Power Generation Valve Solutions — Steam, Feedwater & Cooling Water

Start with the valve datasheet, P&ID, line list or valve schedule if available. Also provide the medium, design and operating pressure-temperature conditions, line size, pressure class, end connection, required quantity and applicable standard. For regulation duties, include minimum, normal and maximum flow plus inlet and outlet conditions. For actuated valves, include the power supply, control signal, fail position and required documents.

It depends on the required operating range. Startup flow can be much lower than full-load flow, so a valve selected only for maximum capacity may spend too much time near a low opening, while a valve sized only for low flow may restrict full-load operation. Submit the minimum, normal and maximum flow cases together with inlet and outlet pressure-temperature conditions for configuration review.

In a high-pressure liquid pressure-reduction duty, local pressure inside the valve can fall below the liquid vapour pressure. Vapour bubbles then form and collapse as pressure recovers downstream, which can create noise, vibration and damage to internal surfaces. If vapour remains after the valve, the duty is flashing rather than cavitation. The inlet and outlet conditions, temperature, flow range and pressure drop are therefore essential selection inputs.

Boiler-water blowdown reduces pressure across the valve and may create flashing. The water can also contain elevated total dissolved solids and suspended matter. Combined with repeated operation, these conditions can increase velocity, erosion and wear at seats and internal flow paths. State whether the valve is for continuous or intermittent blowdown, together with the pressure-temperature conditions and available water-chemistry information.

No. Pressure class is only one part of the review. Main-steam suitability also depends on the confirmed design temperature, material requirements at temperature, thermal cycling, end connection, shut-off duty, leakage requirement and the applicable project specification. Quote the complete pressure-temperature service condition rather than pressure class alone.

Do not select by nominal size alone. A pump trip can cause rapid flow reversal, and the valve response depends on the pump duty point, system curve, line velocity, pipe arrangement, installation orientation and medium condition. Provide the pump type, operating flow, working pressure, trip scenario and available installation information when requesting a check-valve review.

Identify the water source and provide available chemistry information, including chlorides where relevant, suspended solids, treatment chemicals and operating temperature. Fresh water, brackish water, seawater and reclaimed water can create different corrosion and fouling considerations. Also confirm the line size, operating pressure, isolation or control duty, and the required leakage level.

Confirm the required datasheet, drawing approval process, material information, inspection and test requirements, marking, packing and document scope before the order is released. For actuated valves, agree the actuator type, power supply, control signal, duty cycle, fail position, manual override and any site-specific electrical or hazardous-area requirements that apply to the project.