PN16
Product Overview
The Spirax Sarco SRV2S is a stainless steel direct acting pressure reducing valve with compact design, specifically engineered for steam or gas systems (such as compressed air). All wetted parts are made of 316 stainless steel series materials, providing excellent corrosion resistance and reliability. The product offers three different downstream pressure ranges, distinguished by color-coded markers on the adjustment handwheel. When pressure ranges overlap, using the lower range spring is recommended for better control. This product fully complies with European Pressure Equipment Directive 97/23/EC, can be CE marked as required, and EN10204 3.1 certificates are available (specify when ordering).
Technical Specifications
Pressure/Temperature Limits
| Parameter | Specification |
|---|---|
| Body Design Pressure (PN) | PN25 |
| Maximum Allowable Pressure (PMA) | 25 bar g @ 120°C |
| Maximum Allowable Temperature (TMA) | 212°C @ 19 bar g |
| Minimum Allowable Temperature | -10°C |
| Maximum Operating Pressure with Saturated Steam (PMO) | 19 bar g |
| Maximum Operating Temperature (TMO) | 212°C @ 19 bar g |
| Minimum Operating Temperature | 0°C (consult Spirax Sarco below this temperature) |
| Maximum Downstream Set Pressure | 8.6 bar g |
| Maximum Working Differential Pressure (PMX) | 19 bar |
| Recommended Maximum Turndown (at maximum flow) | 10:1 |
| Design Maximum Cold Hydraulic Test Pressure | 38 bar g |
| Test Pressure Limit After Internal Assembly | Not exceeding 19 bar g |
Downstream Pressure Ranges (Color Coded)
| Color Code | Downstream Control Pressure Range |
|---|---|
| Grey | 0.14 - 1.7 bar g |
| Green | 1.40 - 4.0 bar g |
| Orange | 3.50 - 8.6 bar g |
Sizes and Pipe Connections
| Connection Type | Size Range |
|---|---|
| Threaded (BSP/BS 21 or NPT) | ½", ¾", 1" |
| Flanged (EN 1092 PN25 and ANSI 150) | DN15, DN20, DN25 |
Flow Parameters
| Size | Kvs Value |
|---|---|
| DN15 | 1.5 |
| DN20 | 2.5 |
| DN25 | 3.0 |
Flow Conversion Formulas
- Cv (UK) = Kv × 0.963
- Cv (US) = Kv × 1.156
- Compressed air flow units: dm³/s = l/s (1 l/s ≈ 2 c.f.m.)
Material Specifications
| No. | Component | Material Specification |
|---|---|---|
| 1 | Spring Chamber | Aluminium LM6, Electroless Nickel Plated |
| 2 | Adjustment Handwheel | Plastic (Polypropylene) |
| 3 | Upper Spring Plate | Cast Iron DIN 1691 GG 20, Electroless Nickel Plated |
| 4 | Pressure Adjusting Spring | Silicon Chrome Spring Steel 2803 685 A55 Range 2, Electroless Nickel Plated |
| 5 | Bellows Assembly | Stainless Steel 316T/316L |
| 6 | Bellows Assembly Gasket | Reinforced Graphite Sheet |
| 7 | Spring Chamber Bolt (M8 × 25mm) | Stainless Steel BS 61.5 A 270 / DIN 1.4404 |
| 8 | Body | Stainless Steel BS 3100 316 C12 / ASTM A351 CF 3M, Electropolished |
| 9 | Guide | PTFE Filled Graphite |
| 10 | Pushrod | Stainless Steel ASTM A276 316L |
| 11 | Seat | Stainless Steel BS 3100 316 C12 / ASTM A351 CF3M / DIN 1.4404 |
| 12 | Seat Gasket | Stainless Steel BS 1449 316 S11 |
| 13 | Plug | Stainless Steel 316L |
| 14 | Plug Return Spring | Stainless Steel BS 2056 316 S42 |
| 15 | Strainer | Stainless Steel BS 1446 316 SH |
| 16 | Bottom Cover | Stainless Steel ASTM A276 316L |
| 17 | Bottom Cover 'O' Ring | PTFE |
| 18 | Spring Range Color Marker | Plastic (Polypropylene) |
| 19 | Separator | Stainless Steel BS 1449 316 S13 / AISI 316L |
| 20 | Pin | Copper Plated Mild Steel / DIN 1.4404 |
| 21 | Flange | Stainless Steel BS 3100 316C 12 / ASTM A315 CF3M, Electropolished |
| 22 | Washer | Stainless Steel 316L |
| 23 | Threaded Pushrod | Carbon Steel BS 970 230 M07, Electroless Nickel Plated |
Note
Parts 9, 10, 11, 13, 14, 15 and 19 are components within one assembly.
Dimensions and Weight (Approximate)
Dimensions (Unit: mm)
| Size | Type | A | B | B | C | D* | E1* | E2 | F |
|---|---|---|---|---|---|---|---|---|---|
| ½" | BSP/NPT | 83 | - | - | 62 | 130 | 25 | 15 | - |
| DN15 | PN25 | - | 150 | - | 62 | 130 | 25 | 15 | 97 |
| DN15 | ANSI 150 | - | - | 140 | 62 | 130 | 25 | 15 | 91 |
| ¾" | BSP/NPT | 96 | - | - | 62 | 130 | 25 | 15 | - |
| DN20 | PN25 | - | 150 | - | 62 | 130 | 25 | 15 | 107 |
| DN20 | ANSI 150 | - | - | 140 | 62 | 130 | 25 | 15 | 100 |
| 1" | BSP/NPT | 108 | - | - | 62 | 130 | 25 | 15 | - |
| DN25 | PN25 | - | 160 | - | 62 | 130 | 25 | 15 | 117 |
| DN25 | ANSI 150 | - | - | 153 | 62 | 130 | 25 | 15 | 110 |
Note
E1 and E2 are clearances required for maintenance disassembly.
Weight (Unit: kg)
| Size | Connection Type | Weight |
|---|---|---|
| ½" | Threaded (BSP/NPT) | 1.48 |
| ¾" | Threaded (BSP/NPT) | 1.58 |
| 1" | Threaded (BSP/NPT) | 1.70 |
| DN15 | Flanged (PN25) | 3.1 |
| DN15 | Flanged (ANSI 150) | 2.4 |
| DN20 | Flanged (PN25) | 3.8 |
| DN20 | Flanged (ANSI 150) | 2.8 |
| DN25 | Flanged (PN25) | 4.4 |
| DN25 | Flanged (ANSI 150) | 3.6 |
Selection Guide
How to Use Selection Charts
- The curves marked 2, 3, 4, 5, etc. in the selection chart represent upstream pressure; the vertical line on the left represents downstream pressure;
- Based on actual flow and pressure requirements, find the corresponding intersection point on the chart to determine the appropriate valve size.
Selection Example
If the pressure reducing valve requires a flow rate of 120 kg/h and needs to reduce pressure from 8 bar g to 6 bar g:
- Move horizontally to the right from the 6 bar g downstream pressure scale on the left side of the chart;
- Continue until intersecting with the 8 bar g upstream pressure curve;
- Move vertically downward from the intersection point to determine that a ½" (DN15) SRV2S pressure reducing valve meets this operating condition.
Applicable Media
- Saturated Steam
- Compressed Air
- Other Gas Systems
Installation Instructions
Installation Requirements
- Install the pressure reducing valve on horizontal piping following the flow direction arrow on the valve body;
- For detailed installation steps, refer to the Installation and Maintenance Instructions (IM-P045-10) provided with the product.
Maintenance and Tightening Torques
Recommended Tightening Torques
| No. | Component | Specification | Tightening Torque (N·m) |
|---|---|---|---|
| 7 | Hex Bolt | 13 A/F M8 x 25 | 18 - 24 |
| 11 | Seat | 32 A/F | 108 - 132 |
| 16 | Cover | 32 A/F | 65 - 75 |
Maintenance Precautions
Caution
- Ensure adequate clearance (E1 and E2) is available for maintenance disassembly;
- Consult Spirax Sarco before operating below minimum operating temperature (0°C);
- Test pressure must not exceed 19 bar g after internal assembly installation.
Spare Parts List
Available Spare Parts
| Spare Part Name | Related Part Numbers | Applicable Pressure Range | Remarks |
|---|---|---|---|
| Pressure Adjusting Spring | 4, 18 | 0.14-1.7 bar g (Grey) | Universal for all sizes |
| Pressure Adjusting Spring | 4, 18 | 1.40-4.0 bar g (Green) | Universal for all sizes |
| Pressure Adjusting Spring | 4, 18 | 3.50-8.6 bar g (Orange) | Universal for all sizes |
| Bellows Assembly | 5, 6 | - | Stainless steel material |
| Spring Chamber Bolt | 7 | - | 4 pcs/set, universal for all sizes |
| Plug and Seat Assembly | 6, 11, 12, 15, 19 | - | Universal for all sizes |
| 'O' Ring Kit | 6, 12, 17 | - | Universal for all sizes |
Note
Available spare parts are shown with solid lines; parts shown with dashed lines are not available as spares.
Ordering Information
Product Ordering
Please specify the following information:
- Valve size (e.g., ½", DN15, etc.);
- Connection type (BSP/NPT threaded or PN25/ANSI 150 flanged);
- Pressure range and corresponding color (Grey/Green/Orange);
- Whether EN10204 3.1 certificate is required (specify when ordering).
Ordering Example: ½" BSP SRV2S pressure reducing valve, stainless steel bellows, fitted with orange spring (3.5-8.6 bar g).
Spare Parts Ordering
Please specify the following information:
- Pressure reducing valve model (SRV2S);
- Valve size (e.g., DN15, etc.);
- Spare part name and corresponding pressure range (if applicable).
Ordering Example: Adjusting spring for DN15 Spirax Sarco SRV2S pressure reducing valve, pressure range 3.5-8.6 bar g (Orange).
