Gate Valve - Conventional Power Plant | Neway

Neway Gate Valve for Conventional Power Stations

The Neway Conventional Power Plant Gate Valve serves as an isolation valve for primary and auxiliary lines in power generation facilities, particularly for high-pressure steam, superheated steam, feedwater, boiler drain/vent, and thermally stressed circuits. It is designed for fully open or fully closed positions and is not intended for throttling.

Operational Scope

• Sizes: 2"–30" / DN50–DN750
• Pressure rating: ASME Class 900–4500 / PN150–PN760
• Ends: butt weld
• Body materials: carbon steel, stainless steel, alloy steel
• Operation: handwheel, gearbox, pneumatic, hydraulic, or electric actuator

Construction and Materials

The standard version is a high pressure flexible wedge gate valve with a single wedge and pressure seal bonnet. Available materials include WCB, WC6, WC9, C12A, CF3M, CF8M, and forged/alloy materials like A105, F11, F22, F91, F92, F304/F316, and stabilized stainless grades F321/F347.

Applications in Power Plants

Typical installation points:

• main steam and hot reheat lines
• boiler feedwater and economizer isolation
• superheater/reheater drains and vents
• bypass or warm-up lines
• condensate and high-pressure auxiliary systems

For large diameters or high ΔP, consider bypass balancing to reduce opening torque and thermal shock. The brochure mentions bypass for upstream/downstream pressure balancing and reheating piping.

Selection vs. Parallel Slide

The flexible wedge gate valve is used as a general high-pressure isolation valve. For applications with severe thermal cycles or risk of thermal binding, consider a parallel slide gate valve, which in the same Neway program covers Class 300–4500 and uses a different seating logic.

FAQ

Why butt weld?
In main steam and feedwater lines, it reduces potential external leakage points compared to flanged connections.

Is an actuator needed?
For large DN, high ΔP, or remote operation. Torque, stem travel, operation time, and limit switches are controlled.

What is checked during maintenance?
Stem packing, backseat, seat leakage, bypass operation, and thermal stress after start-up/shutdown cycles.