D71X Wafer Butterfly Valve
🏭 50 Years Since 1975
✅ CE · API 6D · ISO 9001
🔧 100% Factory Tested
🚚 Fast Global Delivery
• Models: D71X-10 / 10Q / 10C (PN10) and D71X-16 / 16Q / 16C (PN16)
• Body: gray cast iron, ductile iron, or WCB cast steel
• Size: DN40–DN200, wafer face-to-face design
• Seat: Buna-N rubber, 2Cr13 SS stem, ductile iron disc
• Media: steam, water, petroleum, weak acid & alkali up to 135°C
Model: D71X Series | Pressure: PN10 / PN16 | Connection: Wafer | Medium: Water, Steam, Oil, Acid
Gaoshan Valve — D71X Wafer Butterfly Valve
Centerline wafer butterfly valve with rubber-lined disc, available in six body/pressure variants for water, steam, petroleum, and mild chemical service up to 135 °C.
Product Overview
The D71X wafer butterfly valve is a centerline-disc, rubber-seated butterfly valve designed for installation between standard flanges without dedicated lug or lug-less hardware. Six standard variants cover PN10 and PN16 pressure classes with three body material options — gray cast iron (standard), ductile cast iron (intermediate duty), and WCB cast steel (high-pressure service). The Buna-N (NBR) elastomer lining provides reliable bi-directional shutoff against steam, water, petroleum products, weak acids, and alkalis. A compact face-to-face length (L) and a lightweight disc design reduce pipeline load and installation time, making the D71X a cost-effective solution for HVAC, water treatment, industrial process, and fire-protection systems.
As a factory-direct manufacturer since 1975, Gaoshan Valve eliminates distributor markups — you get CE & API certified quality at competitive factory pricing. Bulk order discounts available. Standard sizes are in stock for fast global shipment.
Model Designation Guide
| Model | Nominal Pressure | Body Material | Typical Application |
|---|---|---|---|
| D71X-10 | PN10 | Gray Cast Iron (HT200) | General water & HVAC service |
| D71X-10Q | PN10 | Ductile Cast Iron (QT450) | Slightly elevated mechanical duty, PN10 |
| D71X-10C | PN10 | WCB Cast Steel | Steam, petroleum, mild chemicals, PN10 |
| D71X-16 | PN16 | Gray Cast Iron (HT200) | General water & HVAC service, higher pressure |
| D71X-16Q | PN16 | Ductile Cast Iron (QT450) | Higher-duty service, PN16 |
| D71X-16C | PN16 | WCB Cast Steel | Steam, petroleum, mild chemicals, PN16 |
Key Advantages
Technical Specifications
| Parameter | PN10 Models | PN16 Models |
|---|---|---|
| Nominal Pressure (PN) | 10 bar (1.0 MPa) | 16 bar (1.6 MPa) |
| Shell Test Pressure | 1.5 MPa | 2.4 MPa |
| Seal Test Pressure | 1.1 MPa | 1.8 MPa |
| Working Temperature | ≤ 135 °C | |
| Size Range | DN40 – DN200 | |
| End Connection | Wafer (centerline, between-flange) | |
| Disc Type | Centerline disc | |
| Operation | Manual lever (standard); gearbox or actuator optional | |
| Applicable Medium | Steam, water, petroleum, weak acid, alkali | |
| Design Standard | GB/T 13927 (pressure test); GB/T 12238 (face-to-face) | |
Materials of Main Parts
| Component | D71X-10 / -16 | D71X-10Q / -16Q | D71X-10C / -16C |
|---|---|---|---|
| Body | Gray Cast Iron (HT200) | Ductile Cast Iron (QT450-10) | WCB Cast Steel |
| Seat Ring | Buna-N Rubber (NBR) | ||
| Stem / Worm | 2Cr13 Stainless Steel | ||
| Disc | Ductile Cast Iron (QT450-10) | ||
| Axis Guide / Bushing | Aluminium Bronze | ||
| O-Ring Sealing | Buna-N Rubber (NBR) | ||
Applicable Media
Water
Seawater
Petroleum
Fuel Oil
Weak Acid
Alkali Solutions
HVAC Hot/Chilled Water
Fire Protection Water
Sewage / Wastewater
Principal Dimensions (mm) — PN10 / PN16
| Dim. | DN40 | DN50 | DN65 | DN80 | DN100 | DN125 | DN150 | DN200 |
|---|---|---|---|---|---|---|---|---|
| L | 43 | 43 | 46 | 46 | 52 | 56 | 56 | 60 |
| H | 55 | 58 | 82 | 85 | 105 | 128 | 138 | 175 |
| H0 | 188 | 224 | 235 | 240 | 312 | 350 | 380 | 570 |
| A | 272 | 272 | 272 | 272 | 272 | 272 | 318 | 436 |
| B | 103 | 103 | 103 | 103 | 103 | 103 | 103 | 149 |
L = face-to-face length; H = valve height (lever closed); H0 = total height (lever open); A = lever length; B = valve width (body only). All values in mm. PN10 and PN16 share identical face-to-face dimensions.
Selection Guide: Wafer vs. Lug vs. Double-Flanged
| Feature | D71X (Wafer) | Lug Type | Double-Flanged |
|---|---|---|---|
| Dead-end service | ✗ No | ✓ Yes | ✓ Yes |
| Installation cost | Lowest | Medium | Highest |
| Weight / pipe load | Lightest | Medium | Heaviest |
| Pipe removal without valve removal | ✗ No | ✓ Yes | ✗ No |
| Typical use | Through-line service | End-of-line / isolation | High pressure / large bore |
Product Structure Diagram
Quality Assurance & Testing
Every D71X butterfly valve undergoes the following factory acceptance tests before shipment:
- Shell Pressure Test — hydrostatic test at 1.5×PN to verify body integrity.
- Seat Leakage Test — air or water test at rated pressure; zero seat leakage required per GB/T 13927 Class VI.
- Stem Torque Verification — full open/close cycle under differential pressure to confirm lever and stem adequacy.
- Dimensional Inspection — face-to-face, flange bolt-circle, and bore dimensions checked against GB/T 12238.
- Visual & NDT — casting surfaces inspected; critical welds (cast steel models) subject to dye-penetrant examination.
Installation & Maintenance Notes
- Orientation: D71X valves can be installed in any pipe orientation (horizontal, vertical, or inclined). Confirm the lever has adequate swing clearance before finalising position.
- Flange bolts: Use through-bolts to clamp both pipe flanges together through the wafer body. Tighten in a cross pattern to avoid rubber seat distortion.
- Flow direction: No flow-direction restriction for full on/off service. For throttling applications, confirm acceptable disc stability with our applications team.
- Rubber seat inspection: Inspect the NBR seat annually or after prolonged steam service. Replace if cracking, swelling, or permanent deformation is observed.
- Stem packing: The stem uses O-ring sealing; no packing adjustment is required. Replace O-rings if stem leakage is detected during service.
- Actuator upgrade: The ISO 5211 top pad accepts standard pneumatic or electric actuators. Consult Gaoshan Valve for actuator sizing and bracket selection.
Why Buy D71X from Gaoshan Valve?
- 50-Year Factory — Manufacturing industrial valves since 1975, 400+ employees, 120,000 m² facility
- Certified Quality — CE (EU PED), API 6D, ISO 9001/14001/45001 certified
- Trusted by Giants — Approved supplier to Sinopec, CNPC, and projects in 20+ countries
- Factory-Direct Pricing — No middlemen, no distributor markup. You pay the factory price
- 100% Tested — Every valve undergoes shell test + seat leakage test before shipment
- Fast Delivery — Standard sizes DN40–DN200 in stock, ready to ship worldwide
Frequently Asked Questions
Q: What is the minimum order quantity (MOQ)?
No strict MOQ. Trial orders from 1 piece accepted for standard sizes (DN40–DN200). Bulk pricing from 50+ units.
Q: How long does delivery take?
Standard cast iron and ductile iron sizes in stock — ship within 3–7 working days. WCB cast steel and custom configurations: 15–25 working days. Worldwide shipping via sea and air freight.
Q: Do you provide inspection reports and certifications?
Yes. Every shipment includes factory inspection report with shell and seat leakage test results. CE, API 6D, ISO 9001 certificates available. Third-party inspection (SGS, BV, TÜV) can be arranged.
Q: What payment terms do you accept?
T/T (30% deposit, 70% before shipment) and L/C at sight. For trial orders: Western Union and PayPal accepted.
Q: Can you customize flange drilling to ANSI or DIN?
Yes. Standard is GB/T 17241. ANSI B16.5 Class 150, DIN EN 1092, and JIS drilling available on request at no extra cost for bulk orders.
Ordering Information
| Item | Specify When Ordering |
|---|---|
| Model | D71X-10 / 10Q / 10C / 16 / 16Q / 16C |
| Nominal Size | DN40 / DN50 / DN65 / DN80 / DN100 / DN125 / DN150 / DN200 |
| Flange Drilling Standard | GB/T 17241 (standard); ANSI / DIN on request |
| Operation Type | Manual lever (standard); gearbox; pneumatic or electric actuator |
| Seat Material | NBR (standard); EPDM / PTFE-lined on request |
| Disc Coating | Standard ductile iron; nickel-plated or SS disc on request |
Related Butterfly Valves
Request a Quote or Technical Support
Gaoshan Valve supplies D71X wafer butterfly valves with certified inspection reports. Fast delivery for standard sizes; custom sizes and actuated assemblies available on request. Contact our team for pricing, technical datasheets, and application guidance.