The A51H single-lever safety valve is a direct-acting safety valve utilizing the lever-and-weight principle. It amplifies the force of the weight through a single-lever system and transfers it to the valve disc to provide sealing force. When the system pressure acting on the force below the valve disc exceeds the mechanical force set by the lever and weight, the valve disc is lifted, allowing the medium to be released; after the pressure decreases, the weight force resets the valve disc to close. The "H" represents that the sealing surface is made of alloy steel. This valve has a simple and intuitive structure, with stable set pressure (determined by the position of the weight). It is a classic and reliable safety relief device used in traditional industrial fields for medium and low pressure, large displacement conditions. It was widely used in early industrial boilers, small power stations, low-pressure pressure vessels, compressed air storage tanks, and certain stationary steam power equipment. In modern industry, due to its large size, sensitivity to vibration, and relatively cumbersome adjustment of set pressure, it has been largely replaced by spring-loaded safety valves. However, it is still used in some specific traditional equipment or in applications with special requirements for explosion protection and maintenance-free.A51H Single-Lever Safety Valve Product Diagram

The GA44H double-lever safety valve is a heavy-hammer safety valve featuring a double-lever series amplification mechanism and alloy steel sealing. It amplifies the force of the heavy hammer twice through a two-stage lever system, thereby achieving greater sealing force with a smaller hammer or setting for higher pressure. When the system pressure exceeds the mechanical force set by the lever ratio and the position of the heavy hammer, the valve disc is lifted to relieve pressure; after the pressure recovers, it closes under the action of the heavy hammer. The "H" represents that the sealing surface is made of alloy steel material. This design maintains the advantages of stability and reliability of lever valves while expanding their pressure application range. It is a classic mechanical safety device used in traditional industries for medium and high pressure, large displacement conditions. It was widely used in early medium and high pressure power station boilers, industrial power boilers, large pressure vessels, and marine steam systems. In modern times, due to its complex structure, large size, and relatively inconvenient adjustment, it has been largely replaced by high-performance spring-loaded safety valves and pilot-operated safety valves. Currently, it is mainly used for maintenance and replacement of specific traditional equipment, or in some special industrial applications where such specifications are still required.GA44H Double-Lever Safety Valve Product Diagram

The AH42F safety reflux valve is a composite valve that integrates safety relief and medium reflux functions. It is typically installed at the outlet of a pump or on pipelines requiring pressure protection. When the pipeline pressure exceeds the set safety value, the valve opens as a safety valve to relieve pressure. When the pump suddenly stops or the downstream pressure is higher than the upstream pressure, the valve can act as a check valve to allow limited reflux of the medium, preventing water hammer, system backflow, and pump reversal. The "F" in the valve model indicates that the valve seat sealing surface is directly machined from the valve body material. This valve simplifies pipeline design and provides integrated safety protection and hydraulic control for pumps and pressure systems. It is mainly installed in the outlet pipelines of centrifugal pumps, water supply systems, fire pump sets, irrigation systems, and industrial circulating water systems. It is used to prevent system overpressure, avoid the hazards of water hammer during pump shutdown, and prevent damage to the pump caused by medium backflow. It is a commonly used multifunctional protection valve in pump pipelines.GA42Y Single Lever Safety Valve Product Diagram