Pressure Loss in Fittings and Valves Expressed as Equivalent Length of Tube
| Nominal or standard size, inches | Fittings | Valves | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Standard Ell | 90° Tee | Coupling | Ball | Gate | Btfly | Check | |||
| 90° | 45° | Side branch |
Straight run | ||||||
| 3/8 | .5 | – | 1.5 | – | – | – | – | – | 1.5 |
| ½ | 1 | .5 | 2 | – | – | – | – | – | 2 |
| 5/8 | 1.5 | .5 | 2 | – | – | – | – | – | 2.5 |
| ¾ | 2 | .5 | 3 | – | – | – | – | – | 3 |
| 1 | 2.5 | 1 | 4.5 | – | – | .5 | – | – | 4.5 |
| 1¼ | 3 | 1 | 5.5 | .5 | .5 | .5 | – | – | 5.5 |
| 1½ | 4 | 1.5 | 7 | .5 | .5 | .5 | – | – | 6.5 |
| 2 | 5.5 | 2 | 9 | .5 | .5 | .5 | .5 | 7.5 | 9 |
| 2½ | 7 | 2.5 | 12 | .5 | .5 | – | 1 | 10 | 11.5 |
| 3 | 9 | 3.5 | 15 | 1 | 1 | – | 1.5 | 15.5 | 14.5 |
| 3½ | 9 | 3.5 | 14 | 1 | 1 | – | 2 | – | 12.5 |
| 4 | 12.5 | 5 | 21 | 1 | 1 | – | 2 | 16 | 18.5 |
| 5 | 16 | 6 | 27 | 1.5 | 1.5 | – | 3 | 11.5 | 23.5 |
| 6 | 19 | 7 | 34 | 2 | 2 | – | 3.5 | 13.5 | 26.5 |
| 8 | 29 | 11 | 50 | 3 | 3 | – | 5 | 12.5 | 39 |
NOTES: Allowances are for streamlined soldered fittings and recessed threaded fittings.
For threaded fittings, double the allowances shown in the table.
The equivalent lengths presented above are based upon a C factor of 150 in the Hazen-Williams friction loss formula. The lengths shown are rounded to the nearest half foot.
For threaded fittings, double the allowances shown in the table.
The equivalent lengths presented above are based upon a C factor of 150 in the Hazen-Williams friction loss formula. The lengths shown are rounded to the nearest half foot.