The main purpose

Extraction quick-closing check valve is a special valve used in the extraction system pipeline of thermal power plants. It is used to prevent the pressure in the steam turbine from suddenly reducing when the steam turbine component suddenly sheds load, causing the steam in the extraction pipe and each heater to flow back into the steam turbine, causing The steam turbine blades are broken, causing serious accidents that damage the turbine generator, and prevent the leakage of the heater system pipeline from water entering the steam turbine from the extraction pipeline to cause a water hammer accident, so as to protect the safe operation of the steam turbine. The extraction check valve can close quickly and tightly within 0.5 seconds to ensure that when the water level in the feed water heater is extremely high, the pneumatic device components will quickly isolate the steam turbine after receiving the liquid backflow signal to protect the steam turbine and steam extraction system.

Features

• The valve adopts a swing structure, the cast valve body adopts a streamlined valve body design, and the valve has small flow resistance;

• The sealing surface of the valve body is tilted 30° to reduce the closing time of the check valve and ensure quick closing;

• The valve disc of the closing piece is movably connected to the valve stem through the rocker. The valve disc rotates around the valve stem, which can make the valve disc accurately land on the sealing surface of the valve body to ensure that the sealing surface matches;

• When the diameter of this series of check valves is large, a weight can be designed according to user requirements to balance the gravity moment of the valve disc assembly. When the medium flows forward, it helps to open the check valve and keeps the check valve stable and reduces vibration during operation;

• The side-mounted actuator is a spring-return single-acting linear stroke pneumatic device or a hydraulic device. The pneumatic/hydraulic device is installed on the left side by default (viewed in the direction of air flow). If the user has special requirements, which must be stated in the contract, the pneumatic/hydraulic device can be installed on the right side.

Main design specifications