Spirax Sarco SRV461 and SRV463 stainless steel direct-acting pressure reducing valves have all wetted parts manufactured from AISI 316L/1.4404, 1.4408, and 1.4462 stainless steel. They are suitable for steam, liquids, and gases. Typical applications include clean steam, gases, and liquids for centrifuges, freeze dryers, sterilizers, autoclaves, process vessels, humidifiers, and kitchen equipment.

MPN	Description
1862463	SRV463 DN25 PN40 0.02 - 0.12 BARG
1862793	SRV463 DN25 PN40 0.8 - 2.5 BARG
1862863	SRV463 DN25 PN40 2 - 5 BARG
1862963	SRV463 DN25 PN40 4 - 8 BARG
1863063	SRV463 DN25 PN40 6 - 12 BARG

Sizes and Pipe Connections

SRV461	½”, ¾”, 1”, 1¼”, 1½” and 2” BSP threaded
SRV463	DN15, DN20, DN25, DN32, DN40 and DN50 EN 1092 PN40 flanges
*For other connections, consult Spirax Sarco.

Pressure/Temperature Limits

Valve body design conditions	PN40
Maximum design pressure	38 bar g @ 38 °C
Maximum design temperature	300 °C @ 23.2 bar g
Minimum design temperature	-10 °C
Maximum operating temperature, steam	190 °C @ 10.9 bar g
Liquids and gases	130 °C @ 30 bar g
Minimum operating temperature Note: consult Spirax Sarco below this temperature	-10 °C
Maximum differential pressure	Refer to the allowable pressure reduction ratio table
Maximum cold hydraulic test pressure	60 bar g

Allowable Pressure Reduction Ratio (Maximum P1 / P2)

Set range (bar g)	Nominal size
G½” - 1” DN15 - DN25	G1¼” - 2” DN32 - DN50
0.02 - 0.12	80:1	50:1
0.10 - 0.50	40:1	25:1
0.30 - 1.10	30:1	18:1
0.80 - 12.00	20:1	12:1

Materials

Item No. Component	Material	Werkstoff No.	Corresponding AISI specification
1 Valve body	Stainless steel	1.4404	316L
2 Spring chamber	Stainless steel	1.4404	316L
3 Bonnet	Stainless steel	1.4571	316Ti
4 Valve seat	Stainless steel	1.4404	316L
5 Valve plug	Stainless steel	1.4404	316L
6 Diaphragm	EPDM
7 O-ring	EPDM
8 O-ring	EPDM
9 O-ring	EPDM
10 Piston	Stainless steel	1.4571	316Ti
11 Upper spring support	Stainless steel	1.4571	316Ti
12 Spring	Stainless steel	1.4310	301*
13 Adjusting screw	Stainless steel	1.4404	316L
14 Locking ring	Stainless steel	AISI 300 series
15 Flange	Stainless steel	1.4404	316L
16 Soft seal	FEPM
17 Spring clip	Stainless steel	1.4301	304
Not directly equivalent; the closest AISI specification is shown. For hydrocarbon applications, a valve plug and diaphragm with FPM soft seals can be selected.

Weight (Approximate) kg

1/2”-1”	13.5	7.1	6.1	3.1	3.1
DN15 - DN25 (flanged)	15.3	8.9	7.9	4.9	4.9
11/4-2”	14.4	8.0	7.0	4.0	4.0
DN32 - DN50 (flanged)	18.4	12.0	11.0	8.0	8.0

Kv Values

Size	1/2”	3/4”	1”	11/4” DN32	11/2” DN40	2”
Kv value at 20% deviation	4.0	5.6	6.4	17.6	17.6	17.6
Maximum Kv	5.0	7.0	8.0	22.0	22.0	22.0
For valve sizing to ensure maximum control accuracy, especially with large load changes, use the Kv value at 20% deviation. Use the maximum Kv value when sizing a safety valve. Leakage ≤0.05% of maximum medium value.

Recommended Fluid Velocities

Steam	10-40m/s	15-60 m/s
Gas	Up to 2bar: 2 - 10 m/s; above 2barg: 5-40m/s
Liquid	1-5m/s

Safety Information, Installation, and Maintenance

Detailed installation and maintenance instructions (IM-P186-02) are supplied with the product.

Note: When used with steam, the spring chamber must be located below the pipeline. A downstream pressure-sensing line is also required.

Ordering Information

Example: 1-BSP Spirax Sarco SRV461 pressure reducing valve, ½”, pressure range 0.8-2.5 bar.