Block-and-bleed valve
2-valve manifold
Model
NV2
Applications
● Shut off and vent pressure measuring instruments
● For gaseous and liquid aggressive media that are not highly viscous or crystallising, also in aggressive environments
● Process industry: oil and gas, chemical and petrochemical industries, power generation, water and wastewater
Special features
● Low-wear design due to non-rotating spindle tip in the bonnet
● Low torque and smooth operation of valve handle even at high pressure
● Enhanced safety due to blow-out proof bonnet design
● Valve seat tested for leak tightness per ISO 5208 leak rate A
● Customer-specific combination of valves and instruments (instrument hook-up) on request
Model Overview
Specification
Basic features | ■ Blow-out proof valve spindle ■ Non-rotating, low-wear spindle tip ■ Metal-to-metal back seat design | |
Special design features | ■ Without ■ For oxygen, oil- and grease-free ■ ASME B31.1, power piping (only available with graphite sealing packing) | |
Valve body | ■ Square design ■ Flat design ■ H-shaped design ■ T-shaped design | |
Standards used | Basic design ■ MSS SP-99, valves for measuring instruments ■ MSS SP-105, instrument valves for code applications ■ ASME B16.34, valves – flanged, threaded and welding end ■ ASME B1.20.1, pipe threads, general purpose (inch) ■ ASME B31.3, process piping ■ ASME BPVC, section VIII, division 1
Special design ■ Without ■ ISO 10497, API 6FA and API 607, type test for fire safety ■ TA-Luft (VDI 2440) and ISO 15848-1, type test for fugitive emissions
Tests MSS SP-61, pressure testing of valves
Special tests ■ Without ■ API 598, valve inspection and testing ■ ISO 5208, pressure testing of metallic valves with leakage rate A
Material requirements NACE MR0175 / ISO 15156, use in H₂S-containing environments in oil and gas production
Special material requirements ■ Without ■ NORSOK M-630, specification for use in pipelines (Norway)
Marking MSS SP-25, standard marking system for valves | |
Mounting | ■ Without mounting holes ■ Suitable for mounting bracket, with mounting holes | |
Bonnet | Bonnet position ■ In-line ■ Angled ■ Vent angled under 45° ■ Side-by-side ■ L-shaped
Bonnet design ■ Screwed bonnet, 4 mm [0.16 in] bore size ■ Bonnet with extended handle, 4 mm [0.16 in] bore size ■ Miniature bonnet, 4 mm [0.16 in] bore size ■ Cryogenic bonnet for medium temperatures to -196 °C [-320 °F], 4 mm [0.16 in] bore size ■ OS&Y bonnet, bolted, 8 mm [0.31 in] bore size ■ Bolted bonnet, 8 mm [0.31 in] bore size
Bonnet variant ■ Without ■ Anti-tamper for shut-off and vent valve, padlock not included ■ Anti-tamper for shut-off and vent valve, padlock included ■ Anti-tamper for vent valve, padlock not included ■ Anti-tamper for vent valve, padlock included ■ Small T-handle ■ T-handle from stainless steel 316L (1.4404) | |
Process connection / Instrument connection | Standard ■ Threaded connection per ANSI B1.20.1, code NPT ■ Threaded connection per ISO 228-1, code G ■ Swivel connection ■ Weld-in connection ■ Compression fitting ■ Flange connection per IEC 61518, Form A or Form B ■ Connection for EMICO gauge
Size ■ ¼ NPT ■ ⅜ NPT ■ ½ NPT ■ ¾ NPT
■ G ¼ ■ G ⅜ ■ G ½ ■ G ¾
Vent connection ■ ¼ NPT female, plug screw included ■ ½ NPT female, plug screw included ■ ¼ NPT female with installed bleeder screw ■ G ¼ female, plug screw included ■ G ½ female, plug screw included ■ 2 x ¼ NPT female, plug screw included and bleeder screw installed | |
Operating conditions | Permissible operating pressure ■ ≤ 3,000 psi or ≤ 206 bar ■ ≤ 6,000 psi or ≤ 420 bar ■ ≤ 10,000 psi or ≤ 690 bar
Pressure and temperature limits The limits for operating pressure and temperature depend on the version and the sealing material. | |
| Material | Wetted parts Valve body, bonnet body ■ Stainless steel 316/316L (1.4401/1.4404) ■ Stainless steel 321 (1.4541) ■ Monel 400 (2.4360) ■ Hastelloy C276 (2.4819)
Spindle tip ■ Stainless steel 316/316L (1.4401/1.4404) ■ Monel 400 (2.4360) ■ Hastelloy C276 (2.4819)
Sealing packing ■ PTFE, temperature range: -55 ... +204 °C [-67 ... +400 °F] ■ Polar PTFE, temperature range: -70 ... +204 °C [-94 ... +400 °F] ■ Graphite, temperature range: -55 ... +500 °C [-67 ... +932 °F] ■ SIGRAFLEX® ZX graphite, nuclear quality, temperature range: -55 ... +500 °C [-67 ... +932 °F] ■ FKM, temperature range: -29 ... +180 °C [-20 ... +356 °F] ■ FKM AED, temperature range: -46 ... +180 °C [-50 ... +356 °F] ■ RTFE , temperature range: -55 ... +180 °C [-67 ... +356 °F]
Non-wetted parts Gland nut, valve spindle, seal bush, locking nut, locking pin
Handle ■ Stainless steel 304 ■ Stainless steel 316/316L (1.4401/1.4404) | |
Bonnet design
Screwed bonnet
Pressure-temperature diagram
The table above provides information about the characteristics of the sealing packing at the respective process parameters.
To maximise the service life, it is recommended that the valve should not be operated continuously at the temperature limits.
The minimum design temperature for most needle valves is -55 °C [-67 °F]. Some versions have other design temperatures due to material specifications.
For continuously low operating temperatures ≤ -55 °C [≤ -67 °F] a special polar design is needed.
Dimensions in mm [in]
The following dimensions are for versions made of stainless steel 316/316L (1.4401/1.4404). With other materials the dimensions and shape may change.
Model NV201, square design, 90° angled bonnet position, in-line connections
Model NV202, square design, in-line bonnet position, in-line connections
Model NV211, flat design, angled bonnet position, in-line connections
Model NV212, flat design, in-line bonnet position, in-line connections
Model NV213, flat design, side-by-side bonnet position, in-line connections
Model NV217, flat design, L-shaped bonnet position, in-line connections
Model NV222, square design, in-line bonnet position, double connection for pressure outlet
Model NV291, flat design, angled bonnet position, angled connections
Model NV2C1, flat design, angled bonnet position, integral flange mounting
Model NV2F2, flat design, in-line bonnet position, direct flange mounting
Model NV2F7, flat design, L-shaped bonnet position, direct flange mounting
Model NV2F8, flat design, vent bonnet position under 45°, direct flange mounting
Model NV2H1, H-shaped design, angled bonnet position, direct flange mounting
Model NV2T1, T-shaped design, angled bonnet position, direct flange mounting
Ordering information Model / Bonnet design / Bonnet variant / Sealing packing / Special design features / Options
