Pressure reducing valves are designed for use in steam systems, regulation according to the principle "after itself". Used for high steam flow rates and precise pressure maintenance.

In pilot operated pressure reducing valves, the opening and closing of the control pilot valve is controlled by the balance of force between the control spring and the secondary pressure, in the same way as in direct acting pressure reducing valves. The difference is that the control pilot valve regulates the pressure above the piston only, while the lower plane of the piston is affected by the steam flow with secondary pressure. The piston is directly connected to the main valve, which regulates the main steam flow. This increases the effort required to open the main valve, allowing for a larger valve size and greater capacity with lower displacement pressure. Through the use of a piston, a small change on the control pilot is enough to control the flow of steam through the main valve. And the increased piston stroke and its surface area make it possible to control the main valve with a much larger cross section and throughput.

Instantaneous response and tight control of adjustable pressure over a wide range of steam flow rates are the main distinguishing features of pilot operated pressure reducing valves compared to direct acting gearboxes.

The gearbox is sensitive to poor quality steam containing dirt, scale, condensate. For reliable operation, it is necessary to install a filter, separator or condensate pocket.

Pressure setting range: