Steam pressure reducing valves are used to stabilize steam pressure entering control valves, flow meters, or directly into the equipment. Choosing the right type of steam pressure reducing valve is crucial.
For applications with low flow equipment and facilities where pressure control requirements are not stringent, a direct-acting pressure-reducing valve is recommended. For medium to low flow equipment, facilities, and pipeline systems, a pilot-piston type pressure-reducing valve is available. For high flow, stable pressure control equipment, facilities, and pipeline systems, a pilot-diaphragm type pressure-reducing valve can be selected.
1. The pipe diameters for upstream and downstream pipelines should be selected correctly based on flow rate and pressure.
2. The pressure relief valve should not be oversized, as it may cause cavitation and lead to "oscillation" in downstream pressure.
When the pressure reduction ratio exceeds 10:1, it is recommended to use a series installation of pressure reducing valve sets. When there are variations in flow rates for the pressure reducing valves, and the flow ratio is greater than 10:1, it is suggested to use a parallel installation of pressure reducing valve sets.
4. Selecting the right valve ensures minimal wear and precise pressure control.
5. Although the reliability and accuracy of steam pressure reducing valves depend on the correct selection, proper installation is equally crucial.
6. Pressure reducing valves should be protected from pipe debris and moisture; a water-air separator and a 100 mesh filter must be installed.
The feedback sensor tube of the pressure relief valve must be properly installed and should have a certain angle and distance (not too close to the outlet of the pressure relief valve).
All upstream and downstream pipelines, as well as other accessories, must be properly selected. The correct size of the shut-off valve should match that of the upstream and downstream pipelines. If the downstream pipeline or connected equipment cannot withstand the maximum pressure generated by the upstream steam, a safety valve must be installed downstream. The valve should be set at a pressure equal to or below the maximum allowable working pressure of the downstream equipment, but should have sufficient margin above its normal operating pressure. The discharge capacity of the safety valve must be greater than the steam flow rate when the pressure-reducing valve is fully open at the maximum possible pressure upstream.
