Viti Fluid Control: With precision valve technology, it helps thermal power plants carry out energy-saving renovations of the "three reforms in linkage"

W&T Fluid Control, relying on Germany's century-old valve technology accumulation and global service experience in the thermal power industry, is deeply involved in the technological transformation and upgrading of key process valves in thermal power plants. It provides high-performance, long-life, and highly reliable fluid control solutions for boilers, steam turbines, and auxiliary systems, helping power plants reduce coal consumption, enhance peak shaving capacity, and ensure safe operation.

I. Boiler side valve Renovation: Comprehensive upgrade from fixed row continuous row to desuperheating water system

The boiler side is the area with the highest concentration of high-temperature and high-pressure valves in thermal power plants and is also the focus of energy-saving renovations. Vitet has provided mature technical solutions for the following key workstations:

The fixed blowdown (bottom blowdown) and continuous blowdown (surface blowdown) conditions of boilers in regular blowdown and continuous blowdown systems are characterized by complex media, large pressure differences, and gas-liquid two-phase flow. Valves are prone to erosion and cavitation damage.

    Viti solution: The labyrinth sleeve drain valve with a multi-stage pressure reduction structure decomposes the high pressure difference into multiple stages of pressure reduction, effectively eliminating flash evaporation and cavitation. The sealing surface is surfacing with cobalt-based hard alloy, significantly enhancing the service life.

2. Desuperheating water regulating valve (superheater/reheater) The desuperheating water regulating valve is a key position in the boiler thermal system. Common failure modes include unstable regulation, internal leakage, erosion damage, etc., which directly affect the control accuracy of the main steam temperature.

    Viti Solution: We offer a labyrinth multi-stage pressure reducing regulating valve specially designed for desuperheating conditions. It features excellent cavitation resistance and stable regulating characteristics, and is compatible with superheater and reheater desuperheating systems. It has been successfully applied in multiple supercritical and ultra-supercritical units.

3. Boiler steam soot blowing regulating valve

The soot blowing system has high steam parameters and frequent opening and closing. The valves are constantly eroded by steam flow, which can easily lead to problems such as damage to the sealing surface and internal leakage.

    Viti solution: It adopts a hard alloy surfacing sealing surface and an erosion-resistant flow channel design to ensure the long-term reliable operation of the valve under high-frequency opening and closing conditions.

4. Boiler PCV Valve (Pressure Relief Valve) The PCV valve is used for overpressure protection in superheater and reheater systems, and it is required to open quickly and seal reliably.

    Viti Solution: We offer high-capacity and high-pressure PCV valves with sensitive action and reliable sealing to ensure the safe operation of boilers.

5. 360/361 valves (Circulation pump flow Regulating Valve/Water Level regulating Valve for Water Storage Tank) The 360 valve regulates the outlet flow of the circulation pump, while the 361 valve controls the water level in the water storage tank. Both are key regulating devices for boiler startup and low-load operation.

    Viti solution: It adopts a multi-stage pressure-reducing structure that is resistant to erosion and cavitation, combined with a high-precision electric actuator, to achieve precise regulation and long-term stable operation.

6. Boiler air vent valve: The boiler air vent valve discharges excess pressure during the boiler's start-up and shutdown conditions. The working conditions are harsh, involving steam-water mixtures and high-temperature and high-pressure steam.

    Viti Solution: We offer dedicated exhaust valves that are resistant to erosion and have reliable sealing, reducing the frequent tripping of safety valves and ensuring system stability.

7. Main feed water (bypass) regulating valve and feed water System Optimization Under the trend of wide-load denitrification transformation, the optimization of the feed water system has received attention. By moving the feed water bypass regulating valve from the boiler end to the feed water pump outlet, the flow resistance and valve torque can be reduced, and energy loss can be decreased.

    Viti solution: Equipped with high-precision water supply regulating valves and bypass valves, it supports system optimization layout and enhances the operational efficiency of the full-load section.

Ii. Turbine Side Valve Renovation: The Upgrading Path of Steam Traps and Minimum Flow Valves

There are numerous valves on the steam turbine side, among which steam traps, minimum flow valves for feed water pumps, and high-load emergency steam trap regulating valves are key equipment that affect the economic efficiency of the unit. Data shows that when the leakage of high-quality steam valves reaches 1% of the main steam flow, the coal consumption for power supply may increase by 2.8 to 3.14g/(kW·h).

1. Main steam trap: The steam trap is one of the valves with the largest number and the harshest working conditions in thermal power plants. Approximately 80 sets of 300MW units and about 150 sets of 1000MW units are configured. With the improvement of the flexibility of the unit and the frequent start and stop, the frequency and pressure difference that the steam trap bears have increased sharply, making it a major area for internal leakage.

    Viti Solution: Y-type steam Trap: Inclined valve stem + Y-shaped flow channel design, low flow resistance, combined with the fully guided piston valve disc in the middle cavity of the valve body, effectively avoids jamming and vibration

Pressure reducing protection device (patent) : When opened, the medium is first blocked and decelerated, and then further decelerated through the countercurrent of the hole, avoiding direct erosion of the sealing surface and doubling the service life. Manual door + automatic door combination configuration is provided. When the automatic door has internal leakage, it can be urgently isolated to ensure safety

2. Minimum flow valve for feed water pump: This valve opens for recirculation when the feed water pump is under low load to prevent cavitation of the pump. It is one of the valves with the highest failure rate in power plants due to its large pressure difference and severe erosion.

    Viti solution: Labyrinth sleeve multi-stage pressure reduction structure, gradually reducing pressure, effectively eliminating high-flow erosion and cavitation damage. The sealing surface is made of hard alloy overlay welding, with a service life far exceeding that of ordinary labyrinth valves. It has successfully replaced imported products in the recycling systems of many domestic power plants.

3. Gaojia Emergency Steam Trap Regulating Valve: When a fault occurs, the Gaojia emergency steam trap quickly drains water to protect the Gaojia system. Units of 300MW and below can be retrofitted with two-position quick-opening and quick-closing valves.

    Vitel Solution: We offer quick-opening and quick-closing steam traps with rapid response, reliable sealing, and compatibility with various high-protection logics.

    Iii. Heating Renovation and Flexibility Renovation

Vitite's key valve support: 1. Cylinder cutting modification (near-zero output of low-pressure cylinder) - connecting pipe butterfly valve

In the cylinder cutting modification, the steam intake of the low-pressure cylinder is precisely controlled through the butterfly valve of the connecting pipe. This valve is required to have comprehensive performance such as regulating function, quick-closing function and zero-leakage seal, and is one of the core equipment for cylinder cutting transformation.

    Viti Solution: We offer large-diameter three-offset metal hard seal hydraulic/electro-hydraulic linkage butterfly valves (DN1400 and above), featuring the following:

Triple eccentric metal hard seal: Zero leakage, bidirectional pressure resistance

Dual functions of regulation and quick shutdown: Precisely adjust the steam intake flow during normal operation, and quickly shut down to protect the steam turbine in case of fault

Anti-erosion design: The metal hard sealing ring is circularly symmetrical, effectively resisting steam erosion. The heating jacket is optional: suitable for low-temperature environments

This type of valve has been verified in the LV valve (hydraulic butterfly valve) project of Datang Harbin No.1 Thermal Power Plant. Due to its irreplaceability, the power plant adopted a direct procurement method to replace it with the original brand.

2. Layout of industrial heating valves

Steam is extracted from different positions such as main steam, cold recirculation, and hot recirculation for industrial heating, involving desuperheating and pressure reducing devices as well as matching regulating valves, shut-off valves, safety valves, etc.

    Viti Solution: We offer complete valve solutions for various heating routes such as direct supply of main steam with reduced temperature and pressure, cold re-extraction, and hot re-extraction, which are compatible with all kinds of steam parameters.

3. Molten salt energy storage and wide-load denitrification - Bypass flue/feed water bypass

In deep peak shaving scenarios, wide-load denitrification technologies (such as flue gas bypass, economizer feed water bypass, staged layout, elastic reheating, etc.) require a large number of regulating valves, shut-off valves and bypass valves.

    Viti Solution: It provides flue gas bypass baffle doors, feed water bypass regulating valves, economizer recirculation system valves, etc., to support the unit in meeting environmental protection emission requirements within the full load range.

Iv. Technical Accumulation and Project Practice of Viti

Conclusion: With valves as the fulcrum, unlock new space for energy conservation in thermal power

The "Three Reforms in Tandem" is not merely a simple equipment replacement, but a technological upgrade based on system optimization. Viti adheres to German precision engineering technology as its foundation and is oriented towards the demands of harsh working conditions. It continuously delves into the boiler side, turbine side, heating and flexibility transformation, using high-performance valve products to assist thermal power plants in reducing coal consumption, enhancing peak shaving capacity and ensuring safe operation.

Vitet - Providing more reliable, longer-lasting and more efficient fluid control solutions for the "three reforms in uncoordinated" of thermal power.