Customized High-precision Control Performance Steam Turbine Pilot Valve Spool with Superior Sealing & High-strength Wear-resistant Construction

The pilot valve spool is a core control element of the steam‑turbine governing system. It receives control signals from the governor or electro‑hydraulic converter. Axial displacement of the spool changes the flow area of oil ports to regulate the flow rate and pressure of control oil, so as to drive the servo‑motor and realize precise adjustment of turbine steam‑inlet volume.

As a vital link between control signals and actuators, sensitivity, stability and reliability of the pilot valve spool directly determine turbine speed‑governing accuracy, load‑regulation performance and operational safety.

• High‑precision Control Performance: Precision‑ground matching structure is adopted for spool and sleeve, with fitting clearance controlled within 0.005‑0.01 mm. It ensures rapid response to control signals with displacement sensitivity up to 0.01 mm grade, meeting high‑precision speed‑regulation requirements of steam turbines.
• Superior Sealing & Anti‑interference Performance: Multiple sealing oil chambers and oil‑return passages are configured to effectively prevent internal oil leakage and cross‑chamber oil overflow. It minimizes disturbance from external oil‑pressure fluctuation and guarantees stable control under various operating conditions.
• High‑strength Wear‑resistant Construction: Spool and sleeve are made of high‑strength alloy steel (e.g. 20CrNiMo, 12Cr1MoV) with surface hardening treatment (hardness HRC55‑60). Excellent wear resistance and anti‑sticking capability enable long‑term high‑frequency regulating operation.
• Optimized Oil‑flow Design: Streamlined internal oil passages reduce flow resistance and eddy‑current loss, lower pressure fluctuation during regulation and improve utilization efficiency of control oil.