Bleeder Screw Gauge Valve Series : NVD31
Features / Benefits :
- Low operating torque, Anti blow-out stem.
- Stem threads are cold rolled for smooth operation.
- Choice of optional stem to provide greater flexibility.
- Choice of packing PTFE or Graphite.
- Stem packing below the threads, protects the Stem threads from system media.
- Orifice size : 4.3mm, 6.3mm and 9.5mm, Flow Coefficient (Cv) from 0.37 to 1.8.
- Available in Material SS316, all wetted parts in accordance with NACE MR01-75.
- Every Valve is pressure tested.
Product Range & Operating Parameters :
- Pressure Rating : UPTO 6000 PSIG (413 Bar) at CWP.
- Temperature Rating :
- : -54° C to 232° C with PTFE Packing.
- : -96° C to 426° C with Graphite Packing.
- End Connections –
- Fractional : 1/4″ to 1″ Tube OD.
- Metric : 6mm to 16mm Tube OD.
- Pipe Threads : 1/4″ to 3/4″ Male / Female NPT, BSPT, BSP & Socket Weld
Applications :
- General Plant Services
- Hydraulic & Pneumatic
- Instrumentation Isolation,
- Pressure Measurement Devices
Stem Type :
SD GREEN PVT LTD Valves are available with choice of optional stem to provide greater flexibility.
Non-Rotating (NR) : It is standard self-centering non-rotating stem tip typically used in high cycle application to extend the Valves life.
‘V’ Stem (VS) : It is used for general purpose liquid and gases.
Soft Seat (SF) : A soft seat stem requires a lower sealing torque. It is replaceable and suitable for temperature UPTO 120o C.
Regulating Stem (RS) : It is used where some degree of flow control required.
Technical Data :
The temperature and pressure rating for a standard Valve with PTFE packing.
| Temperature | Pressure | |
| PSIG | Bar | |
| -54oC to 38oC | 6000 | 413 |
| -54oC to 93oC | 5160 | 351 |
| -54oC to 148oC | 4660 | 317 |
| -54oC to 204oC | 4280 | 291 |
| -54oC to 232oC | 4130 | 289 |
Type Test Approvals :
The design of SD GREEN PVT LTD Bleeder Screw Gauge Valves Series : NVD31 have been tested to Hydrostatic Proof & Burst Test in accordance to MSS SP-99-2016a Clause 5.5 & 5.6.
Testing :
- Standard Test – Each Valve is pressure tested with Nitrogen at 2000 PSIG (138 Bar) for leakage at the seat and packing.
- Optional Hydrostatic Test – This Test is performed with De-ionized water at 1.5 times the working pressure.
Certification :
The Certificate to 3.1 acc. to EN10204 for Valves body material and pressure test will be provided on request.
Material of Constructions :
| Sr. No. | Part Description | Material |
| 1 | Handle | SS316 |
| 2 | Screw | SS316 |
| 3 | Valve Stem | SS316 |
| 4 | Dust Cap | PVC |
| 5 | Packing Adjustment Screw | SS316 |
| 6 | Lock Nut | SS316 |
| 7 | Bonnet | SS316 |
| 8 | Washer | SS316 |
| 9 | Packing | PTFE / Graphite |
| 10 | Safety Pin | SS316 |
| 11 | Valve Body | SS316 |
| 12 | Drain Plug | SS316 |
Standard Configuration Dimensions :
| End Connection | Flow Data | Dimensions In mm | SD GREEN PVT LTD Part No. | |||||
| Type | Size – A | Orifice(mm) | Cv | B | E | F | A/F | |
| Female to Female NPT | 1/4″ | 4.3 | 0.37 | 66.0 | 80.0 | 54.0 | 28.57 | NVD31-FF4N |
| 3/8” | 4.3 | 0.37 | 66.0 | 80.0 | 54.0 | 28.57 | NVD31-FF6N | |
| 1/2″ | 4.3 | 0.37 | 69.0 | 84.0 | 58.0 | 31.75 | NVD31-FF8N | |
| Male to Female NPT | 1/4″ | 4.3 | 0.37 | 73.0 | 80.0 | 54.0 | 28.57 | NVD31-MF4N |
| 3/8” | 4.3 | 0.37 | 73.0 | 80.0 | 54.0 | 28.57 | NVD31-MF6N | |
| 1/2″ | 4.3 | 0.37 | 85.0 | 84.0 | 58.0 | 31.75 | NVD31-MF8N | |
| Female to Female BSP | 1/4″ | 4.3 | 0.37 | 69.0 | 80.0 | 54.0 | 28.57 | NVD31-FF4RG |
| 3/8” | 4.3 | 0.37 | 69.0 | 80.0 | 54.0 | 28.57 | NVD31-FF6RG | |
| 1/2″ | 4.3 | 0.37 | 88.0 | 84.0 | 58.0 | 31.75 | NVD31-FF8RG | |
| Male to Female BSP | 1/4″ | 4.3 | 0.37 | 69.0 | 80.0 | 54.0 | 28.57 | NVD31-MF4G |
| 3/8” | 4.3 | 0.37 | 69.0 | 80.0 | 54.0 | 28.57 | NVD31-MF6G | |
| 1/2″ | 4.3 | 0.37 | 88.0 | 84.0 | 58.0 | 31.75 | NVD31-MF8G | |
Dimensions are for reference only and are subject to change.