The cartridge-style seat is a replaceable sealing assembly retained by a metal backup ring. The metal ring gives the elastomer or polymer seat positive radial support and prevents seat extrusion under differential pressure. When the seat reaches the end of its service life, the cartridge can be removed and replaced while the valve body remains in the pipeline.
| Item | Technical Benefit |
|---|---|
| Lugged body | Independent flange bolting permits end-of-line service and downstream pipe removal without upstream shutdown. |
| Cartridge-style seat | Replaceable sealing assembly reduces repair time and material cost; valve body does not need to be removed from the line. |
| Metal backup ring | Provides positive seat retention and prevents seat extrusion at full rated pressure and under vacuum. |
| Double-shaft disc | Upper and lower shaft support improves disc concentricity, torque transfer, and long-term alignment. |
| Blowout-proof shaft | Machined shaft shoulder prevents stem ejection under pressure, meeting API 609 anti-blowout requirements. |
| ISO 5211 top flange | Direct mounting of manual gear operators, pneumatic actuators, and electric actuators. |
| Bidirectional bubble-tight seat | Zero visible leakage in both flow directions when tested to EN 12266-1 Rate A / API 598. |
| Parameter | Specification |
|---|---|
| Nominal Diameter | DN200 / 8 inch |
| Body Style | Lugged, threaded inserts |
| Pressure Rating | PN10 / PN16 / ANSI Class 125-150 |
| Face-to-Face | API 609 Category A / EN 558 Series 20 short pattern |
| Flange Drilling | EN 1092-2 / ANSI B16.5 Class 150 / ASME B16.42 Class 150 |
| Top Flange | ISO 5211 F10 / F12 depending on operator selection |
| Seat Test | 1.1 times rated pressure, bidirectional, zero visible leakage |
| Shell Test | 1.5 times rated pressure, water, per EN 12266-1 / API 598 |
| Operation | Quarter-turn, clockwise to close |
| Component | Material | Standard |
|---|---|---|
| Body | Ductile Iron / WCB / CF8 / CF8M | ASTM A536 / A216 / A351 |
| Disc | Ductile Iron, epoxy or nylon coated, optional CF8M | ASTM A536 / A351 |
| Seat | EPDM / NBR / FKM / PTFE | EN 681-1 / ASTM D2000 |
| Metal Backup Ring | SS316 / steel with corrosion-resistant coating | ASTM A276 |
| Shaft | SS416 / SS431 / SS316 / 17-4PH | ASTM A276 / A564 |
| Bearing | PTFE-lined DU bushing / bronze | — |
| Internal Fasteners | SS316 | ASTM A276 |
| Seat Material | Typical Temperature Range | Recommended Service |
|---|---|---|
| EPDM | -10°C to +120°C | Water, wastewater, dilute acids, ozone, and potable water service |
| NBR | -10°C to +80°C | Water with oils, hydrocarbons, and general industrial fluids |
| FKM | -15°C to +200°C | High-temperature oils, chemicals, and solvents |
| PTFE | -25°C to +180°C | Strong acids, alkalis, solvents, and high-purity process media |
The double‑shaft disc adopts independent upper and lower shaft segments to support the disc from both ends. This structure optimizes radial alignment and minimizes disc deflection under differential pressure. For small‑bore butterfly valves in particular, the double‑shaft layout enables a larger effective flow area, permitting higher media flow capacity compared with single‑shaft alternatives. Besides, this design facilitates easier on‑site installation and removal of the disc during maintenance, and guarantees stable seat contact across the full closing stroke.
| Industry | Application |
|---|---|
| Municipal Water | Pump station isolation, distribution main isolation, treatment plant utility lines |
| Wastewater | Influent and effluent lines, sludge transfer, chemical feed isolation |
| HVAC | Chilled water, condenser water, and cooling tower isolation |
| Chemical Processing | Corrosive utility lines, process isolation, and skid-mounted equipment |
| Fire Protection | Fire pump suction and discharge isolation, sprinkler mains |
| Marine | Ballast, cooling water, and auxiliary systems |
The DN200 valve is supplied with an ISO 5211 top flange for direct actuator mounting. Available operator configurations include:
Factory-mounted operator assemblies are stroke-tested before shipment. Limit switches, positioners, and declutchable manual overrides are available as options.
Each valve receives the following standard inspection and test operations:
Material test certificates per EN 10204 3.1, PMI, and third-party witnessed testing are available on request.
The metal backup ring provides positive radial support for the seat cartridge, prevents seat extrusion under differential pressure, and holds the seat in position during pressure reversals or vacuum conditions.
A double-shaft disc uses separate upper and lower shaft sections to support the disc at both ends. This improves disc alignment, reduces deflection, and helps maintain consistent seat contact throughout the operating stroke.
Yes. The lugged body allows each pipe flange to be bolted independently. With a blind flange on the downstream side, the valve can be used for end-of-line service at its rated pressure.
Yes. The ISO 5211 top flange supports manual lever, gear operator, pneumatic actuator, and electric actuator configurations. Factory-mounted and stroke-tested actuator assemblies are available.
From raw material inspection to final delivery, every butterfly valve undergoes a comprehensive quality inspection to ensure reliable performance and compliance with international standards.
