Background

As a core auxiliary power system for main engine and generator startup, the marine compressed air system operates round-the-clock to safeguard vessel navigation and operational safety. With compressed air working across a wide temperature range from -20°C to 200°C, the system features drastic temperature fluctuations and frequent equipment start-stop cycles, imposing stringent requirements on valves in terms of temperature resistance, sealing performance, wear resistance and regulation accuracy.

Conventional common butterfly valves fail to withstand such harsh operating conditions, prone to seal failure under alternating high and low temperatures, leakage caused by abrasion from frequent opening/closing, delayed actuation and short service life. These defects result in compressed air loss and unstable air supply, compromising the startup of power equipment, raising maintenance costs and bringing potential risks to navigation safety. Featuring a triple-eccentric metal hard-seal construction, the GRAT electric flanged hard-seal butterfly valve delivers outstanding wide-range temperature tolerance, superior erosion and wear resistance, consistent sealing performance and fast automated regulation, perfectly matching the operating conditions of marine compressed air systems and enabling safe, stable and efficient operation of onboard auxiliary power systems.

Key Challenges

1. Poor sealing stability under wide temperature variation The compressed air fluctuates between -20°C and 200°C. Conventional valve seals tend to harden, age and deform under alternating hot and cold cycles, reducing the fitting tightness of sealing faces and triggering air leakage and insufficient system supply pressure.
2. Insufficient wear resistance against frequent cyclic operation Frequent startup and shutdown of marine main engines and generators require valves to endure repetitive opening and closing continuously. Traditional valve sealing structures generate excessive friction during actuation; prolonged operation leads to severe seal face abrasion, incomplete shutoff and air leakage, failing to meet the long-term operational demands of marine equipment.
3. Inadequate precision for air supply regulation and shutoff The compressed air system demands rapid medium cut-off and flow adjustment responding to equipment startup/shutdown and working condition shifts. Ordinary valves suffer from slow response speed and poor linear regulation, causing over-supply or insufficient air feed and destabilizing power equipment startup.
4. Poor marine working condition adaptability and inconvenient maintenance Marine piping is installed in compact spaces with persistent mechanical vibration onboard. Many conventional valves feature poorly optimized structures with weak anti-vibration capacity and rely on manual operation incompatible with intelligent marine control systems. In addition, cumbersome disassembly pushes up offshore maintenance expenditure and causes heavy losses from unplanned downtime.

Operating Conditions

Product Name: GRAT Triple-Eccentric Hard-Seal Electric Flanged Butterfly Valve

Application: Marine compressed air systems, installed on air supply pipelines for main engine and generator startup to realize pipeline shutoff and proportional flow regulation

Working Medium: Compressed Air (Operating Temperature: -20°C ~ 200°C)

Nominal Pressure: PN10 / PN16

Nominal Diameter: DN50 ~ DN300 (multiple sizes for various onboard pipe diameters)

Body Material: SUS304 Stainless Steel / WCB Carbon Steel

Sealing Type: Alloy Metal Hard Seal (triple-eccentric metal sealing structure with replaceable metal sealing ring)

End Connection: Flanged Connection

Operation Mode: On-off Shutoff + Proportional Modulating Control

Power Supply: AC220V, AC380V

Product Advantages & Features

Adopting triple-eccentric bevel cutting design, the valve achieves friction-free opening and closing with excellent wear & erosion resistance on sealing faces; the clearance protection design for sealing pairs extends service life remarkably. Compact overall structure with strong anti-vibration performance fits confined installation space and complicated working environments onboard vessels.

Application Performance & Benefits

1. Zero-leakage pressure stabilization under wide-temperature service Alloy hard seal combined with friction-free triple-eccentric structure adapts to -20°C~200°C full temperature spectrum, eliminating seal aging and air leakage to stabilize pipeline air pressure and guarantee reliable startup of marine power machinery.
2. High wear resistance for frequent cyclic operation High-hardness metal hard seal withstands erosion while avoiding contact abrasion between sealing faces during opening/closing, eliminating unexpected air supply interruption and supporting long-term continuous marine operation.
3. High-precision & responsive flow control Electric actuator ensures prompt movement with dual functions of full shutoff and proportional regulation and excellent linearity, enabling rapid adaptation to working condition changes and precise airflow control for smooth equipment startup and shutdown.
4. Superior onboard adaptability & low-cost maintenance Standard flanged connection ensures rigid installation and outstanding vibration resistance to suit compact complex onboard piping layout. Compatible with intelligent automatic control system; replaceable sealing component and easy disassembly effectively cut offshore maintenance expenses and downtime losses.