Spirax Sarco BRV71 and BRV73 ductile iron direct-acting pressure reducing valves are designed for steam systems. BRV71 has threaded connections, while BRV73 has flanged connections. Three downstream pressure ranges are available, identified by different colors of the indicator plate (13). Multiple sizes and pipe connection options are available, with applicable pressure/temperature limits. The product includes components made from various materials, selection methods for saturated steam and compressed air, Kv values, weight information, safety, installation and maintenance instructions, ordering information, and spare parts information.

Available Models

Model	SKU
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 lower-range spring provides better control.

Size 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 for 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
Maximum Designed Cold Hydraulic Test Pressure	24 bar g
Note: After internal components are installed, test pressure must not exceed	16 bar g

Materials

Item	Component	Material
1	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	Flat 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, 15% graphite-filled
13	Indicator plate	Polypropylene
15	Locking pin	Brass
16	Valve plug (including seal 27)	Stainless steel BS 970 431 S29
17	Strainer	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, 15% graphite-filled
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 Instructions supplied with the product (IM-P045-10).

Installation instructions: Install the pressure reducing valve in a horizontal pipeline, following the flow 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).