The A43Y spring-loaded full-opening dual safety valve is a hard alloy-sealed full-opening safety valve designed with a dual-valve parallel redundancy configuration. It integrates two independent spring-loaded full-opening safety valves into a shared valve body or manifold, and is equipped with a switching mechanism. When the primary safety valve requires offline calibration, maintenance, or malfunctions, the standby safety valve can be activated through switching operations, ensuring uninterrupted overpressure protection for the protected system. It is specifically designed for demanding industrial processes that require absolute continuous safety protection without any interruptions. It is dedicated to critical industrial devices where safety protection must not be interrupted, such as the main steam system of large thermal power plants, auxiliary systems of nuclear power plants, core reactors and hydrogenation units in petrochemical industries, continuous production lines for synthetic ammonia/ethylene, and process systems on offshore oil platforms. It is the ultimate solution for situations where standby safety valves are mandated by laws and regulations or process requirements.

A43Y Spring-Operated Full-Lift Duplex Safety Valve Product Diagram

1. Dual-valve redundancy involves the parallel connection of two independent full-opening safety valves that can be switched online, forming a redundant system where "one is in use and the other is standby". Through mechanisms such as three-way switching valves, the main path can be safely switched to the standby path under system pressure, enabling online testing and maintenance of the valves and ensuring zero interruption of protection functions.

2. The sealing surfaces of the hard alloy sealing ("Y"-type) valve disc and valve seat are both surfaced with high-hardness alloys such as Stellite, which exhibit excellent wear resistance, high temperature resistance, corrosion resistance, and erosion resistance, ensuring long-term sealing reliability under harsh media and frequent operation.

3. The spring-loaded full-opening type with large discharge capacity adopts a full-opening structure. When the pressure exceeds the set value, the valve disc quickly opens fully, providing a large discharge area and strong discharge capacity (displacement), meeting the needs of systems such as steam and gas for rapid and large-scale pressure relief.

4. Integrated design and compact structure: The two valve bodies, inlet and outlet channels, and switching mechanism are highly integrated, significantly saving installation space and pipeline layout costs compared to installing two separate valves, and enhancing the overall reliability of the system.

5. The overall structure, featuring high pressure, high temperature, and high reliability, is designed for enhanced performance under high pressure (PN16-PN100) and high temperature (≤450℃) conditions. The dual-valve redundancy mechanism fundamentally eliminates single point failures, providing the highest level of safety for critical devices.

A42Y Spring-Operated Full-Lift Safety Valve Structural Diagram

Part Name Material

Performance Specifications Table

A42Y Spring-Operated Full-Lift Safety Valve Outline Drawing

Dimension Chart