Description
Spirax Sarco BRV71 and BRV73 ductile iron direct-acting pressure reducing valves are designed for steam systems. BRV71 features threaded connections, while BRV73 features flanged connections. Three downstream pressure ranges are available, identified by different-colored indicator plates. Multiple sizes and pipe connection options are available, with corresponding pressure and temperature limits. The product documentation also includes material specifications, sizing methods for saturated steam and compressed air, Kv values, weights, safety information, installation and maintenance instructions, ordering information, and spare parts details.
Available Models
| Model | SKU |
|---|---|
| 1” BRV71 GREY | 2103000 |
| 1” BRV71 GREEN | 2103100 |
| 1” BRV71 ORG | 2103200 |
| 1 1/4” BRV71 GREY | 2103300 |
| 1 1/4” BRV71 GREEN | 2103400 |
| 1 1/4” BRV71 ORG | 2103500 |
| 1 1/2” BRV71 GREY | 2103600 |
| 1 1/2” BRV71 GREEN | 2103700 |
| 1 1/2” BRV71 ORG | 2103800 |
| 2” BRV71 GREY | 2103900 |
| 2” BRV71 GREEN | 2104000 |
| 2” BRV71 ORG | 2104100 |
| DN25 BRV73 GREY | 2103093 |
| DN25 BRV73 GREEN | 2103193 |
| DN25 BRV73 ORG | 2103293 |
| DN32 BRV73 GREY | 2103393 |
| DN32 BRV73 GREEN | 2103493 |
| DN32 BRV73 ORG | 2103593 |
| DN40 BRV73 GREY | 2103693 |
| DN40 BRV73 GREEN | 2103793 |
| DN40 BRV73 ORG | 2103893 |
| DN50 BRV73 GREY | 2103993 |
| DN50 BRV73 GREEN | 2104093 |
| DN50 BRV73 ORG | 2104193 |
Downstream Pressure Ranges
| Color | Downstream Control Pressure Range |
|---|---|
| Grey | 0.14 - 1.7 bar g |
| Green | 1.40 - 4.0 bar g |
| Orange | 3.50 - 9.0 bar g |
Note: When pressure ranges overlap, the spring from the lower range provides better control.
Sizes and Pipe Connections
-
DN25, 32, 40 & 50 flanged connections: PN16, JIS10, ANSI 150.
-
1”, 1¼”, 1½” and 2” threaded connections: BSP and NPT.
Pressure/Temperature Limits
| Valve Design Conditions | PN16 |
|---|---|
| PMA maximum allowable pressure | 16 bar g @ 120 °C |
| TMA maximum allowable temperature | 184 °C @ 10 bar g |
| Minimum allowable temperature | -10 °C |
| PMO maximum operating pressure with saturated steam | 10 bar g |
| TMO maximum operating temperature | 184 °C @ 10 bar g |
| Minimum operating temperature (Note: consult Spirax Sarco below this temperature) | 0 °C |
| Maximum downstream set pressure | 9 bar g |
| PMX maximum operating differential pressure | 10 bar |
| Recommended maximum pressure reduction ratio (at maximum flow) | 10 : 1 |
| Designed maximum cold hydraulic test pressure | 24 bar g |
| Note: After internal components are installed, test pressure must not exceed | 16 bar g |
Materials
| No. | Component | Material |
|---|---|---|
| 1 | Valve body | Ductile iron DIN 1693 GGG 40.3 ELNP coating |
| 2 | Pressure-adjusting spring | Silicon-chromium alloy BS 2803 685 A55 |
| 3 | Adjusting screw | Carbon steel BS 970 230 M07 |
| 4 | Plain washer | Stainless steel Gr.18/10/3-4A |
| 5 | Adjusting handle | Nylon 10B 140 |
| 6 | Pin | Stainless steel AISI 420 |
| 7 | Spring plate | Cast iron DIN 1691 GG 20 |
| 8 | Spring chamber | Aluminum 2ELNP coated |
| 9 | Upper gasket | Semi-rigid laminated graphite |
| 10 | Lower gasket | Semi-rigid laminated graphite |
| 11 | Bellows assembly | Stainless steel 316L |
| 12 | Bellows/pushrod assembly | Stainless steel 316L with 15% graphite fill |
| 13 | Indicator plate | Polypropylene |
| 15 | Locking pin | Brass |
| 16 | Valve plug (including seal 27) | Stainless steel BS 970 431 S29 |
| 17 | Strainer screen | Stainless steel 316L |
| 18 | Lower pushrod | Stainless steel BS 970 431 S29 |
| 19 | Bottom cover | Ductile iron DIN 1693 GGG 40.3 ELNP coating |
| 20 | Bolt | Zinc-plated steel BS 3692 Gr. 8.8 |
| 21 | Bolt | Zinc-plated steel BS 3692 Gr. 8.8 |
| 22 | Washer | Stainless steel BS 1449 304 515 |
| 23 | Guide bush | PTFE with 15% graphite fill |
| 24 | Return spring | Stainless steel BS 2056 316 S42 |
| 25 | PTFE washer | Virgin PTFE BS 6564 Type 2 Gr. B |
| 26 | ‘O’ ring seal | EPDM E 0962-90 |
| 27 | Valve plug ‘O’ ring seal | EDPM E 0962-90 |
Kv Values
| 1” - DN25 | 1¼”- DN32 | 1½”- DN40 | 2” - DN50 |
|---|---|---|---|
| 9.3 | 11.1 | 15.7 | 16.2 |
Conversion formulas: Cvv (UK) = Kv x 0.963; Cv (US) = Kv x 1.156
Weight (Approximate)
| Size | Threaded (kg) | Flanged (kg) |
|---|---|---|
| DN25 - 1” | 4.40 | 5.90 |
| DN32 - 1¼” | 4.20 | 7.65 |
| DN40 - 1½” | 4.95 | 8.55 |
| DN50 - 2” | 4.75 | 9.40 |
Note: Flanged weights are for BRV73 PN16 models.
Safety Information, Installation and Maintenance
For detailed information, refer to the installation and maintenance guide supplied with the product (IM-P045-10).
Installation instructions: Install the pressure reducing valve in a horizontal pipeline, with flow in the direction indicated by the arrow on the valve body.
Ordering Information
Example: 1 - Spirax Sarco BRV71 pressure reducing valve with stainless steel bellows, fitted with an orange 1” spring (3.5 - 9.0 bar g).