Fire Valves (OS&Y • Butterfly • Ball)
Valves used for isolation, flow control and maintenance safety play a critical role on fire lines: pump rooms, manifolds, risers and branch lines. Depending on project needs, choose OS&Y gate, butterfly or ball types.
Where to Use Which Type?
Quick comparison of the three most common valve types in fire protection piping:
| Type | Application | Advantages | Considerations |
|---|---|---|---|
| OS&Y (Outside Screw & Yoke Gate) | Pump room, manifold, riser heads | Open/close position visible; reliable tightness | Requires height and maintenance space |
| Butterfly | Tight spaces, packaged systems | Compact; wafer/lug mounting | Disk position can affect pressure loss |
| Ball | Drain, by-pass, meter inlet/outlet | Full bore; quick open/close | Typically used in small/medium diameters |
Selection Guide: By Line Function & Size
Choose by line function, diameter (DN), connection type and pressure class (PN).
| Line / Scenario | Recommended Type | Connection | Note |
|---|---|---|---|
| Pump manifold / Riser head | OS&Y | Flanged | Easy position monitoring; service safety |
| Sprinkler distribution / Packaged unit | Butterfly | Wafer / Lug | Compact body for limited space |
| By-pass / Drain / Test line | Ball | Threaded / Flanged | Full bore; fast operation |
Technical Specifications & Standards
Values are typical; they may vary by brand/model and project specification.
| Item | Value / Option | Description |
|---|---|---|
| Body | GG25 cast / GJS ductile | Epoxy coating for corrosion resistance |
| Sealing | EPDM / NBR | Choose by medium and temperature |
| Connection | Flanged • Wafer • Lug • Threaded | Match line size and installation space |
| Nominal Pressure | PN 16 (typical) | Verify against system calculations |
| Standards | TS/EN (by type) | e.g., EN 593 for butterfly; EN 1074 for line valves; project-specific |
Compliance & Documents
Compliance Highlights
- Manufactured in accordance with relevant TS/EN standards
- CE conformity (depending on model)
- Pressure/tightness test records
- English manual and spare parts
Document Note
Certification scope varies by brand/model. Up-to-date documents are provided per specification before order.
Maintenance & Periodic Checks
For reliable operation, we recommend the following checks:
| Interval | Action | Description |
|---|---|---|
| Monthly (visual) | Position, leakage, corrosion | Open/close status, leaks, paint/corrosion check |
| Every 6 months | Functional test | Full open/close; butterfly disc travel, stem and seals |
| Annually | Service & labeling | Tightness, torque setting, update maintenance records |
Frequently Asked Questions
Should I choose OS&Y or butterfly? ▾
Choose butterfly for compact spaces; choose OS&Y on main lines such as risers/manifolds where clear position indication and service safety are priorities.
Is PN 16 sufficient? ▾
PN 16 is typical for most building fire lines; verify against pump curves and static pressures with the designer’s approval.