1. Available Standards and Design Basis
We produce Marine Butterfly Valves in strict accordance with the following international standards, selectable based on your vessel’s specifications:

• DIN/EN Standard: Designed to DIN 86059, EN 593, with PN10/PN16 flanges per EN 1092-1. Face-to-face per EN 558 Series 20.

• JIS Standard: Designed to JIS F7480, with 5K/10K/16K flanges per JIS B2220/JIS B2239.

• GB Standard: Designed to GB/T 3036, with PN6/PN10/PN16 flanges per GB/T 2501.

• ANSI/ASME Standard: Designed to API 609, with Class 150/300 flanges per ASME B16.5 and face-to-face per API 609/MSS SP-67.

• Common Testing Basis: All valves are tested in accordance with the applicable pressure test standard (EN 12266-1, JIS F7400, GB/T 600, or API 598) to confirm shell integrity and seat tightness.

2. Marine-Grade Material Selection
Materials are specifically chosen to resist the corrosive effects of seawater, humidity, and aggressive fluids:

• Body: Ductile iron (e.g., GJS-400-15, FCD400, QT400-18, or ASTM A536) with high-build two-component epoxy coating, or stainless steel (CF8M/316) for direct seawater contact. Wafer, lug, or double-flanged configurations are available.

• Disc: Bronze, duplex stainless steel, or 316 stainless steel, selected for pitting and crevice corrosion resistance.

• Seat/Liner: Vulcanized EPDM (standard for seawater, freshwater), NBR (for fuel and lube oil), or FKM/NBR (for elevated temperatures and chemicals). The liner extends fully over the flange face, forming a built-in gasket that eliminates the need for additional flange seals.

• Shaft: Stainless steel with an anti-blowout design, rotating on self-lubricating, non-metallic bearings that isolate the shaft from the body and prevent galvanic corrosion.

3. Key Technical Features

• Bidirectional Bubble-Tight Shutoff: The resilient seated design provides zero-leakage sealing in both directions, verified by the relevant seat test standard.

• Compact and Lightweight: Short face-to-face dimensions reduce installation space and weight, critical for crowded engine rooms, pump rooms, and skid-mounted equipment.

• Self-Gasketing Flange Connection: The full-face rubber liner eliminates the need for separate gaskets, ensuring a perfect seal against any standard raised-face or flat-face flange.

• Low Operating Torque: The centric disc design and self-lubricating bearings result in smooth, low-torque operation, reducing manual effort and enabling smaller, cost-effective actuators.

• Actuator-Ready Interface: All valves feature a standardized ISO 5211 top mounting pad, allowing direct mounting of lever handles, worm gearboxes, or pneumatic, electric, and hydraulic actuators. Pre-assembled and tested automated packages are available.

• Low Maintenance Design: The non-metallic shaft bearings are lubricant-free and corrosion-resistant, preventing the valve from seizing even after prolonged inactivity.

4. Typical Marine Applications
Marine Butterfly Valves are installed throughout the vessel in critical and auxiliary systems:

• Main and auxiliary seawater cooling circuits

• Ballast water treatment and management systems

• Bilge, stripping, and fire main lines

• Fuel oil and lubricating oil transfer and storage

• Fresh water generators and potable water systems

• Overboard discharge and tank vent lines

5. Quality Assurance, Testing, and Certification

• Testing: Every valve undergoes a hydraulic shell strength test at 1.5 times the rated pressure and a seat leakage test at 1.1 times the rated pressure, achieving zero visible leakage. Test certificates are supplied with each shipment.

• Material Traceability: Full EN 10204 Type 3.1 (or equivalent) material certificates are provided for all pressure-containing and wetted components, including heat numbers permanently marked on the body.