 | ||
| 4 | 6.35 | 0.250 | 7/16 20 | 1/8 | 34.5 | 5,000 | 31.0 | 4,500 | 34.5 | 5,000 | 34.5 | 5,000 |
| 5 | 7.94 | 0.313 | 1/2 20 | 1/8 | 34.5 | 5,000 | 27.5 | 4,000 | 34.5 | 5,000 | ||
| 6 | 9.52 | 0.375 | 9/16 18 | 1/4 | 34.5 | 5,000 | 27.5 | 4,000 | 27.5 | 4,000 | 27.5 | 4,000 |
| 8 | 12.70 | 0.500 | 3/4 16 | 3/8 | 31.0 | 4,500 | 27.5 | 4,000 | 21.0 | 3,000 | 24.1 | 3,500 |
| 10 | 15.88 | 0.625 | 7/8 14 | 1/2 | 24.0 | 3,500 | 21.0 | 3,000 | 21.0 | 3,000 | ||
| 12 | 19.05 | 0.750 | 1 1/16 12 | 3/4 | 24.0 | 3,500 | 21.0 | 3,000 | 17.0 | 2,500 | 15.5 | 2,250 |
| 14 | 22.22 | 0.875 | 1 3/16 12 | 3/4 | 21.0 | 3,000 | 17.0 | 2,500 | 17.0 | 2,500 | ||
| 16 | 25.40 | 1.000 | 1 5/16 12 | 1 | 21.0 | 3,000 | 17.0 | 2,500 | 14.0 | 2,000 | 13.8 | 2,000 |
| 20 | 31.75 | 1.250 | 1 5/8 12 | 1 1/4 | 17.0 | 2,500 | 14.0 | 2,000 | 8.0 | 1,150 | 11.2 | 1,625 |
| 24 | 38.10 | 1.500 | 1 7/8 12 | 1 1/2 | 14.0 | 2,000 | 10.5 | 1,500 | 7.0 | 1,000 | 8.6 | 1,250 |
| 32 | 50.30 | 2.000 | 2 1/2 12 | 2 | 10.5 | 1,500 | 8.0 | 1,125 | 7.0 | 1,000 | 7.8 | 1,125 |
Note: In the case of a fitting that is a jump size, it is recommend that the lower pressure of the two ends must be recognized as the working pressure rating for that fitting. This is also the case if the fitting has one or more different style ends. For example, straight threads to pipe threads. In this case it is also recommended that the lower pressure rating of the two different style ends must be recognized as the working pressure rating for that fitting.
| Nominal Pipe Size | Fittings with Pipe Thread MPa | Fittings with Pipe Thread PSI | Max. Oper. Pressure MPa | NPSM Std. Pipe Thread Maximum Operating Pressure PSI | |||
|---|---|---|---|---|---|---|---|
| 1/8 | 34.5 | 5,000 | 34.5 | 5,000 | |||
| 1/4 | 27.5 | 4,000 | 27.5 | 4,000 | |||
| 3/8 | 21.0 | 3,000 | 24.1 | 3,500 | |||
| 1/2 | 21.0 | 3,000 | |||||
| 3/4 | 17.0 | 2,500 | 15.5 | 2,250 | |||
| 1 | 14.0 | 2,000 | 13.8 | 2,000 | |||
| 1 1/4 | 8.0 | 1,150 | 11.2 | 1,625 | |||
| 1 1/2 | 7.0 | 1,000 | 8.6 | 1,250 | |||
| 2 | 7.0 | 1,000 | 7.8 | 1,125 | |||
MPa (Mega Paskels): 1 MPa = 145 PSI
Note: In the case of a fitting that is a jump size, it is recommend that the lower pressure of the two ends must be recognized as the working pressure rating for that fitting. This is also the case if the fitting has one or more different style ends. For example, straight threads to pipe threads. In this case it is also recommended that the lower pressure rating of the two different style ends must be recognized as the working pressure rating for that fitting.
| Nom SAE Dash Size | Nom Tube O.D. in M.M. | Nom Tube O.D. in Inch | Straight Thread Size | Rigid SAE St. Thread Unions & Bulkhead MPa | Rigid SAE St. Thread Unions & Bulkhead PSI | Adjustable SAE Std. Thread & Female Swivel MPa | Adjustable SAE Std. Thread & Female Swivel PSI |
|---|---|---|---|---|---|---|---|
| 2 | 3.18 | 0.250 | 5/16 24 | 34.5 | 5,000 | 34.5 | 5,000 |
| 3 | 4.76 | 0.188 | 3/8 24 | 34.5 | 5,000 | 34.5 | 5,000 |
| 4 | 6.35 | 0.250 | 7/16 20 | 34.5 | 5,000 | 31.0 | 4,500 |
| 5 | 7.94 | 0.313 | 1/2 20 | 34.5 | 5,000 | 27.5 | 4,000 |
| 6 | 9.52 | 0.375 | 9/16 18 | 34.5 | 5,000 | 27.5 | 4,000 |
| 8 | 12.70 | 0.500 | 3/4 16 | 31.0 | 4,500 | 27.5 | 4,000 |
| 10 | 15.88 | 0.625 | 7/8 14 | 24.0 | 3,500 | 21.0 | 3,000 |
| 12 | 19.05 | 0.750 | 1 1/16 12 | 24.0 | 3,500 | 21.0 | 3,000 |
| 14 | 22.22 | 0.875 | 1 3/16 12 | 21.0 | 3,000 | 17.0 | 2,500 |
| 16 | 25.40 | 1.000 | 1 5/16 12 | 21.0 | 3,000 | 17.0 | 2,500 |
| 20 | 31.75 | 1.250 | 1 5/8 12 | 17.0 | 2,500 | 14.0 | 2,000 |
| 24 | 38.10 | 1.500 | 1 7/8 12 | 14.0 | 2,000 | 10.5 | 1,500 |
| 32 | 50.30 | 2.000 | 2 1/2 12 | 10.5 | 1,500 | 8.0 | 1,125 |
MPa (Mega Paskels): 1 MPa = 145 PSI
Note: In the case of a fitting that is a jump size, it is recommended that the lower pressure of the two ends must be recognized as the working pressure rating for that fitting. This is also the case if the fitting has one or more different style ends. For example, Face Seal to pipe threads. In this case it is also recommended that the lower pressure rating of the two different style ends must be recognized as the wording pressure rating for that fitting.
| Nom SAE Dash Size | Straight Fittings Working MPa | Straight Fittings Working PSI | Straight Fitting Proof MPa | Straight Fitting Proof PSI | Straight Fitting Min.Burst MPa | Straight Fitting Min.Burst PSI | Adjustable Fittings Working MPa | Adjustable Fittings Working PSI | Adjustable Fittings Proof MPa | Adjustable Fittings Proof PSI | Adjustable Fittings Min Burst MPa | Adjustable Fittings Min Burst MPa |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 4 | 41.3 | 6,000 | 82.5 | 12,000 | 165 | 24,000 | 41.3 | 6,000 | 82.5 | 12,000 | 165.0 | 24,000 |
| 6 | 41.3 | 6,000 | 82.5 | 12,000 | 165 | 24,000 | 41.3 | 6,000 | 82.5 | 12,000 | 165.0 | 24,000 |
| 8 | 41.3 | 6,000 | 82.5 | 12,000 | 165 | 24,000 | 41.3 | 6,000 | 82.5 | 12,000 | 165.0 | 24,000 |
| 10 | 41.3 | 6,000 | 82.5 | 12,000 | 165 | 24,000 | 41.3 | 6,000 | 82.5 | 12,000 | 165.0 | 24,000 |
| 12 | 41.3 | 6,000 | 82.5 | 12,000 | 165 | 24,000 | 41.3 | 6,000 | 82.5 | 12,000 | 165.0 | 24,000 |
| 16 | 41.3 | 6,000 | 82.5 | 12,000 | 165 | 24,000 | 34.5 | 5,000 | 69.9 | 10,000 | 138.0 | 20,000 |
| 20 | 27.5 | 4,000 | 55.0 | 8,000 | 110 | 16,000 | 27.5 | 4,000 | 55.0 | 8,000 | 110.0 | 16,000 |
| 24 | 27.5 | 4,000 | 55.0 | 8,000 | 110 | 16,000 | 20.7 | 3,000 | 41.3 | 6,000 | 82.5 | 12,000 |
MPa (Mega Paskels): 1 MPa = 145 PSI
| Nom SAE Dash Size | Code 61 Nominal Flange Size Inch | Maximum recommended Working Pressure MPa | Maximum recommended Working Pressure PSI | Code 62 Nominal Flange Size Inch | Maximum recommended Working Pressure MPa | Maximum recommended Working Pressure PSI | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 8 | 1/2 | 34.5 | 5,000 | 1/2 | 41.4 | 6,000 | ||||||
| 12 | 3/4 | 34.5 | 5,000 | 3/4 | 41.4 | 6,000 | ||||||
| 16 | 1 | 34.5 | 5,000 | 1 | 41.4 | 6,000 | ||||||
| 20 | 1 1/4 | 27.6 | 4,000 | 1 1/4 | 41.4 | 6,000 | ||||||
| 24 | 1 1/2 | 20.7 | 3,000 | 1 1/2 | 41.4 | 6,000 | ||||||
| 32 | 2 | 20.7 | 3,000 | 2 | 41.4 | 6,000 | ||||||
MPa (Mega Paskels): 1 MPa = 145 PSI
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