1. Applicable Standards and Regulatory Basis
Our DIN Marine Quick Closing Valves are designed, manufactured, and certified in strict conformity with:

• SOLAS Chapter II-2, Regulation 4.2.2: Mandates remote-operated quick closing valves on fuel oil, lubricating oil, and other flammable oil tank outlets in machinery spaces, with fail-safe closure capability.

• DIN 86251: Ships and marine technology — Quick-closing valves for nominal diameters DN 15 to DN 200 and nominal pressures PN 6 to PN 40. This is the primary standard defining design, materials, fire resistance, and type-testing procedures.

• DIN EN 1092-1: Flanges and their joints — circular flanges for pipes, valves, fittings and accessories, PN designated.

• DIN EN 12266-1: Industrial valves — testing of metallic valves, governing shell and seat tightness tests.

• DIN EN 1563 / 10213 / 10222: Material standards for ductile iron, steel castings, and forgings used in valve bodies, bonnets, and pressure-retaining parts.

• IACS UR (Unified Requirements): Harmonized international requirements for quick closing valve design, fire resistance, and remote actuation system integrity.

2. Design Configuration and Actuation Methods
The valve assembly consists of a main body (globe, angle, or straight pattern), a disc and seat mechanism, and a remote actuation system. We offer the following actuation methods, all fully compliant with DIN 86251:

• Pneumatic Actuation (Air-to-Open, Spring-to-Close, Fail-Safe): The most common arrangement. Control air pressure acts on a piston to compress a powerful spring and hold the valve open. In an emergency, the air is vented remotely via a push-button or solenoid valve, and the spring instantly forces the valve closed. Closure is guaranteed even upon total loss of ship’s air supply.

• Hydraulic Actuation: Hydraulic oil pressure holds the valve open against the spring. Releasing pressure causes immediate spring-driven closure. Used where a dedicated hydraulic safety circuit is installed.

• Mechanical Cable / Wire-Pull Actuation: A wire rope and pulley system connected to a latched, spring-loaded or deadweight lever. Pulling a handle at the remote station releases the latch, and the valve slams shut. Operates entirely independently of all ship power and control systems.

• Manual Override: A local handwheel is always provided for manual closure and controlled reopening during testing and maintenance, with the actuator mechanism automatically disengaged.

3. Material Selection to DIN/EN Standards
Materials are selected for maximum reliability and long service life in the aggressive engine room environment:

• Body & Bonnet: Ductile iron EN-GJS-400-15 (EN 1563), cast steel GP240GH (1.0619) or G20Mn5 (EN 10213), or stainless steel GX5CrNiMo19-11-2 (1.4408, CF8M equivalent). Ferrous bodies receive a heavy-duty, two-component marine epoxy coating.

• Trim (Disc & Seat): Renewable and lapped stainless steel (1.4021, 1.4404) or Monel seating surfaces for positive metal-to-metal shutoff. For clean oil services, soft-seat inserts of PTFE or reinforced FKM provide bubble-tight, zero-leakage closure.

• Stem & Actuator Spring: Stainless steel stem with a high-cycle, corrosion-protected actuator spring (epoxy-coated alloy steel or stainless spring steel).

• Fire-Safe Packing & Gaskets: Graphite stem packing and spiral-wound stainless steel/graphite bonnet gaskets, maintaining leak-tightness even under fire exposure per DIN 86251 and SOLAS requirements.

4. Key Technical Features and Safety Benefits

• Fail-Safe Spring Closure: The actuator spring constantly drives the valve towards the closed position. Any loss of actuating pressure or cable tension results in automatic, instant valve closure — no external power or operator action required.

• Remote Emergency Shutoff: The valve can be triggered from multiple safe locations such as the engine control room, fire control station, or escape routes, eliminating the need to enter a burning machinery space.

• Rapid, Positive Fuel Isolation: The powerful spring generates high closing force, cutting through viscous fuel and overcoming disc stiction to achieve a tight seal at full system pressure in well under five seconds.

• Direct DIN Flange Integration: Body flanges are drilled precisely to EN 1092-1 PN6, PN10, PN16, PN25, or PN40 patterns, ensuring a perfect, gasket-free fit with existing metric piping without adaptor pieces.

• Clear Position Indication and Feedback: A prominent mechanical indicator shows OPEN/CLOSED status on the actuator. Limit switch boxes can be factory-fitted to provide remote electrical signals to the vessel’s control and monitoring system.

• Low Maintenance, Robust Design: The simple piston-and-spring actuator has minimal moving parts and is built to withstand continuous vibration, elevated ambient temperatures, and the oily, salt-laden atmosphere of ship machinery spaces.

5. Typical Marine Applications

• Fuel Oil System: Outlets from heavy fuel oil (HFO) and marine diesel oil (MDO) storage tanks, settling tanks, and service tanks.

• Lubricating Oil System: Main engine and auxiliary engine sump tank outlets, cylinder oil storage tanks, and LO purifier supply lines.

• Thermal Oil / Hot Oil Systems: Isolation of heater and expansion tank connections.

• Hydraulic Oil Tanks: Remote shutoff for hydraulic power pack reservoirs.

• Other Flammable Fluids: Any application where SOLAS and classification society rules require remote, fail-safe fuel isolation.