Model ZSDF7 / ZSXDF7 — Wafer Type · Fire Isolation Valve
Gear Operated
Butterfly Valve
Worm gear actuated wafer butterfly valve for fire sprinkler and standpipe systems. Fits between ANSI 150 / DIN PN16 / GB PN16 flanges — no adapter required. ZSXDF7 model includes DC24V supervisory tamper switch for NFPA 13 / NFPA 72 compliance. DN50–DN300, 1.6 MPa. GGG40 or SS316 body. China fire valve manufacturer, shipped worldwide.
DN50–DN300
1.6 MPa
Worm Gear
Wafer Flanged
GB 5135
NFPA 13
DN50–300Size Range
1.6 MPaWorking Pressure
6.4 MPaStrength Test
DC24VTamper Switch
WaferConnection
Product Variants
Two Models — Signal & Non-Signal
Both use the same wafer body, EPDM seat, and worm gear actuator. The only difference is whether the valve includes a DC24V tamper switch for FACP supervisory wiring.
Signal Version — Supervised
ZSXDF7
- Integrated DC24V 0.5A tamper switch
- Outputs OPEN / TAMPER / CLOSED to FACP
- NFPA 72 Chapter 17 supervisory signal compliance
- Required for electrically supervised fire main isolation per NFPA 13 Section 8.16
- Standard for commercial sprinkler risers, zone control valves, and any valve on a monitored fire alarm system
Non-Signal Version — Unsupervised
ZSDF7
- No tamper switch — lower cost
- Physical lock-open or padlock supervision only
- Suitable for drain valves, test lines, pump test loops
- For valves where AHJ accepts non-electrical supervision
- Same body, seat, and pressure rating as ZSXDF7
Need a grooved-end valve? The Grooved Butterfly Valve (ZSDF8 / ZSXDF8) provides identical performance in a Victaulic-compatible grooved body for fire systems using grooved mechanical couplings. For hazardous (Ex) area applications, see the Explosion Proof Butterfly Valve.
Key Features
Why Specify the ZSDF7 Series
Eight design points that make the ZSDF7 / ZSXDF7 the standard gear-operated wafer butterfly valve for fire protection in commercial, industrial, and high-rise projects.
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Worm Gear Actuator
15:1 to 30:1 mechanical advantage handwheel for low-effort operation at DN100–DN300 under 1.6 MPa system pressure. Self-locking in any position — valve stays put without a locking mechanism.
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Integrated Tamper Switch (ZSXDF7)
DC24V 0.5A two-wire supervisory signal wires directly to any FACP. Detects partial closure within 1–2 handwheel turns and transmits TAMPER alarm to panel. No relay or interface module required.
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Universal Wafer Fit
Installs between ANSI 150, DIN PN16, or GB PN16 flanges without modification. Compact face-to-face (45–80 mm by size) minimizes valve station length on tight riser shafts and mechanical room layouts.
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GGG40 or SS316 Body
Ductile iron GGG40 for standard freshwater and foam systems. Stainless steel SS316 for foam concentrate, seawater, offshore, and coastal installations where corrosion resistance is required.
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EPDM Bi-Directional Seat
Resilient EPDM seat seals at 1.6 MPa in either flow direction. Rated for water, AFFF foam at 3–6% dilution, AR-AFFF, and protein foam-water mixtures. Media temperature range 4–80°C.
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GB 5135 Certified
ZSXDF7 manufactured to GB 5135.13 (signal butterfly valves). ZSDF7 to GB 5135.2 (general fire butterfly valves). Factory hydrostatic test to 6.4 MPa — 4× working pressure. Test certificate included.
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Quarter-Turn Isolation
90° disc travel from full-open to full-closed. Integral position indicator shows open/closed at a glance. Open position marker aligns with pipe bore for quick visual inspection during fire drills and inspections.
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NFPA 13 Compliant
ZSXDF7 tamper switch satisfies NFPA 13 Section 8.16 electrical supervision of water supply control valves. Approved for all major AHJs and insurance underwriters requiring monitored valve position signals.
Technical Data
Full Technical Specifications
Both ZSDF7 and ZSXDF7 share the same wafer body, EPDM seat, 1.6 MPa pressure rating, and DN50–DN300 size range. The tamper switch is the only difference.
| Parameter | ZSXDF7 — With Signal | ZSDF7 — Without Signal |
|---|---|---|
| Model | ZSXDF7-Q-50-300-16 | ZSDF7-Q-50-300-16 |
| Nominal Diameter | DN50 / DN65 / DN80 / DN100 / DN125 / DN150 / DN200 / DN250 / DN300 | |
| Working Pressure | 1.6 MPa (16 bar / 232 psi) | |
| Strength Test Pressure | 6.4 MPa | |
| Seal Test Pressure | 3.2 MPa | |
| Applicable Media | Water · AFFF foam-water · AR-AFFF · Protein foam | |
| Actuator | Worm gear (涡轮蜗杆) handwheel | |
| Tamper Switch | DC24V 0.5A output (OPEN / TAMPER / CLOSED) | None |
| Switch Electrical Rating | DC24V 1.5A rated | — |
| Connection Type | Wafer — between flanges (ANSI 150 / DIN PN16 / GB PN16) | |
| Body Material | Ductile cast iron GGG40 / Stainless steel SS316 | |
| Disc Material | Ductile cast iron / Stainless steel SS316 | |
| Seat Material | EPDM | |
| Stem Material | Stainless steel | |
| Media Temperature | 0–80°C (signal version) | 4–70°C |
| Applicable Standard | GB 5135.13 | GB 5135.2 |
Structural Dimensions
Face-to-Face Length — Wafer Type
Use these face-to-face (F/F) dimensions for valve station layout, pipe spool fabrication, and interference checks. All dimensions in mm. Wafer type is 15–85 mm shorter than the equivalent grooved type per size.
| DN (mm) | 50 | 65 | 80 | 100 | 125 | 150 | 200 | 250 | 300 |
|---|---|---|---|---|---|---|---|---|---|
| F/F (mm) | 45 | 50 | 50 | 55 | 60 | 60 | 65 | 70 | 80 |
Installation note: Wafer butterfly valves require two short flange stub pieces or direct flanged pipe ends on both sides. Ensure flange bolt clearance around the valve actuator — worm gear handwheels on DN200+ may require 120–160 mm radial clearance from pipe centerline. Chain wheel extensions are available for valves installed above 2.5 m.
Applications
Where the ZSDF7 Is Specified
Standard gear-operated wafer butterfly valve for fire main isolation wherever flanged pipe is used. Typical project types:
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Commercial Buildings
Fire main riser isolation valves in office towers, hotels, and shopping centers. ZSXDF7 tamper switch version on all supervised zones per NFPA 13.
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High-Rise Residential
Floor zone control valve (ZCV) assemblies on flanged steel pipe systems. DN80–DN150 on mid-rise; DN150–DN250 on supertall buildings above 150 m.
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Industrial Facilities
Fire water ring main isolation on manufacturing plants, warehouses, and logistics centers. DN150–DN300 on main headers. GGG40 or SS316 per service.
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Pump Stations
Fire pump suction and discharge isolation valves. ZSXDF7 tamper switch provides continuous FACP supervision of pump isolation status per NFPA 20.
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Foam Suppression Systems
Water supply isolation on AFFF and AR-AFFF foam-water systems for tank farms, loading bays, and hangars. EPDM seat rated for full foam service.
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Healthcare & Data Centers
Pre-action and deluge system water supply isolation. ZSXDF7 supervisory wiring integrates into BAS and fire alarm panels for real-time valve status monitoring.
Selection Guide
ZSDF7 vs. ZSXDF7 — Which to Specify
The decision comes down to one question: does the project require electrically supervised valve position monitoring?
Specify ZSXDF7 When:
Signal Version
- Project has a fire alarm control panel (FACP)
- NFPA 13 Section 8.16 electrical supervision is required
- AHJ or insurance underwriter requires monitored valve position
- Valve is on a water supply riser or zone control assembly
- System includes fire pump isolation per NFPA 20
Specify ZSDF7 When:
Non-Signal Version
- Valve is on a drain, test line, or pump test loop only
- AHJ accepts physical lock-open supervision (padlock + chain)
- No fire alarm system present on the project
- Cost reduction is a priority for non-supervised valve locations
- Temporary or construction phase fire protection
Gear vs. Lever? For DN50–DN150 branch line isolations and zone control valves where fast quarter-turn operation is needed, consider the Lever Butterfly Valve (ZSDF7-S / ZSXDF7-S) — same wafer body, same seat, same certifications, quarter-turn handle instead of worm gear.
FAQ
Frequently Asked Questions
Common questions about the ZSDF7 / ZSXDF7 gear operated wafer butterfly valve for fire protection.
What is a gear operated butterfly valve?
A gear operated butterfly valve uses a worm gear mechanism — a handwheel driving a worm screw that rotates the valve disc — instead of a direct lever handle. The worm gear provides 15:1 to 30:1 mechanical advantage, making it practical to operate large DN100–DN300 fire main valves under full 1.6 MPa working pressure with reasonable hand force. In fire protection, gear operated butterfly valves are used on main risers, zone control assemblies, and pump suction/discharge connections where slow, controlled operation prevents water hammer.
What does the tamper switch do in ZSXDF7?
The integrated tamper switch monitors valve disc position continuously. When the valve is fully open, it transmits a "OPEN" supervisory signal to the FACP via a DC24V 2-wire circuit. If the disc is rotated even 1–2 handwheel turns away from full-open — whether for maintenance, testing, or unauthorized closure — the switch changes state and sends a "TAMPER" supervisory alarm to the FACP. This is required by NFPA 72 Chapter 17 for all electrically supervised water supply control valves on systems with monitored fire alarms.
Which FACP brands does the ZSXDF7 tamper switch work with?
The ZSXDF7 outputs a standard DC24V 0.5A two-wire supervisory signal compatible with all major FACP brands including Siemens, Notifier (Honeywell), Hochiki, Edwards EST, Apollo, and Bosch. Connect via standard 2-conductor supervised loop wiring to a supervisory initiating device circuit on the FACP. No adapter, relay, or interface module is required.
How does the wafer butterfly valve install?
The wafer butterfly valve installs between two flanges on the pipe. Insert the valve body between the flange faces with the disc in the closed or partially open position. Thread the flange bolts through both flanges alongside the valve body (not through the valve). Tighten bolts evenly in a star pattern to the appropriate torque for the flange rating. The EPDM seat acts as its own gasket — no additional gaskets are required between the valve and the flanges. After installation, verify the disc opens and closes freely without the flanges restricting disc travel at full open.
GGG40 or SS316 body — which should I specify?
Ductile cast iron GGG40 is the standard selection for onshore fire systems using fresh water or standard AFFF foam. Specify stainless steel SS316 when: (1) the suppression agent is foam concentrate, seawater, or brackish water; (2) installation is coastal, offshore, or in high-humidity environments; (3) the project specification calls for stainless steel per NORSOK S-001 or API standards. Both body materials carry the same 1.6 MPa working pressure rating and GB 5135 certification.
What is the difference between ZSDF7 (wafer) and ZSDF8 (grooved)?
The connection type is the only difference. ZSDF7 installs between standard pipe flanges (wafer design) — compact, cost-effective, requires flanged pipe. ZSDF8 uses Victaulic-compatible grooved mechanical couplings — faster installation (up to 40% less labor), allows angular pipe deflection, preferred for grooved steel pipe fire systems. Both share identical disc, seat, pressure ratings, and optional tamper switch. Specify ZSDF7 for flanged systems; ZSDF8 for grooved systems.
Where is the ZSDF7 manufactured and can I order direct?
The ZSDF7 and ZSXDF7 are manufactured by CA-FIRE (川安消防实业有限公司) at our factory in Nan'an, Quanzhou, China. We supply fire protection contractors, system integrators, and distributors worldwide. Factory-direct orders are accepted for project quantities. Contact sales@ca-fire.com or WhatsApp +86 18150362095 for pricing, lead times, and documentation packages.
Butterfly Valve Family
Other Butterfly Valves in the CA-FIRE Range
All share the same 1.6 MPa rating, EPDM seat, and GB 5135 certification.
