VLV-ST · ST-4 Manual Diaphragm Valve
Manual spring-type diaphragm packless valve — GasFlo ST-4 Series, the manually operated version of the HPST-4. Body in brass, nickel-plated brass or 316L stainless steel; 316L SST wetted diaphragm. Max 3,500 PSIG, Cv 0.26. FNPT and MNPT connections are available on a forged body only.
- Max working pressure
- 3,500 PSIG
- Flow coefficient
- Cv = 0.26
- Seat orifice
- Ø.125"
- Seat material
- PCTFE (standard), Polyimide (optional)
Materials
| Max working pressure | 3,500 PSIG |
|---|---|
| Flow coefficient | Cv = 0.26 |
| Seat orifice | Ø.125" |
| Seat material | PCTFE (standard), Polyimide (optional) |
| Diaphragm material | 316L SST |
| Temperature range | −65°F to +150°F (PCTFE) / −65°F to +250°F (Polyimide) |
| Seat leakage (max) | 2×10⁻⁸ ATM CC/SEC He |
| Inboard leakage (max) | 2×10⁻⁸ ATM CC/SEC He |
| Bottom mount | 2 × 10-32 tapped holes on a 1" bolt circle |
| Panel mount | Panel hole size 49/64" |
| Repair kit | RK-77102 |
Applications & Documents
Configure your order
Select the variables exactly as they appear in the manufacturer datasheet. The full part number is assembled automatically.
Inlet port size
single select · 2 valuesInlet connection
single select · 6 values* F and M (pipe thread) connections: available on forged body only
Outlet port size
single select · 2 valuesOutlet connection
single select · 6 values* F and M (pipe thread) connections: available on forged body only
Material
single select · 3 valuesOptional features
single select · 3 valuesSelect variables
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