Detailed Product Description

Y43H  steam pressure-reducing valve

Application and main characters

This series of pilot piston-type pressure reducing, is consist of main valve and pilot valve. Main valve is composed of seat, main disc, piston, cylinder, spring and other parts. Pilot valve mainly include seat, disc, diaphragm, spring, adjusting spring etc. By regulating the pressure of adjusting spring, to set the outlet pressure. Adopting diaphragm sensing the changes of outlet pressure, through pilot valve driving piston to regulate the flow area for throttling section of main valve, to attaining the goal of pressure reducing and retaining.

Y43H is suitable for pipeline with steam medium , Y43F is suitable for pipeline with oxygen medium. By adjusting, inlet pressure will be lowered to a certain needed outlet pressure. When the inlet pressure and flow change, the outlet pressure can be kept within a range by medium energy itself, but the difference between inlet pressure and outlet pressure must be ≥ 0.2 Mpa/cm² .

Working principle and structure

When the pressure reducing valve out of factory, adjusting spring is un-compressed, the main disc and deputy disc are closed.

When using, rotating the adjusting bolt, compressing the adjusting spring, then the diaphragm moves downward to open the deputy disc. Through A hole and deputy seat, the medium enters B hole and onto piston . Under the function of medium, piston moves downward to push main disc out of main seat, enabling medium flows valve back, and enters diaphragm bottom through C hole.

When the downstream pressure exceeds adjusted pressure, pushing diaphragm upward to compress the adjusting spring. Then deputy disc moves towards the closing direction, lowered the medium that enters onto piston, the pressure will also lower accordingly. At this time, under the push from spring force of main disc , the main disc moves upward. Reducing the gap between main disc and main seat, the medium flow will reduce accordingly. Then the downstream pressure lowered to new balance.

On the contrary, when the downstream pressure is lower than adjusted pressure, the gap between main disc and main seat becomes larger, the medium flow will increase accordingly, enabling the downstream pressure rising to a new balance.